Afriqiyah Airbus 330 Crash [Archive] - Page 4

Bigpants

20th May 2010, 19:25

Flight 605 was an A320 rather than an A330 but they share very similar automation and fly by wire technology.

Airbus technology is complex and it is vital that one understands what the modes are and what they do. I suspect that the crews training and understanding of the automation will be a key factor in why this aircraft crashed.

Flight 605 was a flight on 14 February 1990 that crashed on its final approach to Bangalore airport, killing 92 people.

The flight, IC-605, took off from Mumbai (Bombay) at 11:58 for a flight to Bangalore. At 12:25 Bangalore approach was contacted and prevailing weather at Bangalore was passed on to the crew. At 12:44, the Airbus A320 was cleared to descend to 11,000 feet and visual approach into runway 9 was cleared.

On final approach, the aircraft descended well below the normal approach profile and kept descending until it struck the boundaries of the Karnataka Golf Club, 2,300 feet (700 m) short and 200 feet (61 m) right of the runway. The aircraft rolled for 80 feet (24 m) and lifted off again for about 230 feet (70 m) and came down again on the 17th green of the golf course.

The landing gear wheels dug into the ground and the aircraft impacted a 12 feet (3.7 m) high embankment, causing the gears and engines to be sheared off. The aircraft continued over the embankment and came to rest in a grassy, marshy and rocky area.

The official verdict of the crash was the "Failure of the pilots to realize the gravity of the situation and respond immediately towards proper action of moving the throttles, even after the radio altitude call-outs of "Four hundred", "Three hundred" and "Two hundred" feet, in spite of knowing that the plane was in idle/open descent mode." [1] However, there were aspersions cast on the then newly launched Airbus A320 and the complications of the aircraft coupled with lack of suitable training for pilots [2].

The well-known industrialist Ashok Vardhan Birla, his wife Sunanda and daughter Sujata were killed in the crash. [3]

Regards Bigpants

White Knight

20th May 2010, 19:45

Jetlag50 - from the A330-200 FCOM 3.01.20 p3

. Wind for takeoff:
Maximum TAILWIND................15 knots

. Wind for landing
Maximum TAILWIND................15 knots

Not quite sure what you're alluding to about 100% flying the approach and landing with a tailwind:rolleyes::rolleyes: It's normal at many airfields due noise abatement - big whoopy deal:E

Besides - it's policy at our company to be fully configured by 1500' and stable by 1000' IMC and 500' VMC. That's a pretty standard deal with most airlines and types these days...

White Knight

20th May 2010, 19:54

Another thing Jetlag - this is a discussion about a 330, not a good 'ole 727 so your comments regarding flap settings are totally irrelevant...

Regarding trim changes at go around - you'll barely notice them manually flying 'cos it's FBW. Basically it will autotrim to give neutral sidestick and maintain 1g at the chosen attitude. Clever heh?

silverstrata

20th May 2010, 21:06

Jetlag:
On 727, you select F25 then F30 or F40 when you are visual. Any large flap retraction on GA would result in serious trim problems.

Selecting three stages of flap, only when visual, on a CAT III approach - now that would make for one wild ride. Yeeehaaa. :ugh::ugh::ugh:

Glad the old generation have retired.... :ok:

mohamed arab

20th May 2010, 21:41

I dont have mutch to say but you should know that libyan pilot are Experienced crews and the expats. only due to short of crew Libyan pilots did not fly for decades during embargo yes and most of them did not get tested, is wrong . and yes we can fly but you must see what happens to the air france a330 are they libyan http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/thumbs.gif we use to fly to a same weather in africa and we never crashed . and if you are apilot which Ithing yes but you are very weak because accidint it can happend to any one most of the crashes happend to amoust experince company so Ithing you took from the dark sid of you personality

SLFinAZ

20th May 2010, 22:26

I'm assuming that a non stable approach would be aborted and a non precision approach would be aborted at the briefed minimum. Under what circumstances would you consider it appropriate to breach minimums and perform such a maneuver vs initiating a go around the moment things were clearly not as expected?

Only thing I can think of is either fuel starvation or loss of power/control authority such that a controlled landing of some kind was the only viable option left.

To me if your less then 100M of the ground and 500M from the threshold and your doing avionic gymnastics something very unexpected (wind shear/equipment failure,etc) happened or you belong in the back of the tube with the rest of us...

RetiredF4

20th May 2010, 23:00

Unfortunaely the thread is running dry, including some turf-wars about how to do this and that in my company versus your habit..........
Some trolls also doing their job pretty good as well and the most expierienced people of PRunNe keeping quiet probably being tired to react to the above mentioned nonsense.

Although i dont feel qualified to do so, i try to summarize a few points which i think are to be considered valuable having read all of the past 777 posts to this event (as retired there is the time for it).

Feel free to ammend and comment (copy and paste would be a method)

* the aircrew was familiar with the field (homebase)
* the flight was cleared for an NPA (NDB, due to VOR being unreliable) Approach to RWY 09
* It could have been flown visual (speculation)
* Weather forecast was VMC bottom line
* however actual weather was worse due to morning fog and rising sun
* No communication wirh ATC is known jet
* There are no confirmed reports concerning technical problems
* Alitalia Flight observed AC with nose down prior or at impact
* Aircraft desintegrated after contact with ground completely
* The ground is hard surface covered with some sand and gravel
* Destruction of Hull shows signs of lot of energy
* Looking at the damage to wheel-assembly the gear was most probably down and was probably sheared of by initial contact with the ground
* There are no visible impact marks from gear or engines
* The tail assembly broke off, HTP and VTP stayed with the tail
* A skin-part of the forward fuselage section is found not far down from the tail
* The wings made it to the end of the debris field
* At least one engine shows signs of higher rpm at time of impact

Thing not yet clear:
* How was the approach flown (auto,.........)?
* What was the reason to descent below MDA?
* Was a goaround initiated and when?
*What could go wrong on an aproach leading to this accident?
* What could go wrong on a goaround leading to this accident?
* What did ATC observe on Radar or Visual?

There might be no answers until data from the recorders are available, so be it, then we wait for them.

And if i overstressed my limits in your sandbox with this post, than shame on me.

franzl

vovachan

20th May 2010, 23:14

For the doubters, check out the pics of the Polish Tu-154 crash in the thread below, which hit upside down. Only the engines, wings and wheels are recognizable, the rest is bits and pieces of trash.

JetLag50

20th May 2010, 23:33

White Knight, those tailwind figures you are playing with, for take off for example: are they with MTOW, what ambient temp, what length runway? Have you ever done performance graphs? Your figures are meaningless twaddle. Hey the B727 can do auto-trim too how about that? But ask too much from it and you could have runaway stabilizer to make your day.

A lot of things could have gone wrong if the guy didnt actually screw up on the GA. He could have applied the power too late and the stick pusher compensated to prevent a wing stall. Could explain Alitalia's guy saying he saw a nose dive. (or does the clever Airbus not do that with all its spatial awareness?). He could have had assymetric flap on retract, compressor stall, fuel blockage (as in BA 777). Look at that Air France that mowed some trees down doing a go around on a demo flight on the A320. Dont know what happened precisely, but that was automation gone mad. So keep an open mind guys.

lomapaseo

20th May 2010, 23:36

For the doubters, check out the pics of the Polish Tu-154 crash in the thread below, which hit upside down. Only the engines, wings and wheels are recognizable, the rest is bits and pieces of trash.

Statements like this provide little conclusive evidence of similarities or dissimalities between accidents.

To make comparisons you must track ground scars vs distance and spread of the debris field in similar open space or heavily treed area.

If significant ground fires were present then destruction from post crash fires might make it even more difficult to compare.

From a resulting debris standpoint after consideration of the impact vector, it's best to look at crushing damage to the hard areas of the aircraft like wing boxes and engines to make finer point assessments.

And of course I suspect that neither of these reference accidents hit upside down, but only ended up having parts tumble after the first impact with trees or ground.

The answer of differences, is in the details which are not resolvable from the photos that we have available to us.

Bluestar51

21st May 2010, 00:30

100PP,

Is it SOP for the Airbus to fly NPAs using a constant rate of descent? Is the NPA flown in MAP mode (not sure about the Airbus term) with the raw data being monitored?

BS

BarbiesBoyfriend

21st May 2010, 01:04

Guys

Whatever happened here was captured by the aircrafts' FDR and CVR.

What do we achieve by guessing?

DutchExpat

21st May 2010, 01:28

I am a little amazed they took untill today to send the flight recorders to France?

RoyHudd

21st May 2010, 07:11

Live, work and fly in Libya (A320) and you won't be amazed. Corrupt and medieval country, although the general population are actually good friendly folk. Not so the dictator's people...the "authorities". They'll have tried to analyse the data themselves, and maybe even cook it.

As for Libyan pilot's abilities. Hard to judge, due to the many years of minimal flying on ancient equipment they have endured. I will however volunteer that the macho culture prevails, and maintenance standards are lamentable.

As already said, this was an accident waiting to happen. Watch this space for the next one. The odd crash doesn't discourage this lot. :\

White Knight

21st May 2010, 07:29

I beg to differ 0-8. The pilot was not flying manually. What sane pilot would fly on idle power at that height if he didnt have confidence in his automation, please explain? He was trying to show the aircraft's ability at automated critical speed and configuration
Quote:
Very low speed, reduced to reach maximum possible angle of attack.
and then hoping to recover with an automated GA. That was the whole purpose of the demo, automated flight at critical speed. OK the trees spoiled his day in the end.

The difference is fairly obvious between the AF 320 - not understanding his automatics (no alpha floor below 100' RA) at an airshow on a CAVOK day and this Afriqiyah 330 obviously descending below minima in poor visibility in direct contravention of all good operating practice and SOP..

Well said Roy Hudd - some folks just have no idea about the MAghreb:=:= and the mentality:ugh:

BOAC

21st May 2010, 07:33

Regarding some recent postings here, may I draw attention to this thread on the mil forum. It contains some good advice.

http://www.pprune.org/military-aircrew/398575-resident-idiot-troll.html

Max Stryker

21st May 2010, 08:26

Ok, now I mostly lurk here, leaving posting to far more experienced guys than myself, and greatly enjoy most of your contributions and insights. However, some of the things said lately have spurred me to actually write this.

"Privilege of a stabilized approach" - I sure hope that JetLag was trolling when he wrote this, because the stabilized approach cannot and never should not be a privilege. It is a requirement. 1000 feet in IMC, and 500 feet in VMC seem to be what most companies prescribe these days. If you are unstabilized at any point below that - go around. No ifs, no buts, no low-level aerobatics - go around. A failure to do so is poor airmanship.

"Twaddle" when speaking of tailwind limitations. How exactly is it twaddle? Twaddle is bringing performance tables into this - it is an operator's limitation, based on the manufacturer's demonstrated wind limitations. If you want to look at the performance tables, you will not limit wind by your TOW, you will limit your TOW by the wind that is blowing down the runway, and thus calculate your max load. Saying that you will not operate with a tailwind is... well, lets just call it - detached from the reality of worldwide day to day operations. There is no contradiction between tailwind and safe operation.

"727 autotrim" While the 727 trims while the autopilot is engaged, it certainly does not have autotrim in the Airbus sense - which operates with the autopilot off. Case in point:
Boeing 727 Stabilizer Trim System (http://www.boeing-727.com/Data/systems/schematic%20stab%20trim%20system.html)

I think I have wasted enough time and reading patience of the people who make this thread, and the rest of pprune, a worthwhile excercise.

rgbrock1

21st May 2010, 13:12

I've noted a couple of references to an Alitalia flight which witnessed the accident aircraft with a nose down attitude. From reading all of these posts it seems that many believe the tail hit first, perhaps breaking off and then the nose down attitude. Which makes sense to this SLF.

It would seem to me, though, that if the Alitalia flight witnessed the nose down attitude and the subsequent crash wouldn't the flight crew also have noticed the lack of a tail and made reference to this as well?

Has anyone seen/read mention of this?

BOAC: Excellent advice on how to deal with the infamous troll.

aterpster

21st May 2010, 14:17

DutchExpat:
I am a little amazed they took untill today to send the flight recorders to France?

It sure got my attention. "Eyebrow raising" was my reaction.

It tends to not paint the Libyian aviation authorities in a particularly good light.

bearfoil

21st May 2010, 14:47

Libya. Libyan. Habsheim, 447, Toulouse/"recorders". That's a lot of Luggage.

bear

lomapaseo

21st May 2010, 15:15

I just don't see the time delay in reading out the recorders as significant.

Sure the readers of PPRune would like instant confirmation that their speculation is correct.

Questions about the pre-crash integrity of the aircraft are easily answered in a day or two by on-site examinations in conjunction with review of ATC tapes.

The recorders are quite useful to confirm and/or examine what's going on in the performance of the crew. This should be a secondary-time-line issue and it's very important to take the time to select a venue that is free from conspiracy rumours among the seasoned investigators, with the exception of PPrune :}

Bluestar51

21st May 2010, 15:16

Roy,

What STAR would this aircraft be flying for the Locator 09 approach? Would ATC (radar vectors) normally take the aircraft off the STAR and vector to final or would the aircraft stay on the STAR until joining the approach? If on a radar vector, what altitudes would normally be assigned when cleared for the approach?

Thanks,

BS

BOAC

21st May 2010, 15:23

See post #220?

C-SAR

21st May 2010, 16:59

Ladies, Gentlemen, Naval Officers, Chaps, Guys, Galls and Mates,

Contributions to this Thread for the past two-three days have been thinning out... look at the average TBP (time between posting), although there have been some admirable efforts to keep the discussion going (see for example Takata on 735 or Ret'dF4 on 772) the discussion has been fading away.

So, let's try to get the ball rolling again.

In my view there are two areas where there is still a lot of room for debate.

Crash Site
With the latest pictures from our Man in Havana (post: 721/722) and the Takata's video clip analysis (post 735) we (collective "we" referring to the panel of experts, not the Royal We) still have to reach consensus on how this thing ended on the ground.
My personal observations from all the sources available so far are that the site in nearly one Km long and it is straight like an arrow; that at the beginning from impact point to the perpendicular road there are few pieces of debris; that the parallel mark from the impact point onwards could be the fuselage scraping the terrain; that the tail could have shredded when the aircraft hit the perpendicular road, launching the aircraft in the air minus tail and starting the destruction sequence.

This is the first area of further debate. Those interested in this area, remove the thump from its resting place and put your brains in action.

Pre-crash Events
So far we have heard many highly professional accounts of what an A330 is capable of doing. We all agree that an adequate crew, with adequate experience and training, like the one most probably was at the controls (because until disproved this is the assumption we must work with) when getting to MDA and not being visual will go around and start again. We have heard how difficult it is to force an A330 to do something "wrong", we know how many audios, alarms, etc. are there to stop us from messing up our NPA, so the question for those experts who want to contribute to this area is:

What can make an adequate crew crash 1.5 Km short and 150 mt wide?

100% has already done some good calculations and made some comments on the altimeter setting. But what happens with the RadAlt?
(This is for you experts of A330) how will the EGPWS and the RadAlt and all the gizmo you have help you to determine an incorrect altimeter setting? Was it fatigue?
Was it a technical failure of the equipment?
Or was it that the flying pilot was not used (in the sense of practiced, trained) enough on this procedure? [This is an easy one becuase the CVR will tell us who was seated where... and you understand what I mean]

So, all the good minds, back to work!! Keep the steam coming!!

We owe it to the crew and the passengers that sadly are not with us anymore, but owe it also to all those thousands of silent readers that revert to this site looking for the opinion of the Professional Pilots.

One last request to another group present in this Thread: The Trolls...
Yes I know, we do not want them, etc.
I respectfully disagree.
We need them, because, when thinking hard to solve problems, sometimes a good laugh is always welcome!!!
So for the trolls, here is an assignment for you too:
Yesteday one reputable news site, referring to the Polish President crash, mentioned that The aircraft was flying 15 meters below the tarmac
Trolls: Go Figure It!!

C-SAR

GarageYears

21st May 2010, 17:11

C-SAR:

I believe that at least one engine detached before the tail broke off, can you confirm this from your site inspection? I believe the first engine position can be determined from post #256 (last pic) and then post 267 to give a distance perspective.

I have not seen anything regarding the second engine.

Thanks for all your great work on the ground.

- GY :D

C-SAR

21st May 2010, 17:54

GY

My guess is that the engine you mentioned is about 80 to 100 meters pass the tail to the left of main debris field axis.

I can't place the other one. I looked again at the initial video clips shown in the media and there is something that could be an engine (but it might also be a piece of fuselage skin) in the area of the building at the corner of the perimeter fence, another 100 or so meters further forward and to the right of the field axis.

C-SAR

aterpster

21st May 2010, 18:23

Lomapaseo:
I just don't see the time delay in reading out the recorders as significant.

Have you participated as a member in a Western Europe or U.S. air carrier accident investigation?

The CVR/DCVR is considered to be of the highest priority. A premlinary of the FDR/DFDR is not far behind.

bearfoil

21st May 2010, 18:29

C-SAR

An easy guess would be the pilot thought he was lined up, had a distraction when looking into the rising Sun, add in the mist of Dawn, and just when he "found" the runway he had been tracking, it was an insignificant road with a line of lights that mimicked approach lights.Instead of having the 1000 feet of altitude his brain told him (by deducting a 40 foot width of road that looked like a 175 foot wide runway means we're at.....1000 feet...... instead he was at 40 feet, sinking and engines low.

A friend a long time ago had a similar event. On his third approach to 19R he saw the approach lights and chopped his throttle expecting to see asphalt any second. It was night, and he landed on the roof of a MACY'S Department Store. Only eight people died. He had flown several hundred traps in Corsairs, a distinguished civil pilot with 30000 hours. The "Approach lights" were parking lamp standards at the Mall 1000 meters right of the threshold. RIP Jim.

As for the debris and trajectory, by now it seems fairly well thought out. Tail left early followed by a belly plant at the vicinity of the Main Gear. The wing box, wings, and fuselage bounced high, but the nose was heading low from the loss of the tail, so it planted nose first and the fuse pole vaulted over the forward body which was wheelbarrowing into the rock and gravel. The wings, together still though broken at the rear box, launched another several hundred meters and flopped down in near normal orientation, separating from the wing box which had fallen off just before the two wings came to rest. In this debris Hell, there lived a ten year old Dutch boy, who was no doubt in shock that he was alive.

rgbrock1

21st May 2010, 18:51

bearfoil:

In your scenario how do you explain the total devastation of the aircraft?
I'm not saying your scenario doesn't fit, it just doesn't seem to match the obvious devastation.

C-SAR

21st May 2010, 19:07

it was an insignificant road with a line of lights that mimicked approach lights
Bear, I drove that road and there are no lights. Having said that, the rest of your description seems plausible.

C-SAR

C-SAR

21st May 2010, 19:17

In your scenario how do you explain the total devastation of the aircraft?

rgbrock1, this is one of the issues still to be clarified. The long debris field and the lack of noticeable "craters" points to a relative fast and flat impact.

On the absence of big(er) pieces, I have seen recently some local pictures with substantial chunks of fuselage skin, several meters long and aslo one where a wheeled bulldozer is riding in the debris field.
Could it be that the big pieces have been moved and we do not have pictures of them?

C-SAR

PT6A

21st May 2010, 19:40

"(This is for you experts of A330) how will the EGPWS and the RadAlt and all the gizmo you have help you to determine an incorrect altimeter setting? Was it fatigue?"

Easy... many airlines have a callout.....

When the RADALT says something you do a baro crosscheck... as a catch for wrong pressure setting.

Easy at HLLT too as the terrain on approach to 09 is pretty flat.. so not many RADALT fluctuations....

I think the RADBARO crosscheck is a great thing to be in SOP's it only takes a moment and if done everyday as a required check, one day it may save your bacon...... (well no bacon in Libya.. but you get the picture)

PT6A

fireflybob

21st May 2010, 19:44

"(This is for you experts of A330) how will the EGPWS and the RadAlt and all the gizmo you have help you to determine an incorrect altimeter setting?

Altitude/Height Check as shown on instrument approach chart against raw data (e.g. DME)

C-SAR

21st May 2010, 19:48

Thanks PT6A.

So, everybody: How will an adequate crew disregard all the warnings and penetrate MDA until hitting the ground?

Opinions, gut feelings, technical explanations, experiences, etc. The floor is open...

C-SAR

PT6A

21st May 2010, 19:54

Lack of SOP, poor crew cockpit discipline, complacency (being at home airfield) fatigue....

These are all issues which could of allowed the crew to overlook their position on the approach. (if that is what happened - prime candidate IMO)

Factor in that some of the NAVAIDs were not working... don't hear a QNH correctly etc etc and you soon end up in a situation where you could do something silly.

Good SOP's are aimed to catch things from slipping through the net - but they depend on cockpit discipline.

PT6A

C-SAR

21st May 2010, 19:59

PT6A

In your opinion, is the A330 an aircraft that will "leave you behind" if you are not alert enough or tired or following loose SOPs?
You know what I mean by being left behind by your plane..

C-SAR

jcjeant

21st May 2010, 20:20

Hi,

bearfoil

A friend a long time ago had a similar event. On his third approach to 19R Sunvalley Mall - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Sunvalley_Mall#1985_Sunvalley_plane_crash)

1985 Sunvalley plane crash

On the evening of December 23, 1985[3], two days before Christmas, a twin-engine Beechcraft Baron, executing a missed instrument approach procedure from an approach to runway 19R of Buchanan Field Airport, lost control and crashed into the roof of Macys, killing the pilot and two passengers and seriously injuring 84 Christmas shoppers in the crowded mall below, mainly by spraying them with burning fuel. Four of the victims on the ground later died from their injuries. The accident brought increased local opposition to the airport, and caused Pacific Southwest Airlines (now part of US Airways) to delay scheduled passenger service that had been planned to start at the beginning of the new year.

The airport had been closed due to thick fog a few hours earlier and the pilot (who was a student flying with an instructor) attempted to land anyway. After failing to spot the runway at the point where a missed approach should have been made he continued the approach in the hope of finding the runway farther along. When this failed he finally began the procedure for a missed approach. He had to do several things at once: Raising the flaps and landing gear, adding power to both engines, and making a left turn. While he was distracted by these activities he failed to notice the nose of the plane dropping. He lost altitude and struck the building.

Sunvalley Mall Crash (http://www.check-six.com/Crash_Sites/SunValley_Mall_Crash.htm)

Seem's a student pilot error .. or it was the instructor in command ?

jshg

21st May 2010, 20:22

The A330 in particular will bite you if you are a little high, with a tailwind maybe, and you increase rate of descent. The autothrust reduces power from pretty low to idle, and can be quite relaxed - lazy - if you then pull up again (on the profile). It will often allow IAS to fall well below required, particularly with winds light or tail. Below 100ft radalt the autotrim freezes, so if you were doing (say) a 4 degree slope at 100ft then trim will freeze at that value.
Now imagine a very low G/A after the above approach. Power is at idle, and on the 3-spool Trent at least takes ages to produce meaningful thrust. Autotrim has put the aircraft into a 4 degree slope so a harder pull than normal is required. IAS is below the bug, possibly still reducing, and although the engines are accelerating they are still at little more than idle thrust.
This may have nothing whatsoever to do with this incident, but I put it in for what it's worth.

lederhosen

21st May 2010, 20:40

The QNH was 1008 so about 150 feet difference from 1013. The minimum was 620 feet (358 above ground). Even with the wrong setting there should have still been some margin for a go-around. Tripoli is not exactly thousands of feet up.

I also do not understand why they flew a non precision approach in light winds to land on 09 rather than an ILS on 27 particularly when taxying time and the rising sun appears to favour a landing on 27. Is there some prefered runway or other reason for this?

Crashing a widebody at your homebase is quite a feat but I guess complacency and fatigue must play a role. At least we won't have to wait too long for a verdict from the recorders.

It has not been a happy 12 months for the 330 however good it looks.

C-SAR

21st May 2010, 20:51

The reasons for selecting 09 instead of 27, particularly with a little wind from 270 are unknown.

Some of the participants who are regulars into Tripoli suggested that TWR prefers landings for 09 early in the morning, but we do not know for sure if this was the case here.

CVR will tell us... maybe?

C-SAR

GarageYears

21st May 2010, 21:03

A friend a long time ago had a similar event. On his third approach to 19R

and

On the evening of December 23, 1985[3], two days before Christmas, a twin-engine Beechcraft Baron, executing a missed instrument approach procedure from an approach to runway 19R of Buchanan Field Airport, lost control and crashed into the roof of Macys

Not quite the same thing here... the crash at Sunvalley occurred while executing a missed approach, and seems a little different than our friend 'bearfoil' indicated. :hmm:

- GY

bearfoil

21st May 2010, 21:29

rgbrock1

A belly in is hard to envision, the brain wants to take us in many unhelpful directions.

Think of it this way. A 334,000 pound airliner is descending at 2500fpm at a speed of 140 knots. Without being able to arrest descent, or diminish a/s, the airliner contacts the ground (let's say concrete) at the same ROD 2500fpm, and a (now) groundspeed of 140 knots.. The descent in lay terms is roughly 30 miles per hour, Thats a fall from a three story building. No big, right? 334,000 pounds at thirty miles per hour is an unthinkable amount of energy. The a/c hits and the first snapshot shows a two foot section scraped off at the tail rise. roughly 2000 pounds has hit and given its energy to the concrete and to the smithereening of its aluminum. The next snapshot shows a section two feet more deep, a larger section and this time 7,000 pouinds of mass gives it up for friction, disintegration and a very, very minor dissipation of energy of 325,000 pounds of the mass remaining. Third snap, fourth, etc. As the mass is heating itself and the concrete, shredding its metal, the tail has slowed with an energy its mounts cannot survive, it snaps off, and is left behind to tumble and pose for the photographers. The down force it has provided the fuselage to keep the nose up is instantly missing, and the nose starts to drop dramatically. Now the wing box, landing gear, and engines contact the ground. Perhaps 100,000 pounds of mass this time, and it bounces like you cannot believe straight up into the sky, with very little of its energy missing. The trucks of the Main gears have been evaporated, the only piece left is the strut, and it bounces out of its pillow block mount in the wing box like a toothpick. The Nose, having slammed down intensely onto the rock and gravel, disappears into pieces the size of a credit card. The rest of the fuselage has been lifted up behind the nose, and continues along like a plow, as if it was entering the earth itself, except it isn't it is disappearing as the nose did ahead of it. the wings now have the appearance of a boomerang, though undoubtedly the box connecting them is broken. They have a low trajectory, perhaps rolling slowly about the spanwise axis of this 80,000 pound "boomerang". They eventually slow, and drop, roughly in designed for orientation, but the left engine pylon has pierced the upper left wing, and acquired a chord wise rip that at first glance looks like a canoe (Flap fairing). The leading edge is separated full span, yet the ribs, stringers, spars and portions of the center box remain, amazingly robust, considering their experience.

A Ferrari dropped from 30 feet at 140 knots would look the same, substituting component parts. I worked in accident investigation for a time, for attorneys. I quit when they embellished or downplayed my findings before the Court.

jcjeant that's the one.

GarageYears have it your way. I know the story, and without putting a too fine point on it, these two accidents are eerily similar to me. (If indeed the 330 succumbed in this way, so it's really not germane to debate, we don't know the widebody's procuring cause), Jim Graham was the flying pilot. cheers.

bear

sabenaboy

21st May 2010, 21:31

Opinions, gut feelings, technical explanations, experiences, etc. The floor is open...
... autopilot disconnection at MDA, thrustlevers to TOGA and pf forgetting to pull the sidestick...

...crew simply going below MDA looking for the rwy...

OR

-copy from PT6A, post 800-
"Lack of SOP, poor crew cockpit discipline, complacency (being at home airfield) fatigue....

These are all issues which could of allowed the crew to overlook their position on the approach. (if that is what happened - prime candidate IMO)

Factor in that some of the NAVAIDs were not working... don't hear a QNH correctly etc etc and you soon end up in a situation where you could do something silly.

Good SOP's are aimed to catch things from slipping through the net - but they depend on cockpit discipline."

BOAC

21st May 2010, 22:08

I also do not understand why they flew a non precision approach in light winds to land on 09 rather than an ILS on 27 - of course, not only are you assuming it was serviceable but switched on for 09 arrivals? You are in TIP.:rolleyes:

PT6A

21st May 2010, 22:26

Does anyone know for sure if the report will be made public?

I think it will come out in the end as I think the Dutch are going to be very keen to get this into court should this be anything other than an "accident"

But in the past have accident reports from Libya been public information?

Or else all those saying wait for the report... well that day may never come!

PT6A

MainDude

21st May 2010, 23:04

Maybe someone mentioned this before, but having been in a similar situation (albeit with a bit more altitude) - approaching into the sun without a contrasting background can be very misleading to your senses. You can't really see the horizon. With TOGA thrust suddenly selected, your body will interpret the acceleration as being thrust upwards and tumbling over backwards.

If the crew didn't get their eyes inside quickly to verify the climb (as opposed to just feeling it), the whole thing would have been almost over before they realized their mistake. They may have pulled back, but not enough. With a non-fly-by-wire aircraft, it pitches up automatically - but FBW stays where you left it...

The aircraft appears to have been relatively light - only 100 pax, fuel burned off. Selecting TOGA thrust must have had a significant feeling of acceleration. Combined with home-base complacency, get-there-itis, inexperience, fatigue, ... recipe for disaster. Just my 2c worth

mike-wsm

22nd May 2010, 00:10

bugg smasher

22nd May 2010, 00:35

Yep, he's not just another troll from Trondheim.

Danny has had to take him to the woodshed a couple of times over the years for lack of political correctness though...http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/smile.gif

Guess so Bubba, but I imagine Danny recognizes woodshed material when he see's it. He be 747 skipper of considerable experience himself, 400 vintage from what I gather. And BA bull-pucky notwithstanding, a trip to the woodshed is a badge o' honor round here, as far as I can tell...

GarageYears

22nd May 2010, 01:33

bearfoil:

Totally agree with your point regarding energy dissipation and I suspect another aspect not so obvious is the sand/rock nature of the contact. That would seriously exacerbate the result of the structure hitting the ground.

As for Sunvalley I was confused (and still am) how you draw a similarity between the incidents, aside perhaps from loosing situational awareness perhaps. Anyway, no biggie, cheers indeed.

- GY

vapilot2004

22nd May 2010, 02:28

I have been told that diplomatic maneuvering is the real cause for the delay and it relates (not surprisingly) to no small amount of historical distrust that exists between the two countries.

No doubt if this is ever questioned by mass media, some benign explanation will be proffered for public consumption.

PA-28-180

22nd May 2010, 04:04

GY...

"As for Sunvalley I was confused (and still am) how you draw a similarity between the incidents..."

I believe that Bear Foil was simply drawing a similarity to the possibility of optical illusions caused by low vis, i.e., a narrower than normal runway causing a pilot to believe he is higher than he actually is, or the lights in a parking lot looking like runway approach lighting, etc.

I flew out of Buchanan at the time of this accident and for many years after, and actually lived very near Sunvalley mall at the time of this terrible accident - just about 1 mile away in Pleasant Hill....as you can guess, everyone was talking about it.
Bear...though it's been a while since, I'm truly sorry about your friend.

lederhosen

22nd May 2010, 07:12

One conceivable scenario is that they expected to land on 27 and set the minimum for the ILS. Then something occured which distracted them. A medical emergency has been suggested in earlier posts.

They decide to expedite by landing on 09 but fail to brief properly. It is no big deal they think, with clear skies, homebase, and Fifi flies herself anyway doesn't she? They forget to set the QNH. Bit hot and high so they have trouble stabilising the approach with the tailwind. But it is all in a good cause, getting the sick passenger on the ground asap.

The early morning fog combined with the sun makes it difficult to see anything. They sail through the minimum and very low above ground realise their mistake and attempt a go-around which as jshg has explained can be tricky in this scenario. The plane impacts the ground and breaks up in the fashion Bearfoil so vividly describes.

Be interesting to see how much of this speculation turns out be correct once we get the report.

andrasz

22nd May 2010, 07:37

another aspect not so obvious is the sand/rock nature of the contact

Mentioned back a couple of hundred posts ago, but probably lost in the clutter:

I'm intimately familiar with various desert surfaces of the eastern Sahara. The desert surface along the northern coastal regions of both Libya and Egypt are gravely plains with clay consolidated sand mixed with gravel extending to a depth of several metres (several tens of metres in places) before bedrock is reached. While I have not actually been to the accident area, from the photos I'm reasonably certain the ground here is no different.

Such a surface is quite firm against vertical compression (will support a car with hardly any noticeable sinking of wheels, and in some places would probably support even an aircraft - at several airports of the region you may see derelict aircraft simply pulled off to the sand), however it is actually quite loose, a hole can easily be dug even with bare hands. In a relatively flat impact scenario, this surface would act more as a shock absorber, having properties somewhat similar to engineered arresting materials. It would dissipate a lot of energy quite fast, and being soft would not directly cause much structural damage. An aircraft landing on it at a shallow angle would probably remain structurally intact (minus landing gear, which would likely shear off, but greatly cushioning impact at the same time), comparable to what one would expect when making a hard landing on a runway. Correct me if I'm wrong, but AFAIK certification standards involve demonstrating no loss of structural integrity if the aircraft is flown into the runway at normal approach descent rate/speed with no flare whatsoever.

I still believe that for the kind of disintegration we are seeing here, the aircraft must have impacted at an unusual attitude.

Tom355uk

22nd May 2010, 10:24

I don't go with any of this. I think the crew were perfectly competent professional pilots who were wide awake and landing at an airport they knew well, warts and all. I think there was a software or hardware error that caused the plane to fly itself into the ground while the crew did all they could to disengage and take over control.

:=

Do everyone a favour and crawl back under your rock. You clearly have no idea what you are talking about. I will quite confidently say that it is physically impossible for any airliner, let alone a modern, safe type like the A330 to 'fly itself into the ground' as you so succintly put it. Pilots fly aircraft into the ground, not computers. If, by definition they were not paying attention and the aircraft descended into the ground under full control, then they are not 'flying the aircraft' as they should have been.

Computers don't just 'do things wrong', but their human operators bloody do. Trust me, I do IT support.

:ugh:

WFLineage1000

22nd May 2010, 12:30

Sorry to be offtopic, but computers can do things wrong. Trust me, I am in IT too ...

Tom355uk

22nd May 2010, 13:03

Sorry to be offtopic, but computers can do things wrong. Trust me, I am in IT too ...

Firstly, you will know as well as I do that those errors that occur are almost always down to human errors in source coding. I do not do avionics (and looking at mike-wsw's profile he apparently did - so he should have known better) but I know that they are highly customised embedded systems, with levels of certification, testing and criticality many times higher than normal. It is, for all intents and purposes, impossible for any safety critical bugs to make it through to aircraft in revenue service. The levels of redundancy (The A330 has three FCC's) further reduce the likelihood of software failure causing a catastrophic event such as this, and comments like the previously mentioned poster's do nothing but provide fuel for the hysterical, uninformed drivel bandied about regarding the safety of FBW aircraft - Airbus in particular.

main_dog

22nd May 2010, 13:15

I will quite confidently say that it is physically impossible for any airliner, let alone a modern, safe type like the A330 to 'fly itself into the ground' as you so succintly put it. [omissis] Trust me, I do IT support.

Hmmm, tell that to the Bilbao A320 crew...

ASN Aircraft accident Airbus A320-214 EC-HKJ Bilbao Airport (BIO) (http://aviation-safety.net/database/record.php?id=20010207-0)

This is going a bit OT perhaps, but computers most definitely "do things wrong" occasionally, sometimes because of programming inadequacy (system unable to deal with unforeseen circumstances that the software engineers had not catered for), other times I have seen autopilots/FMCs in "modern, safe types" like the A321 I flew for years (or the B744 I fly now) do absolutely inexplicable things, almost like a computer "brain f@rt". Trust me, I fly them! :}

Might not have anything to do with this accident though.

MD

Right Way Up

22nd May 2010, 13:45

I was agreeing to you until that last sentence.

Computers don't just 'do things wrong', but their human operators bloody do. Trust me, I do IT support.

obiwan78

22nd May 2010, 13:57

Why did the first Ariane V rocket crashes ? It seems to me that there were no pilot on board.

computer jockey

22nd May 2010, 14:15

Why did the first Ariane V rocket crashes ?

Due to bad programming, not a bad computer. And inadequate testing and system control.

ESA Portal - Press Releases - Ariane 501 - Presentation of Inquiry Board report (http://www.esa.int/esaCP/Pr_33_1996_p_EN.html)

Quote:
Although the source of the Operand Error has been identified, this in itself did not cause the mission to fail. The
specification of the exception-handling mechanism also contributed to the failure. In the event of any kind of exception, the
system specification stated that: the failure should be indicated on the databus, the failure context should be stored in an
EEPROM memory (which was recovered and read out for Ariane 501), and finally, the SRI processor should be shut down.
It was the decision to cease the processor operation which finally proved fatal. Restart is not feasible since attitude is too
difficult to re-calculate after a processor shutdown; therefore the Inertial Reference System becomes useless. The reason
behind this drastic action lies in the culture within the Ariane programme of only addressing random hardware failures.
From this point of view exception - or error - handling mechanisms are designed for a random hardware failure which can
quite rationally be handled by a backup system.
Although the failure was due to a systematic software design error, mechanisms can be introduced to mitigate this type of
problem.

411A

22nd May 2010, 14:47

Computers don't just 'do things wrong', but their human operators bloody do. Trust me, I do IT support.

After forty years in professional airline flying, I rather think that this poor fellow has no idea about airline flying...nor much of anything else in aviation.:ooh:
Sounds like a 9-5 desk jockey to me.:rolleyes:

RatherBeFlying

22nd May 2010, 15:01

Computers don't just 'do things wrong', but their human operators bloody do. Trust me, I do IT support.Computers are quite good, but they do have hardware failures, Sometimes the computer catches the failure and sometimes it doesn't -- I've worked on instances of both.

And of course it's humans who design and program the things and make all kinds of mistakes -- sometimes with the assistance of users who attempt to do things never imagined by the designer:}

obiwan78

22nd May 2010, 15:17

First english is my third language, so be fine with me.

On the first fly of the Ariane V they use the software (ADA software) of the old rocket with the parameters of Ariane IV. Since Ariane V capability are upper Ariane IV, this software understand that the rocket was out of direction/line. But it wasn't. So the the computer raise an exception that will send an order to self-destruction. Please to see you !

Neptunus Rex

22nd May 2010, 16:34

It is not "a computer." On the FBW Airbuses, there are five Flight Control computers. They are designed and built by two independent companies, to avoid the duplication of any software glitches. For one computer to fail is rare; for two computers to fail on the same flight is rarer still. Even if all five were to fail, the aircraft can be flown manually, via the elevator trim for pitch and the rudder for roll. Sluggish, of course, but manageable and practised in the sim.

GarageYears

22nd May 2010, 17:09

I presume this was not the very first time an A330 had (attempted to) land(ed) at Tripoli? Assuming not, if the "computer" did it, how come these other flights managed to land OK. Did the computer just decide that this time it was going to screw up?

I have worked with computers for my entire life and find this whole line of discussion just plain wrong. The code running in the Airbus family is embedded, and quite different from the run of the mill home/office PC code we are so used to locking-up/crashing.

The code we're talking about here is much more akin the engine management system of your car (admittedly many times more complex) but (this important) the code is running as a single thread, dedicated to the computing platform itself, NOT parasitically balancing on top of a general purpose operating system like Windows or similar, that is designed for you to run Word, iTunes, your email, and any number of other applications all at once, and allow you, the user to switch them in and out at random.

An FMC runs FMC code. That's it. So the problem of testing it, debugging it, and error handling are in fact much simplified. Also the code itself is subject to REAL testing, unlike the majority of domestic/office code that is in the main left to trial by fire testing with beta testers...

Also, as another contributor has already pointed out, these systems are multi-redundant, and have at least 2 suppliers that developed code entirely independently.

I'm not saying these systems are infallible - but the problem is the USER. Despite all the protections built into these systems, if the pilot commands the aircraft descend, then descend it will.

Much more likely in this case is that the crew thought they were somewhere different than they really were and, due to a combination of sun, haze, and perhaps fatigue (other posters have already crafted similar and better written scenarios for this), got the aircraft into a position that was unrecoverable, no matter what automation was available to them.

- GY :8

Tom355uk

22nd May 2010, 17:52

Ok, the IB A320 incident - that doesn't seem as though it was any sort of software/hardware failure. The aircraft was caught in an unusual and difficult situation just before landing, which would probably have resulted in a hard landing in ANY aircraft. However, if the CAPT priority button had been pushed, as per the FCOM, it seems as though it might not have happened quite so firmly. Still, nobody was hurt.

After forty years in professional airline flying, I rather think that this poor fellow has no idea about airline flying...nor much of anything else in aviation.http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/icon25.gif
Sounds like a 9-5 desk jockey to me.:rolleyes:

I should hope you are not directing those snotty comments at me.

I'm not pretending to know anything about airline flying. All I stated was the fact that aircraft do not crash themselves. You cannot, regardless of your experience (which I do respect, even if you do not respect me) tell me otherwise. I was even more disappointed that the original comment regarding soft/hardware failure came from someone who, if their profile is true, should know far better than to post such sensationalist drivel.

So what if I work 9-5 behind a desk? (It is 9-6, actually :() Just because I'm not fortunate enough to have had the chance to make a career as a pilot (yet), it doesn't mean I don't have a valid contribution to make to this thread - a contribution since vindicated by both Neptunus Rex and GarageYears.

As an aside, I always make a bloody thorough effort to make sure that I research my comments fully before posting, contrary to a majority of posters on this (and other) forum. I also happen to have a deep and lifelong passion for aviation - if you have decided that I know nothing, I hope that makes you feel better.

C-SAR

22nd May 2010, 17:55

Today I got out of Dodge City...
While pushing back in our little 737-400 (as a passenger, of course) I was looking at the A330 parked next door. Particularly I was looking at the position of the horizontal stabilizers in relation to the fuselage axis and to the bottom of the fuselage and I was comparing that to my visit to the crash site, to the first print, to the cactus cuts.... Now, if the aircraft was leveled or pitch down there is no way the HT could cut the cactus where it did (the cuts are no more than 1 - 1.5 meters from the ground)
I am going to do some drawings and calculations when I get home, just to determine (if possible and always keeping in mind that these are empirical calculations) what sort of AOA the aircraft should have to produce a cut with the HT 1.5 meters from the ground. Also one of the pictures that shows the tail complex shows the angle at which the HT were (it looks like a healthy full pull up) Experts of A330 please look at that picture and express your thoughts if you think that indeed the position of the HT shows a pitch up command.

Any help on doing the drawings and the calculation of the HT position is more than welcomed. Refer to the pictures and diagram already posted days ago.

Thanks

C-SAR

SLFinAZ

22nd May 2010, 18:39

I couldn't disagree with statement any more strongly. The real question here isn't the quality of the software but the quality of the documentation and the motivation behind the software.

1) The primary purpose of the software appears to be engineering "pilot error" out of the equation and to allow for an overall deterioration of pilot quality. Instead of the software allowing for management of complex tasks in a fast moving environment it is being utilized to perform standard tasks in normal operating conditions. in effect the software is flying the plane and the "pilot flying" is monitoring (supposedly).

2) Not only do we have ongoing issues relating to "what is it doing now" but the software flies the plane...literally until it can't and then hands off a plane that by definition is beyond the capability of the AP and accordingly far beyond the capacity of many current airline captains to intuitively recover.

The simple reality is that current FBW software is contributing tremendously to the erosion of overall skills in the cockpit and a direct contributing factor in the increase in accidents directly attributable to the lack of hand flying ability being demonstrated again and again.

At some point either we go back to pilots actually piloting or we just turn automated airplanes over to bus and trolley drivers...

GarageYears

22nd May 2010, 19:07

The primary purpose of the software appears to be engineering "pilot error" out of the equation and to allow for an overall deterioration of pilot quality. Instead of the software allowing for management of complex tasks in a fast moving environment it is being utilized to perform standard tasks in normal operating conditions

:eek: Am I reading this right? You believe the intent of the software is, as it's primary purpose, to allow for an overall deterioration of pilot quality? Bulls:mad:t. Now that doesn't mean some pilots don't take excessive advantage of automation leading to a deterioration in piloting skills, but as many of the old hands on this forum have repeated - basic flying skills MUST still be practiced, and many SOPs encourage this (though true enough, others don't). But that was NOT what Airbus designed into the software.

(I don't disagree with your first point - engineering pilot error out of the equation - for example stall protections).

- GY

fireflybob

22nd May 2010, 19:10

basic flying skills MUST still be practiced, and many SOPs encourage this

GarageYears, my experience is that most SOPS encourage full use of the automation and in fact discourage hand flying!

mike-wsm

22nd May 2010, 19:30

Has anyone on this thread stalled this plane? Could you talk us through what happens, please? Yes, I know you can't stall it, but what actually happens when you fly it slower and slower? Does it sink, spin, drop a wing? What is the aoa? Does it recover or does it go on dropping? Sorry, not trying to be sensational, just trying to understand what happens when it flies slowly.

gums

22nd May 2010, 20:07

Salute!

Compelled to post concerning this sorry story of a fatal crash. Won't comment on the "sorry" comments, however.

1) I am constantly amazed at all the autopilot and flight control "laws" for the AB. Scares me.

I realize that many "modes" and "functions" are intended to reduce crew workload and enhance overall safety. But somehow I have this feeling that the plane is just too "cosmic", and needs to be simplified.

2) I flew the first operational jets with a fully fly-by-wire system. My name ( callsign) is well-known in the community. And I did it years and years before the first FBW Airbus. Just establishing a small amount of credibility so nobody thinks I am a troll or computer flyer.

Our operational requirements were vastly different than for the commercial airliners. I understand all that.

What I have trouble with are all the fine points here that discuss such-and-such autopilot mode and such-and-such flight control mode and the various connections between them. It is personally disturbing to me. Someplace there must be a mode or law that allows the actual human being to command full power or full climb/dive command ( all with due respect to basic flight control computer laws) and eliminate all the "competition" between the various systems.

Continuuing...... The GD FLCS ( flight control system) folks refused to allow our autopilot to do much of anything. Sure. We had some basic functions like altitude or heading hold, but the FLCS had its own rules and at certain AoA's, the plane would descend even if altitude hold was engaged. It didn't even allow the AoA to reach normal limits that could be achieved if we had the autopilot turned off. One fatal due to that issue, BTW, and was simple pilot error by not monitoring altitude. 'nuff said.

3) I fully understand a scenario where sun in the windshield could obscure the landing environment. I simply don't understand a decision to either manually fly or allow the gizmos to fly you below the MDA. Maybe I am too old-fashioned. And I manually landed in many situations that required a level off for a NDB (ADF) or VOR or TACAN or localizer-only approach. Granted, I could easily pull up and almost instantly climb if I had set the altimiter wrong if I saw something that didn't "look right", as I didn't have to fight all the control laws and autopilot modes and even throttle modes. No "autopilot-coupled" modes in the Viper, although there was an excellent one for ILS in the VooDoo.

So I would wait to see what the CVR says and find out if the crew was talking about what a ****ty view they had on the approach.

4) I am amazed by the small pieces of the debris field. Sheesh.

5) For C-SAR, there should be decent geometry to "guess" whether the main gear hit first or at the same time as the tail plane. The actual aircraft pitch attitude should be used and not AoA limited by the gizmos, as we must add AoA to angle of descent. Sadly, it appears that the most serious aero/physical crapola happened downstream of the recorders. Nevertheless, we can still get valuable data.
++++++++++++++++

Finally, I want to award C-SAR a few dozen "attaboys" for his relentless pursuit of the truth. Outstanding work, and most of us really admire your efforts.

Gums sends....

infrequentflyer789

22nd May 2010, 20:20

The real question here isn't the quality of the software but the quality of the documentation and the motivation behind the software.
[...]
in effect the software is flying the plane and the "pilot flying" is monitoring (supposedly).
[...]
The simple reality is that current FBW software is contributing tremendously to the erosion of overall skills in the cockpit and a direct contributing factor in the increase in accidents directly attributable to the lack of hand flying ability being demonstrated again and again.

It's all very well talking about the documentation and design quality, but you can make that as high quality as you like, and there will still be those who fail to read or understand even the basics of it ...such as what the FCC and the autopilot bits actually do, and which is "FBW".

Jetjock330

22nd May 2010, 20:22

Mike-wsm,
Has anyone on this thread stalled this plane?Yes, it does stall, outside of normal law. It is a simulator exercise we do in alternate law and it falls like a brick in a deep stall, nose down in the vertical. Don't expect much out of 14000ft!

HundredPercentPlease

22nd May 2010, 22:05

100PP,

Is it SOP for the Airbus to fly NPAs using a constant rate of descent? Is the NPA flown in MAP mode (not sure about the Airbus term) with the raw data being monitored?

BS

There's a lot of guff on this thread, so I'll take the opportunity to explain in simple terms how you fly an NDB in an A320 (the A330 I understand is identical in this respect - if any 330 guys want to point out any differences then that would be good). Small details have been omitted.

The bus has a small button which flips between HDG/VS and track/FPA (flight path angle). In track/FPA the heading window now displays a track and the VS window displays FPA in degrees. The flight director changes and a little "bird" appears, which is a flight path vector.

You can see that this is a very powerful set of controls. At the FAF you can just select a track that is the same as the approach track, and a descent angle (typically 3 degrees), taking you accurately down the approach. As the wind shifts direction and speed, the aircraft will maintain the track. As you slow down, or the wind changes, you will maintain your FPA. No need to worry about V/S!

Now, you also have a choice whether to use this "pilot selected" method, or let the FM system steer you laterally (NAV) and/or vertically (FINAL APP) - "managed" modes. In this case the airline required/allowed managed lateral and selected vertical, so we shall look at how that is flown.

You would always use the autopilot and autothrust.

Before the approach, you prepare the FMC by checking the approach, missed approach point, MDA (normally +50 on published) missed approach and auto-selected navaids. You tell it that you want Vapp at the FAF, and you put your ND into map mode, with the NDB needle displayed. You plan to fully configure the aircraft just before the FAF, so you fly the final approach fully stabilised. This minimises the workload so you can concentrate on the 2 or 3 important jobs on the way down.

On an intercept heading you would select track/fpa. You would push the heading knob to arm NAV, so that the aircraft will intercept and follow the FMC inbound track. Configure the aircraft, and just before the FAF you preselect your FPA (-2.6 degrees here) and when you want to start down you pull the knob and you will get 2.6 degrees down.

Exactly when you pull the knob is a complex subject and will vary by type, available aids and maybe some more accurate points that you can generate yourself (more accurate than a marker beacon).

You can vary your FPA on the way down to keep in line with your height/distance checks. On this NDB there are none, so you have to just maintain the rate. You cross check the raw data (NDB needle) to make sure the NAV mode is working correctly. In real life, NAV is deadly accurate.

At MDA +50 you decide and either:

Disconnect the AP and FDs, and land.
Move the thrust levers all the way forward. This gives you TOGA thrust and the AP will pitch up and fly the go around. You will follow the track you are on when you move the levers forward until you push the heading knob to engage NAV, whereafter you will fly the missed approach in the FMC.

If you descend below the database (or pilot entered) transition altitude on STD, then "STD" is boxed and flashed on the PFD. You can't miss it.

When the radalt becomes alive, you both cross check the reading with your calculated height (by subtracting approximate terrain altitude from your indicated altitude).

Hope this helps.

Some pics from the FCOM (it all looks nicer in real life!):

http://i50.tinypic.com/kbzhuo.png

http://i45.tinypic.com/34sqx3b.png

http://i45.tinypic.com/dheb1c.png

http://i48.tinypic.com/5bb41f.png

GarageYears

22nd May 2010, 22:26

:D Excellent and well written explanation. Now stand back and wait for the clockwork crew to chime in. As for the Luddites, well, 'nuff said.

- GY

Bluestar51

22nd May 2010, 22:31

100PP,

There's a lot of guff on this thread, so I'll take the opportunity to explain in simple terms how you fly an NDB in an A320 (the A330 I understand is identical in this respect - if any 330 guys want to point out any differences then that would be good). Small details have been omitted.

Thanks for taking the time to explain the A320 magic. It certainly appears to be a very good way to fly an NPA. I'm a little "old school" so I've always prefered "dive and drive" for NPAs as opposed to constant rate of descent. Kinda like I don't do circling approaches where base is downwind. :)

BS

HundredPercentPlease

22nd May 2010, 22:39

Bluestar,

Don't forget that because the bus flies a constant angle, the ROD may vary. But it's the angle that matters!

I know of no airline that operates larger machinery on a "dive and drive". It's all about stable approaches now, so you simply "bounce off" MDA or land. Levelling off at MDA is only for light a/c.

aterpster

23rd May 2010, 01:20

HundredPercentPlease:
Don't forget that because the bus flies a constant angle, the ROD may vary. But it's the angle that matters!

Amen. But, I would add that target KIAS maintained to the flare also matters a whole lot.

411A

23rd May 2010, 02:36

I know of no airline that operates larger machinery on a "dive and drive".

I do, I fly for one.
Levelling off at MDA is only for light a/c.

Nonsense, ours is a quite heavy widebody three engine jet.

Fly747

23rd May 2010, 02:50

Now we all know that you really are a dinosaur 411A if you think that "dive and drive" is the way to do it in a big jet. If not then you should be doing all you can to change your airline's SOPs.

411A

23rd May 2010, 03:13

If not then you should be doing all you can to change your airline's SOPs.

Negative, for one very important reason....we circle to land on a regular basis, so dive/drive keeps our guys in practise.
It would appear with this accident, that the crew was woefully unprepared for that 'stabilized approach' that seems to be favored so much, these days.

Considering this...dive/drive might actually be safer.
Shock, horror.:E

heavy.airbourne

23rd May 2010, 03:41

Let me add, that for serious circling approaches like e.g. SAH, ADD, or even SSG, there is a data base that lets you fly those all managed, which is available for all straight-in NPA, as well: No need to fiddle with FPA, inbd track, V/S, whatever. You must check that the data provided in the database is correct, though, as database providers like LIDO employ too many airheads to be reliable. :{ Something I wanted to point out for a long time; now, i feel better. :E
The hardest part is to transition from instruments to visual clues, that is where so many accidents happened, and still seem to happen. After a long night of flying (in Africa), it is very difficult to switch to G/A mode. It is easy to say: "If you cannot make sense of what you see, just go around!", but all mental energy to make this seemingly simple decision has been drained from you hour after hour...They call it fatigue, I reckon, and target fixation. :ouch:
If you ask to much (from your flight crews), you will get too little, eventually. We're only human, after all. :eek:

BOAC

23rd May 2010, 07:38

100% - thanks for that info. As one who has not had the option to fly such an approach, 4 questions if you would?

1) It appears that although you would be 'watching' the threshold NDB on the HSI you are not really flying an 'NDB' approach. What is the SOP should this ADF needle drift off, say 10 degrees as you approach MDA? Do you follow your FMC, correct to the needle or g/a?

2) On the basis that you are not actually flying an NDB but something generally more accurate, would you use the NDB MDA or a lower and is this sort of an approach called an 'NDB ' approach?

3) There seems to be a suggestion that this approach is neither approved or used by Afriqiyah. This would appear to be the case as I cannot see any other reason for the crew to have been flying what appears to be a VOR approach which is offset. What would your airline expect on 09 at TIP?

fireflybob

23rd May 2010, 07:47

BOAC, in the company I fly with any approach using VNAV/LNAV (and similarly on the Airbus using "managed") must be backed up by the "raw data". If the raw data shows differing information then the raw data should be followed. This obviously assumes all the raw date aids are available and coding correctly.

One for 100% on the Airbus - if the approach is in the FMGS database can you not fly the vertical profile in managed mode rather than FPA?

White Knight

23rd May 2010, 08:29

Quote:
If not then you should be doing all you can to change your airline's SOPs.
Negative, for one very important reason....we circle to land on a regular basis, so dive/drive keeps our guys in practise.
It would appear with this accident, that the crew was woefully unprepared for that 'stabilized approach' that seems to be favored so much, these days.

Considering this...dive/drive might actually be safer.
Shock, horror.

Whilst I agree with many things you say 411a I have to say that this really is Jurassic:}:} Or maybe even Pre Cambrian!!!

A stabilised approach to MDA is far more sensible than dunk slam technique - and even for a circle to land that's what we fly to MAP - if visual fly the circuit but only taking landing flap when lining up with the runway (330/340 SOP).. I for one don't really wish to be dragging 240 tonnes of 340 at maybe 400'AGL for a couple of miles - just not sane:ugh:

411A

23rd May 2010, 11:57

....if visual fly the circuit but only taking landing flap when lining up with the runway

Standard for our ops as well, White Knight.
Jurassic or not, if circling, a level segment must generally be flown, so, in reality straight in is no different, as flying level for short while gives the crew longer (at MDA) to look for the desired runway (not a parallel road, for example:rolleyes:).

Green Guard

23rd May 2010, 12:11

as flying level for short while gives the crew longer (at MDA) to look for the desired runway (not a parallel road, for example).

Ahh here we are. You need time for looking and checking the RWY...?
Would it not be enough from just before DH to decide ?
Either you see it or you do not see it....

White Knight

23rd May 2010, 12:26

Except 411a the circling minima is usually quite a bit higher than a straight in approach - the point you seemed to have missed here. At EK the circling minima is 1000'AAL or published minima whichever is higher.. I can think of several straight in NPAs that we fly with minima below 500' and I ain't dragging a heavy jet in at that altitude!

411A

23rd May 2010, 12:37

the point you seemed to have missed here.

Missed? Hardly.
We circle at the category D minimums (600-2) or charted, whichever are higher. 1000 AAL is many times not practical for our ops.

If one can fly a level segment at 1000 AAL, but unable to fly the same at 500 AAL for a short straight-in segment, I would suggest that said individual should not be assigned duties at the pointy end.:}

Would it not be enough from just before DH to decide ?
On and ILS approach which actually has a DH, yes, however, runway 09 in TIP is served only by non-precision approaches, which have no DH, only MDA.

In reality, TIP is quite reasonable.
Follow the IFR procedure to the designated runway.
Pretty basic stuff.

lederhosen

23rd May 2010, 13:01

HundredPercentPlease has explained very well how you fly this approach in an Airbus. It must be obvious even to the non experts that if the crew had flown the approach as per procedure they most likely would not have ended up as they did. We can speculate about weird and wonderful computer failures. Before we fixate on the highly unlikely why don't we revisit the most likely scenario. The crew became distracted by a medical emergency, decided to expedite landing and got behind the aircraft.

If they failed to set the correct MDA and compounded this by not switching to QNH in their focus on landing as quickly as possible they could easily have been below one hundred feet above ground rather than around 400 feet when the minimum autocallout woke them up. As a previous poster has pointed out this is a difficult situation to recover from in a 330. As the aircraft rotated rapidly into the go-around attitude the tail hit the ground hard enough to separate and the rest is history.

HundredPercentPlease

23rd May 2010, 14:11

1) It appears that although you would be 'watching' the threshold NDB on the HSI you are not really flying an 'NDB' approach. What is the SOP should this ADF needle drift off, say 10 degrees as you approach MDA? Do you follow your FMC, correct to the needle or g/a?

The approach is an NDB approach - nothing else - just using a fancy autopilot. On our fleet, we can only tune one NDB, due to terminal cheapness (most 320s have both ADF receivers fitted). If you go outside limits on the approach aid (5°) then you go around - if you another aid tells you something is wrong then that'll be one of those "airmanship" go arounds I guess.

2) On the basis that you are not actually flying an NDB but something generally more accurate, would you use the NDB MDA or a lower and is this sort of an approach called an 'NDB ' approach?

As above really - this is an NDB approach, with NDB minimums. We add 50' to the MDA to make a DA.

If you are using the GPS as the primary source of navigation (a GNSS approach), then there are hugely different procedures, checks, qualifications needed and so on. And there has to be a published procedure. We do a few of these at various places - Sharm for example.

3) There seems to be a suggestion that this approach is neither approved or used by Afriqiyah. This would appear to be the case as I cannot see any other reason for the crew to have been flying what appears to be a VOR approach which is offset. What would your airline expect on 09 at TIP?

The only thing I have read is that this is the approved approach for Afriqiyah (see below).

At our airline we have approval and training to do managed/managed approaches (unlike Afriqiyah). I would not use the VOR as it is notammed as crap. So I would do a managed/managed (FM guided lateral and vertical) NDB using company minimums of 670'. If I didn't have good visual of a runway to make a stable landing on, then I'd initiate a go around as soon as we got to minimums.

If the approach was not in the box, then it would be selected/selected.

One for 100% on the Airbus - if the approach is in the FMGS database can you not fly the vertical profile in managed mode rather than FPA?

Only if you have the appropriate approvals in place. For the first year or so at our company we didn't have this approval, so we had to fly managed NAV / selected vertical.

Giggy informed us in this post (http://www.pprune.org/5705383-post758.html) that They fly managed laterally and selected vertically Npa's.

---

As I mentioned before - for a working aircraft to end up at the ground you need to start at the wrong height (altimetry) or select the wrong FPA (and continue below minimums hoping to find the runway).

There are 2 things concerning me:

1) The aircraft is so good you "expect" to end up at minimums bang on the centreline with 2 white and 2 reds. If you can sort of see the ground then "it should be there somewhere"...

2) There is no published approach angle on the plate. You have to work it out (assuming it's not in the box) and arctans and fatigue do not mix well. Below is a pictorial guess/calculation at where you would hit the ground with various FPAs selected.

Mix 1) and 2) and the result could be dangerous. Remember also that you fly the approach "to get in". With no vertical guidance (height/distance checks) you would set the FPA to be slightly steeper than perfect, because it's best to arrive at MDA slightly too low for the visual segment than slightly too high.

http://i50.tinypic.com/2dgmgdh.jpg

SLFinAZ

23rd May 2010, 14:22

Unfortunately all to often the answer is that the PF simply isn't. Automation is eroding aviation to the point that "stick & rudder" has been replaced with "knob & button" to a large degree. A complex and difficult undertaking requiring tremendous intuitive feel coupled with years of training for contingencies has been replaced with the ability to "plug and play". Which is great...

Right up till it's not, then we see pilots incapable of basic recovery techniques in a timely manner or incapable of unusual attitude recovery that should be considered fundamental. This is not aimed just at AB but at the entire concept of a "smart plane" over a fully trained and capable flight crew.

Capn Bloggs

23rd May 2010, 15:18

If you don't have a DME to allow you to fly the correct CDA, then get to the MDA ASAP, PF level off, PM eyeballs out looking. If you fly into the PAPI from below, well and good, do it and land. If you get visual too late, GA and have another go. No point in a CDA if it doesn't take you to the runway on the correct 3° slope. You've got to have a DME (or a GPS distance in lieu, or of course a FMS DB approach) to make a CDA work.

Configure the aircraft, and just before the FAF you preselect your FPA (-2.6 degrees here) and when you want to start down you pull the knob and you will get 2.6 degrees down.

Exactly when you pull the knob is a complex subject and will vary by type, available aids and maybe some more accurate points that you can generate yourself (more accurate than a marker beacon).

You can vary your FPA on the way down to keep in line with your height/distance checks. On this NDB there are none, so you have to just maintain the rate.
When to pull is the problem. No DME? You're only guessing.

411A

23rd May 2010, 15:23

HundredPercentPlease

23rd May 2010, 16:27

BOAC

23rd May 2010, 16:29

It may be, of course, that Capn Bloggs is not aware of the relationship between G/S and R of D for a given glidepath?

ironbutt57

23rd May 2010, 17:14

recent CFIT data indicates that "dive-drive" NPA's account for the majority, and not suprising, most were inside the FAF, aligned with the centerline, and just came up short..hence the trend towards CANPA's with modern airliners...an also be done in steam gauge airplanes quite well...even in Arizona!!!

White Knight

23rd May 2010, 17:27

If one can fly a level segment at 1000 AAL, but unable to fly the same at 500 AAL for a short straight-in segment, I would suggest that said individual should not be assigned duties at the pointy end.

Didn't say I couldn't - said I didn't want to.. Bit of a difference there!!!!

Obviously your version of AZ English is different from my English (original by the way old fellow):E

If one is dirty diving still after all the evidence shows that it causes lots of prangs I suggest that that someone should be thinking about hanging up the electric hat and going into rose growing (or cactii)

Plectron

23rd May 2010, 17:31

Wow. Somebody thinks you might need to be able to actually fly. What a shocking idea. Fly meaning the autopilot/throttles are off, the FDs aren't on etc. I have recently been with the limp-wristed-and-never-had-a-real-job-incompetent-though-filled-with-righteous-entitlement with 400 hours total time and already in an intercontinental jet set (whoopeee) for a while. I guess this is what this toxic industry is coming to. I thank those who think you might someday need some chops.

411A

23rd May 2010, 18:24

I have recently been with the limp-wristed-and-never-had-a-real-job-incompetent-though-filled-with-righteous-entitlement with 400 hours total time and already in an intercontinental jet set (whoopeee) for a while.

In these cases, 'gear up and shut up' works wonders.;)
After awhile, they usually come around..:} hopefully

Bluestar51

23rd May 2010, 18:52

100PP,

No use to us who fly for airlines who prohibit the "Arizona approach". CDFA is the norm now, outside of Arizona.

There has been a lot of discussion about automation, but the last time I checked one of the largest US airlines handflies all approaches including CAT3A using the HUD. It is my understanding that handflying is part of their culture.

BS

Bluestar51

23rd May 2010, 18:55

411A,

In these cases, 'gear up and shut up' works wonders.http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/wink2.gif
After awhile, they usually come around..http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/badteeth.gif hopefully

I wonder how they feel about circling approaches where base is downwind?

BS

daikilo

23rd May 2010, 19:05

What if the PIC did just as you suggested, but from an altitiude which did not giive him adequate ground clearance?

Right Way Up

23rd May 2010, 19:08

I have recently been with the limp-wristed-and-never-had-a-real-job-incompetent-though-filled-with-righteous-entitlement with 400 hours total time and already in an intercontinental jet set (whoopeee) for a while. I guess this is what this toxic industry is coming to. I thank those who think you might someday need some chops.

I think this is what you are after! ;)

<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/gmxiZZZ-2_4&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/gmxiZZZ-2_4&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>

411A

23rd May 2010, 19:09

I wonder how they feel about circling approaches where base is downwind?

Ours do this when needed, because...they are trained to proficiency to do so.
I normally leave the circling handling to the First Officer, so I can keep a sharp look outside.
He flies, I monitor.
Much safer this way...in my opinion.
It also gives him good handling experience under a variety of conditions.
More experience now equals a better Captain, later on....hopefully:}

TWA had a term for this, long ago....it was called crew co-ordination.

Bigpants

23rd May 2010, 19:16

Just a thought but when Airbus sold the Libyans this fleet of new aircraft what care did they take over the training of crews?

Was the training carried out in house or outsourced?

Which Airbus department carries the biggest weight, sales or training?

Some us, including me, have become very adept at blaming the crews when a new aircraft flown by a rookie crew from the developing world crashes.

The usual banter, Camel drivers, Mercedes etc.

I think they deserve a better deal, perhaps Airbus and Boeing need to make sure the customer can actually operate the aircraft under local conditions before they let them go..... and sometimes maybe they should insist on more training

Bigpants

HundredPercentPlease

23rd May 2010, 19:17

Bluestar,

I am referring to the "dive and drive" where you fly to MDA and then level off looking for the runway. If you can't find it by the MAP, then you go around.

This is not allowed in our company (and many others). You have to fly a stabilised, or continuous descent approach. When you descend down to 50' above MDA you either continue in a stable descent down to the runway, or go around. It is assumed that the initiation of the go around takes less than 50', so you never bust your MDA. This old, de-stabilised method is what makes the old boys real men, but also was a contributory factor in many accidents so is now prohibited by operators with a proactive safety culture.

Hand flying is fine though, but most people choose to practice their skills by flying eyes down on fine days so the PNF can just monitor by watching out of the window. When you are in marginal WX and you need to get in, maximum use of all the aids is a wise strategy. It minimises risk, and in my company that's what I'm paid to do.

PT6A

23rd May 2010, 19:18

A few points...

100% great post... Yes the Jeppesen does not have the approach path angle - this could lead to an error with a tired crew. LIDO does show the correct angle - actually they work it out to a 3 degree approach path by starting the decent further back and arriving at minimums (670) - they also already show the CANPA minimums (620 + 50)... again just another way of avoiding a slip up with a tired crew.

The approach in Tripoli seems to me (no expert in IAP design) to be quite poor... why not make the state published procedure a 3 degree path?

For the poster who does not know when to pull without DME, the A320/330/340 are aircraft that with crew who know what they are doing are independent and not reliant on ground based navigation aids.

There are no less than 3 ways to fly the approach into Tripoli using just aircraft systems and not having to use the aids on the ground... which is a good thing as they don't work correctly!

Now a question for those really in the know with regards to approval for managed / managed can BA and LH for example do a fully managed approach into Tripoli (Legally) when the state who designed the underlying procedure does not authorise managed / managed approaches?

A few years ago at the request of Continental Airlines, in the UK several RNAV approaches were published but only for their (COA) use as they were not yet approved procedures in the UK.

PT6A

MD83FO

23rd May 2010, 19:20

egpws? terrain clearance floor?
"too low terrain!"

PT6A

23rd May 2010, 19:22

Bigpants, Airbus failed a few of their local guys.....

These guys were then promptly retested by a "local" TRE and found fit....

Draw your own conclusions....

Airbus training staff in Libya have documented their concerns.. maybe this will come to light.

PT6A

lederhosen

23rd May 2010, 20:28

Reminds me a bit of the debate after the Schipol crash. As I pointed out then a stabilised approach is important in avoiding this kind of thing happening. I would be amazed if the final report does not show a similar degree of the crew getting behind the aircraft.

I am interested why they sailed through the MDA.....maybe they were above profile (or thought you were), took out the autopilot and sailed through the MDA and below the profile, maybe they had set the minimum for the ILS the other side? Either way it seems to indicate a serious loss of situational awareness.

A-3TWENTY

23rd May 2010, 20:47

Fully agree....You don`t know what was to make the transition from the libians to the airbus philosophy...While a normal training takes about 10 sim sections , for the lybians it were taking 28 and they were beeing released in marginal minimums...

Inside Airbus there were people under the table saying that an accident was waiting to happen...

It happened...Maybe the training is takem more seriously now, otherwise a second accident is just a question of time.

GarageYears

23rd May 2010, 21:01

Inside Airbus there were people under the table saying that an accident was waiting to happen...

It happened...Maybe the training is takem more seriously now, otherwise a second accident is just a question of time.

Eventually the problem will solve itself - they only have so many aircraft....:eek:

- GY :rolleyes:

411A

23rd May 2010, 21:43

Hmmm, the label on the video says 'Copilot slaps pilot while Flight Engineer watches'.

However, the 'watcher' is not a Flight Engineer, he is the Navigator, as DC-4's did not have a F/E:}

Oh well...the younger guys wouldn't know the difference, I expect.:rolleyes:

Capn Bloggs

23rd May 2010, 23:32

BOAC,
It may be, of course, that Capn Bloggs is not aware of the relationship between G/S and R of D for a given glidepath?
Don't worry, I've got a bit of an idea. CDA NPAs, both DB and Non DB, have been routine for our ops for over 25 years. My point was that "pointing" the nose at the FAF, hoping you get the to MDA at the point where the 3° approach path/PAPI coincides with the MDA, is not the ideal way to do it. FPA is not the be-all-and-end-all: one good gust of wind, turbulence (or perhaps selection of final flap) will bump the aeroplane off the original 3° and FPA will not get you back to the intended approach path. It will maintain/re-establish a 3° FP, but not back to the original, intended descent path. FPA is a reactive control, not a pro-active, guide-to control.

The only proper way to do a CDA on an NPA is to either use the DB 3° coded approach, follow a charted 3° profile (we've had these on our AIP charts for many years - catch up world) or create your own profile using the DME or GPS to a suitable distance reference waypoint. If you can't do that, then getting to the MDA nice and early and steaming in is the way to go. Sit there fat dumb and happy. Get Visual, land. If you don't get visual, continue steaming along, level, to the MAPt then do the missed approach. Easy.

411A

23rd May 2010, 23:49

....then getting to the MDA nice and early and steaming in is the way to go. Sit there fat dumb and happy. Get Visual, land. If you don't get visual, continue steaming along, level, to the MAPt then do the missed approach. Easy.

I always thought so....and still do.;)

iceman50

23rd May 2010, 23:55

Capn Bloggs

What tosh, have you even flown an airbus.

411A

It is not just some airlines that have banned the dive and drive but STATE (as in countries) authorities as well!

411A

24th May 2010, 00:04

It is not just some airlines that have banned the dive and drive but STATE (as in countries) authorities as well!

The operative word being some.
Not where we fly, they haven't.

So, lets review.
Many say the the CDA is better, and yet....we are discussing an accident where the aircraft was so fitted with all the latest and greatest kit to do the deed, and the pilots (being factory trained) surely must have been trained accordingly...but the airplane crashed anyway.

Nope, simply not convincing.:ooh::yuk:

0-8

24th May 2010, 00:15

You're making the assumption that the crew did as they were trained....

CDA's are widely recognized as being the safest way of performing non precision approaches.

Plectron

24th May 2010, 01:48

CANPA and CDA are great if you put in the right waypoints and get your altitudes all right. I have seen some cases where folks get that all screwed up and end up with the EGPWS going nuts. It isn't hard to do,

Start your descent at the Initial approach altitude and level off at the MDA - not a lot of button pushing here to enter data incorrectly. OK- Pushing the stopwatch.

Watching some of the guys in the sim do CANPA all bets are covered but generally no one is watching the store. Lots of chatter about checking altitudes every mile but the purpose of the exercise, to get the airplane safely on the ground, seems to take a back seat.

I still do the dive and drive in my own plane. Much less work load. Single pilot no autopilot.

Plectron

24th May 2010, 01:52

By the way, factory training can be good but eons ago I attended one where 2 of the guys couldn't speak English. The instructor kept asking if they were understanding and they kept nodding their heads and said yes, yes. They smiled a lot and were in the graduation picture. A year later they were dead - killed in the plane they had purchased.

Capn Bloggs

24th May 2010, 03:08

Iceman,
What tosh, have you even flown an airbus.

What's tosh about what I said?

starvingcfi

24th May 2010, 04:32

the libyans are the only pilots that have ever given me a shaker at 1000' on final...almost happened twice. only pilots i've ever had drift left of centerline all the way to the edge, still drifting after liftoff with a 10kt crosswind. only pilots i've ever seen lose all situational awareness, inadvertantly cross the fence at ref+35, and float halfway down an 11,000ft runway...all the while pumping the controls while i have to remind them 'don't force it on. don't force it on. don't force it on.'

*sigh* glad i got out of there. :ugh:

lederhosen

24th May 2010, 06:45

There is of course the possibility that in early morning thin patchy fog you might be able to see the runway well before minimums. However as you descended lower into the murk the slant and sun caused you to lose visual reference.

I flew an early morning approach last month where we went from Cavok to CAT3 conditions in this way, fortunately reflected in the Atis. So we were doing an autoland. Otherwise it would have been a certain go-around.

It does not change the end result But it would perhaps explain how they got to be where they were.

Equally lining up on a road as suggested earlier would explain it...but at your homebase?

speedbird716

24th May 2010, 08:17

Question: There's a lot of discussion here about CDA vs. dive and drive. Was the crew trained in and executing a CDA approach or were they doing a dive and drive? It seems to me the discussion is pointless unless we know the procedure at Afriqiyah and if the approach was flown properly (which we won't know for awhile).

For my part, CDA in the A330 is no different than a CDA in a Boeing 767. CDA requires everything final before you start down (gear/flaps/speed) and if you are not where you are suppose to be at 1000ft AGL and at DP, you go around. Before anyone starts shouting at me, yes, I do know that an Airbus and Boeing handle very differently, but the procedures aren't that different.

So, what am I missing?

speedbird716

lederhosen

24th May 2010, 09:21

Well as I pointed out in the post above all could appear fine at 1000 feet or at least the pilot flying might think so. Below that height it is perfectly conceivable that a fatigued crew not terribly current in hand flying could end up unstabilised if they lost visual reference. Add a distracted crew, complacency etc. and the need to recover from an unfamiliar situation where the jet responds in a way you do not expect and some self anointed aces might have been challenged.

I too cannot see the point of the CDA versus dive and drive discussion, simply because I cannot imagine anyone flying a modern EFIS jet any other way than CDA...a jurassic jet that is a different matter.

Sitting Bull

24th May 2010, 15:33

I actually have information others don´t have and reluctantly will share some of it just to stop some of the bull...t on this thread:

-AAW771 was cleared for and executing the NDB 09 approach
-they did not report any problems nor did they request any medical assistance
-they announced and initiated a go-around at low level (tower radar and Alitalia TCAS)
-according to the official statement of the Alitalia crew that witnessed the crash, AAW771 descended out of the low clouds nose down, wings level and in one piece
-after violently hitting nose first it disintegrated with the tail separating and tumbling over

now please let´s wait for the DFDR and CVR readout to be completed

mike-wsm

24th May 2010, 17:34

Jetjock330,
Mike-wsm,
Has anyone on this thread stalled this plane?Yes, it does stall, outside of normal law. It is a simulator exercise we do in alternate law and it falls like a brick in a deep stall, nose down in the vertical. Don't expect much out of 14000ft!Thanks for that.

Clandestino

24th May 2010, 19:28

-they announced and initiated a go-around at low level (tower radar and Alitalia TCAS)

Therefore quite long debris field and severe destruction could be result of high-speed shallow dive. Those big fans might need minor eternity to spool up but once spooled will propel light A330 quite spectacularly. I'm putting my money on crew succumbing to somatogravic illusion (http://www.pprune.org/tech-log/9199-somatogravic-illusion.html) during manual go-around.

Boxes will tell their tale, anyway.

Sitting Bull

24th May 2010, 19:39

dear Clandestine

Somatografic Illusion is one scenario we´re seriously considering at this stage

steamchicken

24th May 2010, 19:48

Is it true of the A330 that the alpha-floor protection is locked out below a given radio altitude, as it is for the 320?

0-8

24th May 2010, 21:59

Yes, Alpha Floor is inhibited below 100ft on the approach.

0-8

24th May 2010, 22:11

Based on the info provided by Sitting Bull, there seems to be many similarities to Gulf Air 072 - i.e. a low altitude GA in marginal visual conditions where the PF lost situational awareness and pitched down instead of up.

Gulf Air Flight 072 - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Gulf_Air_Flight_072)

Capn Bloggs

25th May 2010, 06:16

If it was as Sitting Bull said, then it could have been similar to this go around event (http://www.atsb.gov.au/publications/investigation_reports/2007/aair/ao-2007-044.aspx).

HundredPercentPlease

25th May 2010, 08:48

Capn Bloggs,

Thank you for that fascinating link. Our lot have recently adopted those new procedures and I was not aware of the source of the problem.

If TOGA was not selected here (levers just short of the detent) and then the A/P engaged after manually pitching up, the aircraft will do exactly what you have told it to do and dive down aggressively with lots of thrust on.

But to do this you would have to:

Disconnect the A/P at minimums but forget to switch off the FD (SOP is FD off).
Not read and call your FMAs (fundamental Airbus stuff).
Engage the A/P with the FDs showing full fly down.

OR (if trying to GA with the AP on):

Push the levers almost all the way and you just accelerate downhill with an almost immediate AP disconnect.
Fail to pull up with the sidestick (as the FDs guide you down 3° slope).

If you have come from a slightly more old fashioned jet, it is instinctive to be gentle with the thrust levers. The Airbus demands a positive and rapid ramming of those levers at times.

If you are light and powerful, there is a further reluctance to ram the levers to TOGA. But ram them you must.

If you ever "fly through" the FDs in an Airbus, then you are asking for trouble*. You need to turn them off.

* Pedants: I know, apart from during the blending of modes in a V1 cut.

Bigpants

25th May 2010, 10:10

I wonder if this accident report will be similar to the Gulf Air A320 Accident of a few years ago when a combination of poor CRM, a dominant but not very capable Captain, an under confident and inexperienced co pilot managed to drive a perfectly serviceable aircraft into the Gulf at night while "going around"?

Bigpants

C-SAR

25th May 2010, 14:23

I was back on the Thread after 3 days and I was glad to see that I had 3 or 4 pages of posts to read...
I thought that some of the discussions were drifting a little too much toward the "I do, you do" which was taking us nowhere as far as the accident was concerned.
I was admiring 100%Please description of the intricacies of flying the airbus (thanks, excellent post!!)
I was thinking of posting a "Sobering Thought" stating more or less " I am sure that some of the guys and chaps from AAIB, BEA, NTSB etc. with real knowledge will be smiling at our efforts and therefore we should never forget in our postings that ours are mainly guesses, educated guesses most of the time, but still guesses, just to keep all of us focused"

Then I came to Sitting Bull post.... and the light went off!!

Not for long though.... I put the light back on and started thinking again...

I am thinking that what Sitting Bull has shared with us is a great amount of information: Thanks for sharing that with us.
Now we can go back to the beginning and drop all the speculations on good v/s bad pilots, trained v/s untrained pilots, cultural issues, etc.
Here we are: normal approach, no emergencies, nothing out of the norm, including the decision to go around and to start the GA.... so far so good.

Where I am perplexed is in the last two bullets of Sitting Bull information
-according to the official statement of the Alitalia crew that witnessed the crash, AAW771 descended out of the low clouds nose down, wings level and in one piece
-after violently hitting nose first it disintegrated with the tail separating and tumbling over

I am trying to fit this description with what I saw. Granted, I only saw a little part (and I have already said so) of the area outside the field of debris, therefore I am well aware that I do not have all the facts, nor I pretend to say so.

However, Sitting Bull statement has increased exponentially my questions!
Some examples: Where did the nose first impact occurred? How does a nose first impact tie with the debris field and the markings present on the ground? (not only from the limited pictures on the ground, but also the videos from above openly available); How did the nose eradicate the electrical poles (if it was the nose)?; How did the electrical wire ended in the tail cone?; How were the cactus cut? And many more....

Also, I do not think that there is a clear line of sight to the beginning of the debris field from holding point Rwy 09, where the Alitalia aircraft was. I think that there are several trees and bushes. Could it be that the AZ pilots saw the second part of the initial impact? Could it be that during the GA the aircraft bottomed, scraping the electrical line with the tail, hitting with the back, bouncing up, nosing down and this is what the Alitalia pilots saw?
I do not know and I do not want to speculate at this point. From my side, I will stop speculating and will wait for the report.

Sitting Bull, thanks again for the access to real information you have granted all of us.

C-SAR

RetiredF4

25th May 2010, 15:33

C-SAR
However, Sitting Bull statement has increased exponentially my questions!
Some examples: Where did the nose first impact occurred? How does a nose first impact tie with the debris field and the markings present on the ground? (not only from the limited pictures on the ground, but also the videos from above openly available); How did the nose eradicate the electrical poles (if it was the nose)?; How did the electrical wire ended in the tail cone?; How were the cactus cut? And many more....

You had been on the scene, so your statement concerning the poles and lines and the beginning of the debris field have a very strong handle, therefore aperently nobody saw any need to question your assesment.
Now, that you rise those questions yourself, i´m keen to add some points. There is no intention to downsize your work, you have done a hell of a job there.

In another non-english forum, which i can´t find anymore, the discussion over the lines and poles was also taking place with on scene pictures shortly after the crash. On those pictures a lot of undamaged lines (power or phone-lines) could be observed. On later pictures some of those lines had been gone. The outcome in this forum being, that there was no contact with powerlines prior to the contact with the ground and some of the lines had been downed later.

So could it be possible, that the lines wrapped around the tailsection are not from the initial impact area and have nothing to do with the downed lines prior to the impact area. Could those lines have been downed earlier, or could they have been damaged during rescue and salvage operations with heavy equipment? Those poles look like being 3 to 4 meters long? Depending on the way they are fixed to the poles those lines may hang as low as two meters in open area (though they would be higher over streets). A Heavy crane might well be too big to go underneath them.
At least one pole looks like it just has fallen near the place it had been standing before, not beeing dragged at all. And at least two poles look on the pictures as if they had been lying already some time. On one pole the lines had been stored in a manner, like companies would do it if they remove a section of cables temporarily.
The lines at the tail could be coming from downed lines after the initial impact area, as mentioned before there seem to bee a lot of lines in the area. Maybe the cause for the downed lines had been known to the authorities, therefore the area was accessible for you.

Considering the hard ground, the area you visited is probably the initial impact area, the initial contact shearing off the nosegear or collapsing it. The cactus can be cut from the wings or a engine nacelle. The main gear together with the strong wingbox gets overstresed in the impact simultaneously, which leads to the immidiate breakup of the fuselage and the detachement of the tail.

The bigger question with all scenarios is imho the absence of contact marks from the engines. Could a crash landing like described above lead to the complete detachement of the wingsection together with the wings and engines, thus not contacting the ground in the initial impact area but tumbling ahead of the airctraft until the final resting place at the end of the debris-field? Later contact-points with the ground would be wiped out by the onfollowing fuselage debris.

franzl

Sitting Bull

25th May 2010, 15:35

dear C-SAR

you´re most welcome

and I agree with you that the Alitalia witness report is just that: a report of what they witnessed.

whatever happened before AAW771 came into their view remains to be extracted from the DFDR and the CVR (work in progress)

HundredPercentPlease

25th May 2010, 16:20

I am trying to fit this description with what I saw

To me the trench looks like it's made by the front of the aircraft going in at a shallow angle but with high energy. The front half of the fuselage is fully destroyed (small pieces), the tough wing box and wings carry on forwards, the rear is destroyed in bigger pieces (as the energy is reduced) until the tail arrives and is left intact.

As has been said - any more has to come from the recorders.

C-SAR

25th May 2010, 18:54

Ret'dF4

Thanks for your post. I fully agree with you that there can be other explanations for what I saw. I tried to convey that thought few pages ago when cautioning that my visit was just a peek, a blink of the eye. Of course only a thorough, long and detailed inspection of all the elements in the crash site can lead the investigators to draw conclusions.

Thanks again for your comments. I am sure most of us will read with great interest the final report, when it will be published.

C-SAR

daikilo

25th May 2010, 20:44

You informed us of what you saw and, possibly without realising it, what you did not see. What you saw was likely is close to fact as is reasonable given the time delay and movement on the site. Investigators will have already interpreted what you and they saw.

Others interpreted your info and combined it with info from elsewhere. Let's see how close the recorder dump is to the speculation on this thread. My guess is that you will be in the 5% who's inputs are consistent with the reality.

Thanks again.

gums

25th May 2010, 21:08

Salute!

I have to add to the many accolades about C-SAR's exemplary inputs.
+++++++++++++++++++++++
I also wonder about all the modes and laws and such that seem to be the vogue, or even the basics of flying the Airbus.

Is there any button the pilot can hit that allows him/her to fly an approach using only the basic flight control computer laws and basic navaids? In other words, hit the outer marker or whatever the final approach fix and simply use the stick and power to fly the "bug", or even descend at a reasonable angle/descent rate until reaching minima?

I understand all the automation and such to "help" the pilot in command. OTOH, we're not talking about the single-seat planes I flew for many hours ( and they had cosmic nav gear and such, and the last one was the first fly-by-wire jet). The heavies seem to have someone else in the other seat to "help". What is going on with crew coordination and monitoring by the "crew" of the guy that has the ultimate responsibility?

I am becoming scared, and I believe I have the background and right to do so.

Gums sends ....

HundredPercentPlease

25th May 2010, 21:36

Gums,

You can just turn the automatics off and hand fly it if you want to.

Least accurate and highest risk method though.

In increasing order of accuracy (and reducing workload and risk):

Hand fly using raw data. Cigar in mouth and amusing hat donned. It is mandatory to remind the white faced FO on the way down that you have 38,000 hours and nothing beats experience.
Hand fly using flight directors programmed with something useful. Pointless.
Automatics in conventional modes (hdg and v/s). Like a basic 737.
Automatics using track and FPA mode.
Automatics using NAV (FMC lateral) and FPA mode.
Automatics following a pre-programmed and checked database lateral and vertical flight path.

All though require monitoring of the raw data - because it is still an NDB approach. Just some methods are more accurate than others.

SLFinAZ

25th May 2010, 22:15

ELAC

26th May 2010, 00:12

Hand fly using raw data. Cigar in mouth and John Wayne hat on. It is mandatory to remind the white faced FO on the way down that this is what you signed up for when you decided to fly and 38,000 hours later you still need to respect the airplane and the process and not take any shortcuts. You always fly the plane and never let it fly you...

Most accurate and lowest risk method, after all the plane will do exactly what the pilot commands.

If you believe that, I have swamp land in Florida and a bridge in Brooklyn that you might be interested in.

What amuses me in all these "perils of automatics" diatribes is that the posters never actually get around to any real quantification or analysis of the relative risks, nor do they reference the substantially lower accident rate associated with today's operations versus those of yesteryear. Automatics do bring with them their own risks, lowered manual proficiency and automation complacency being two of them. Those risks are, however, several degrees of magnitude lower in terms of their prevelance as causal factors than the risks that automation was intended to address.

With respect to this accident, up until Sitting Bull's recent post there has been nothing much to really go on but suppositions that were unanchored to any established facts,. And though some have done valiant work trying to find facts, the contributions of the "grumbling grandpas" and the "low skill libyan" contingent have really dragged the thread down. There may ultimately be some truth to both assertions, but so far there are no known facts that suggest either, and it just gets tiresome reading the same old dogs banging the same old drums again and again.

If we accept the following as reported by Sitting Bull:

-AAW771 was cleared for and executing the NDB 09 approach
-they did not report any problems nor did they request any medical assistance
-they announced and initiated a go-around at low level (tower radar and Alitalia TCAS)
-according to the official statement of the Alitalia crew that witnessed the crash, AAW771 descended out of the low clouds nose down, wings level and in one piece
-after violently hitting nose first it disintegrated with the tail separating and tumbling over

Then this, along with some previously suggested information regarding the crew's experience on type produces a plausible hypothesis that was suggested earlier on: somatogravic illusion.

The A330 (like many other heavy twins) has very substantial excess power available when operating on both engines at typical landing weights. When the pilot selects TOGA all of that power is brought to bear, causing both a pitch up moment and rapidly accelerating airspeed. Managing the change in attitude and airspeed, especially at lighter weights is more of a challenge (and much less practiced) than doing the same on one engine.

The significant acceleration involved can create a very convincing sensation of a more rapid than desired pitch up that can be quite disturbing for a pilot unprepared for it. This would be especially the case for a pilot with limited experience on the A330 but lengthy experience with 4 engined or lower powered twin engined aircraft.

Per the Alitalia crew's observations (TCAS) it would appear that a normal go-around (the crew called out that they were going around as opposed to a terrain avoidance manouever case which wouldn't likely have been called out) had been positively commenced and that the aircraft had begun to climb only to be observed descending with a substantial nose down attitude moments later.

The simplest explanation for how the aircraft got from A (climbing, hence nose up) to B (descending with nose down) is that either the pilot or the autopilot introduced a very large scale nose down pitch input shortly after commencing the go-around. It is not impossible that the source of the input was the autopilot, but it is much more likely that the source of the input will be found to be a pilot suffering from and responding to a somatogravic illusion during the go-around. This would also explain the degree of destruction of the airframe which is consistent with a high G impact (nose down attitude + TOGA = high vertical rate).

If this should all prove to be the case, the sad irony is that some of the old dogs and grumbling grandpas will have got it entirely wrong. The airplane may well have crashed, not because the crew relied on the automation too much, but rather because at the critical moment, they relied on the automation too little.

The somatogravic illusion has been around as long as there have been airplanes in the sky and its claimed victims from both old fashioned steam driven aircraft and now new-fangled electric jets. The problem is that no matter how big you make the primary flight display (ADI), how capable the autopilot, or even how often you hand fly your approaches all the way from TOD, you can't prevent the pilot from experiencing the illusion, you can only train him in how to recognize it and how to respond to it ... including by using an autopilot that does not experience the illusion in the first place.

ELAC

SLFinAZ

26th May 2010, 01:08

I believe that any pilot incapable of safely and confidently handflying a commercial jet under extreme and challenging circumstances (USAIR 1549) should not be in command of said aircraft. The swampland has already been purchased by all of those who mistakenly believe a complex and unforgiving system can be engineered to the lowest common denominator.

Sadly the bill is going to continue to be paid by those unlucky enough to be in the wrong place at the wrong time for a decade or more to come. The 1st time this argument ever occurred was in 1959 at the beginning of project Mercury. I've got no issues with automation but I have a question for all of you advocates...

How many of you would sit in the right seat with the lowest time Captain (A320 Qualified) from any random airline and put your fate in his hands under those exact circumstances. We are repeatedly seeing pilots apparently incapable of basic unusual attitude recovery or basic proficiency in cockpit scan and basic IFR procedures...just looking here at this board right now not one of the three current tragedies can have happened (based on what we currently know) with the combination of proper scan and procedures...yet all of you are ignoring the basic fact that all to often the PF isn't even the PM and the other guy in the pointy end might as well be in the back with me...

nojwod

26th May 2010, 01:52

I believe that anyone (especially SLF), who has not been at the pointy end and experienced the disorientation of the competing demands of the senses in marginal visual conditions, especially when combined with fatigue (and who knows what other variables at any particular moment), and still espouses the merits of hand-flying, has no real concept of the incredible range of variables that can be encountered, not all of which can ever be covered in even the most exhaustive pilot training.

I remember one of the great lessons in disorientation that I read years ago. The pilot telling the story was flying formation with another Tiger Moth in late afternoon haze with little or no reference horizon, just the orb of the sun off to one side. As he flew along in straight and level flight he was amazed to see the other Tiger Moth perform a slow and gentle barrel roll around his aircraft and then resume level flight as if nothing had happened.

After landing he raised the topic of the strange maneuver with the other pilot who told him in no uncertain terms that it was in fact he who had rolled around the other aircraft. Both pilots were adamant they had continued flying straight and level and it was the other aircraft that had performed the unexpected maneuver.

EMIT

26th May 2010, 02:49

In the hand flying versus automation debate - in my opinion it is not so much the automation that has improved safety, it is the integrated display of information.
"I love the magenta line" in the sense that the navigation display gives in one glance a complete picture where I am in relation to (objects/places in) the real world - that's a lot easier than puzzling it all together from a set of needles and dials giving directions and distances towards beacons.
At the same time, common sense is required to deal e.g. with faulty waypoint sequencing, such as often occurs during close-in vectoring on approach. If that common sense is missing, than you are a slave, rather than a lover, of the magenta line.

The somatographic illusion - yes, it exists. Should you be able to counter it, well with a big artificial horizon in front of you and a simple, basically wings level attitude as a start point, yeah, one should be capable to deal with that one. It takes discipline, that's for sure and perhaps a bit of hands-on experience (... perhaps a little handflying, and not only in 100 nm vis, CAVOK weather ...)

Automation, be it Airbus or Boeing, beautiful, makes life easy, but still, if the machine doesn't perform as you want, two clicks and you are back in charge.

Edit for typo.

gums

26th May 2010, 03:04

Salute!

TNX for the list of priorities, 100%.

I don't have multi-dozens of thousand hours. I was only a lite puke and we had many more landings than hours. Sorry, but that's the best I was offered and I did it.

I flew "coupled" autopilot ILS approaches in the VooDoo back in the 60's, and it was neat. OTOH, I had a paddle switch on the stick that disconnected everything except the basic control laws the jet had. So if I saw something that didn't look right I could squeeze the paddle and level, land or go around ( TOGA mode, but no computers).

I appreciate all the aids that the current folks have. Make no mistake. I debated use of the HUD with many folks that were the "cigar-chomping" mossbacks that claimed you had to fly the approach using the steam gauges. I could do that. I also enjoyed cross-checking the steam gauges with the fancy HUD display of the approach angles and such. No autopilot connect for the SLUF and the Viper.

I just worry about the new folks that might be tempted to rely too much on the automation. I am worried about basic flying skills that can be degraded by using all the gizmo's so much that basic airmanship will come into question when a crash occurs. Should not be that way. Sully proved you can fly the Airbus very well with virtually zero assistance from all the avionic connections. So the plane must have decent basic flight control laws. It's all the other connections with the flight controls that bugs me.

My last fear is that the "other guy/gal" might not speak up when the pilot-in-command is doing something screwy. My NWA buddy has talked about a philosophy of using both folks at the pointy end to cross-check each other and speak up when something didn't look right. My only experience in two-seaters was a navigator in the back seat that would calmly mention I was "pressing". Heeded his advice a few times and am still here to relate war stories.

I'll sit back now and look for the CVR and DFR to figure this one out.

Thanks to all the current professional folks here that fly these new planes and have contributed to this thread.

Gums sends ...

PA-28-180

26th May 2010, 03:08

"How did the nose eradicate the electrical poles (if it was the nose)?; How did the electrical wire ended in the tail cone?"

First, let me also give my thanks for CSAR for all his 'on the ground' reports!
Now...forgive me for posting this, however I thought it might have some relevance to the above questions....

During my primary training (about 300 years ago!), I watched a NASA video on wake turbulence. They had set up a series of poles at the departure end of a runway and then had a 747 take off. The film showed the poles begin swaying more and more wildly, until finally several of them ripped out of the ground. HOWEVER, they didn't go very far....simply popped out of the ground and fell over.
So...since the poles were only about 3-4 meters in height (as per previous posts)...could it have been wake vortex as the aircraft flew over that damaged the poles? Then, perhaps, 'dragged' the wires behind the aircraft in it's wake?
Just curious....this video had a BIG impact on me during my initial training and I've never forgotten it.

physicus

26th May 2010, 03:42

I really don't understand this automation debate... look up the accident statistics. ~ 70% of all aviation accidents in RPT resulting in death or serious injury are caused by operator error (pilots) and not by automation flaws. There is no evil autopilot that flys you into the mountainside. Unless you told it to do so.

Thousands of hours of single pilot IFR have taught me a few lessons. One of them is to always rely on, and crosscheck, the instruments. I've had a few spectacular instrument failures in IMC that could easily have resulted in my demise (hence categorised as spectacular), but never did all of the instruments cheat on me. So, before pushing on the stick like mad you might want to take a glance at that PFD... then at the standby cluster if the data you see still doesn't make sense. Then make an informed choice, and fly out of it. I'm not too familiar with MCC, but isn't the idea that the PNF monitors instruments and takes care of comms? I would hope that at least one of the two doesn't fall for somatographic illusion, and can snap the other one out of it. Unless, of course:

- they busted MDA knowingly, and not by just a few feet.
- frightened themselves when the TCAS RA went off (what did that tell them to do, possibly: Don't climb? Maintain vertical speed?)
- they now know that they will get caught busting the minimum.
- initiated the G/A
- were so low below the minimum that a piloting error resulted in the photographic evidence we have all seen.

It would be really useful if they published a decent subset of DFDR parameters to the public so we can make a more educated assessment of what was going on.

jcjeant

26th May 2010, 05:06

Hi,

I really don't understand this automation debateI understand very well this debate.
The automation is the third crew member (as usually today commercial jets are provided so far with two humans pilots)
This third crew member is the most busy of the 3 during the flight operations.
So .. not astonished this third crew member can be also implicated in case of problems.

JoeMo

26th May 2010, 05:42

Hi C-SAR
About the poles.
Here are 2 pics of the poles before the crash that I found.
You will see that they are exactly in line with and on the crash site.
The lines run all the way past the little tower that is at the corner of the runway and even run to past where the wings are.
Note that the 2nd pole is a 4-type-box, the others are single.
Look at 4:00 min of YouTube - Landing at Tripoli International Airport, Libya (http://www.youtube.com/watch?v=1srEE7qq9jw)

pic1
http://i50.tinypic.com/2ufdpag.jpg

pic2
http://i47.tinypic.com/2zxrvgz.jpg

pic3 another 4-pole-box on the right side of the right wing just outside of the fence
http://i46.tinypic.com/2196yk7.jpg

pic4 Note that the pole and tower have no damage, while lots of havy debris are located in that area. Most is just in front of the trees and others against the fence. Also that the wings have gone over the pole.
http://i46.tinypic.com/200s4r5.jpg

C-SAR, thanks for your help
this was my first post here

JoeMo

26th May 2010, 07:21

Looks like some things have been over looked.
Have a good look at these pics that I have seen.
Some are from the day after NOVA stream.
Here you see that the first large part of debris is a large front part from the fuselarge that is located before the tail cone. It is a part of the right side, juist after the cockpit with the company name. This part is located just before the little house that stand before the mosque .

pic1Day2 FirstLargePiece1
http://i45.tinypic.com/14azvgy.jpg

pic2 Day2
http://i45.tinypic.com/nxmik0.jpg
pic3 Day 1
http://i50.tinypic.com/2960e9.jpg
pic4 Day 1 later on
http://i49.tinypic.com/10s7u48.jpg

PBL

26th May 2010, 08:26

It may be worth reminding discussants of two things.

First, I see no reason to suppose that any FDR or CVR data will be made public. Neither would I necessarily expect that the ICAO-required final report will be made public. Let's see first if the required 30-day report is made public.

Second, participants in any of the investigations (Annex 13, or insurer's, or ...) will be under non-disclosure and are very unlikely to participate in any way in public discussion if they value their jobs and life savings. Missives from anyone claiming here that they *know* what went on can most wisely be read with this in mind.

Finally, anyone in favor of the tail-struck-first scenario could please explain the puzzle I posed a few days ago, namely how one can get an AoA of 16°+descent path angle on an A330 at approach-like speeds. So far, no one has tried.

PBL

aterpster

26th May 2010, 09:29

pbl:
It may be worth reminding discussants of two things.

First, I see no reason to suppose that any FDR or CVR data will be made public. Neither would I necessarily expect that the ICAO-required final report will be made public. Let's see first if the required 30-day report is made public.

Second, participants in any of the investigations (Annex 13, or insurer's, or ...) will be under non-disclosure and are very unlikely to participate in any way in public discussion if they value their jobs and life savings. Missives from anyone claiming here that they *know* what went on can most wisely be read with this in mind.

Let's hope you're wrong, but I suspect the odds are very high that you are right, particularly in view of the history of the host country (some contrary posts on this forum notwithstanding) and further than the air carrier is carrying the host country flag.

If that is indeed the end result, then all responsible carriers best avoid operating into that country.

BOAC

26th May 2010, 09:41

Excellent post, JoeMo thank you. That probably defines the crash sequence neatly and fits with the Alitalia report.

takata

26th May 2010, 09:52

Hello,
Looks like some things have been over looked.
Have a good look at these pics that I have seen.
Some are from the day after NOVA stream.
Here you see that the first large part of debris is a large front part from the fuselarge that is located before the tail cone. It is a part of the right side, juist after the cockpit with the company name. This part is located just before the little house that stand before the mosque .

Certainly not there.
Pic3 and Pic4 are not the same piece of wreckage as the front fuselage piece shown in your Pic1 and Pic2. Look at tail orientation and you'll see that this piece is much closer to the airport fences (where another house is visible) and certainly not before the mosque, while the white wreckage shown in Pic3 and Pic4 is from rear fuselage near the tailcone. I already posted something about that several pages back in this thread.
S~
Olivier

Edit: or maybe that's me who was mis-oriented!
Actually, the tail is on the other way that I believed first... you may be right JoeMo!
S~
Olivier

ELAC

26th May 2010, 10:13

I believe that any pilot incapable of safely and confidently handflying a commercial jet under extreme and challenging circumstances (USAIR 1549) should not be in command of said aircraft.

SLF, this is just blather without meaning. Your initial point was about aircraft handling and instrument flying procedures but in your next breath you are suggesting USAir 1549 as an example of the level challenge that any pilot should be fit for without recognizing that the challenge of that situation had nothing to do with instrument flying skills, little to do with actual aircraft handling skill and a dead nuts zero to do with automation. The challenge there was in decision making. That's a talent that's entirely independent of equipment, though you can be sure that when those rare moments arise any pilot with brains is going be thankful for whatever the airplane can do to help him assess the situation and find the decision with greatest possibility of a safe outcome (which like for 1549 is not necessarily a certainty - you can be sure that at 200' Sully was wondering "What comes next?")

The swampland has already been purchased by all of those who mistakenly believe a complex and unforgiving system can be engineered to the lowest common denominator.

Sadly the bill is going to continue to be paid by those unlucky enough to be in the wrong place at the wrong time for a decade or more to come. The 1st time this argument ever occurred was in 1959 at the beginning of project Mercury.

More blather. What are you complaining about ... that the manufacturers are mistaken in trying to improve its product to make them easier and safer to use, or that the airlines have dropped their standards so much that the "lowest common denominator" who are now flying aircraft do so incompetently, and yet also with fewer accidents than their predecessors?

We are repeatedly seeing pilots apparently incapable of basic unusual attitude recovery or basic proficiency in cockpit scan and basic IFR procedures...just looking here at this board right now not one of the three current tragedies can have happened (based on what we currently know) with the combination of proper scan and procedures...yet all of you are ignoring the basic fact that all to often the PF isn't even the PM and the other guy in the pointy end might as well be in the back with me...

Are we now? Guess you opted for the incompetent pilot explanation.

Actually, based on what we know so far about the three current tragedies (Polish Air force, Afriqiyah & Air India Express) there is nothing to suggest that a lack of proficiency with "basic unusual attitude recovery or basic proficiency in cockpit scan and basic IFR procedures" had anything to do with any of them.

Information available so far suggests that the PAF TU-154M commander knew very well that he was descending below the minimums for the approach he was conducting. If true that would be an error in decision making that no amount of handling or IFR procedures proficiency could prevent.

Likewise, the Air India Express accident is the result of a runway over-run, the common causes for which are excessive altitude at the threshold or excessive speed at touchdown resulting a long landing, or a degradation in runway or aircraft conditions impeding normal braking ability. The facts to support which it is in this case aren't in, but none of the alternatives involves a failure in proficiency resulting from an over reliance on automation or instrument flying skill. When the facts are known, however, the likliehood is that we will be looking again at a decision making error as opposed to a handling error.

And for the accident that this thread is about, up to this point there has not been a single shred of evidence that points to either automation itself, or piloting skills that have been atrophied by a reliance on automation as a causal factor. So far we know precious little, but what little we do know (allowing that Sitting Bull's info is accurate) suggests that the aircraft was under control until some point just after it initiated a go-around and that it climbed then reversed and descended very quickly. Why is not known, but the fact that the aircraft was wings level is telling. Unintentional losses of control resulting from poor instrument scan almost always result in a departure first in roll followed by pitch, which if it had happened here would have resulted in the aircraft impacting in a banked attitude, not straight ahead nose first as observed by Alitalia.

Pending other evidence being adduced, I'd suggest that an explanation fitting these few facts is a somatogravic illusion, the response to which may have been sufficiently abrupt to place the aircraft into an unrecoverable attitude even if a recovery was attempted. If it was this, there again neither automation nor automation dependency will have played a part. The result would be the same regardless of the size of the dials (they don't get much better than the A330's anyhow) or the qualities of the autopilot.

I suppose you could argue that succumbing to a somatogravic illusion reflects a lack of instrument flying proficiency, but that's a bit facile as it doesn't consider the difficulty of replicating such conditions in a training or line environment, the fact that all the hand flown approaches in the world won't provide you with the same experience if they result (as 99% do) in a landing, or the fact that in the right conditions the illusion can be very, very powerful indeed.

In this last quality it might be comparable to the illusion that reading enough of what's posted on PPRuNe can make some who describe themselves as SLF sitting in the back believe that they are qualified to make such sweeping statements as "We are repeatedly seeing pilots apparently incapable of basic unusual attitude recovery or basic proficiency in cockpit scan and basic IFR procedures."

Truly amazing.

Now can we start sticking to facts known or genuinely relevant operating experience as the basis for future conjecture?

ELAC

PBL

26th May 2010, 10:39

aterpster,

let me make clear that my comments were general, and do not refer in particular to the host country.

First, most countries which are members of ICAO do not publish details of investigations publically, in particular those with more limited resouces. The NTSBs of this world are the exception, not the rule. (Although the global trend towards publication is to be welcomed.)

Second, all investigators, everywhere, operate under non-disclosure agreements.

So your comment
If that is indeed the end result, then all responsible carriers best avoid operating into that country.
goes way beyond what I was trying to say. I don't think you can conclude anything about the host country from what I was saying, except that it's not the U.S., France, Britain, Germany or Australia.

PBL

SaturnV

26th May 2010, 10:49

On the Alitalia observations, I don't believe there has been an official statement released on what they saw. In fact, reading back through this thread, there seem to be conflicting narratives about the sequence as they supposedly observed it.

There is no plot that I have seen of the position and orientation of the Alitalia plane at the time the crew observed the impact, nor has there been any calculation of the distance between the Alitalia plane and the first pole knocked down, nor a correlation of that distance with the visibility at the time.

Neptunus Rex

26th May 2010, 10:55

Whatever the host country chooses to reveal, or hide, Airbus Industrie has a huge vested interest in the outcome. You may be sure that they will do everything possible to protect their product and will make appropriate disclosure.

Sitting Bull

26th May 2010, 11:16

dear SaturnV and PBL

-the Alitalia crew made an official statement to the relevant authorities and it has not been made public
-no matter what their position was (actually exactly towards the approaching A330), they still remain the only people that witnessed the crash
-as stated in an earlier post: whatever happened before the A330 came into their view remains to be retrieved from the DFDR and the CVR (in progress)

if you allow me to offer my personal opinion on the suggestions that Libya might not release the accident report: I had the possibility to speak to several of the Libyans in charge of the investigation and I did not get the feeling that they will try to keep the results a secret. As a matter of fact they have conducted the investigation very professionally so far

RetiredF4

26th May 2010, 11:24

ELAC
If this should all prove to be the case, the sad irony is that some of the old dogs and grumbling grandpas will have got it entirely wrong. The airplane may well have crashed, not because the crew relied on the automation too much, but rather because at the critical moment, they relied on the automation too little.

I,m not fishing for compliments, however an "old dog and grumbling grandpa" and even a retired one (also my brain is still working) had this possible chain of events mentioned long ago, fact being with little attention of the younger "modern" pilots. I might have used the incorrect wording though.
One Question being, why they did not rely on automation?

post 357 (http://ww.pprune.org/5693763-post357.html)
Post 418 (http://www.pprune.org/rumours-news/414936-afriqiyah-airbus-330-crash-post5695535.html#post5695535)

The question, wether the modern pilot used to max extent of automation is fully capable of taking over the workload of the computers (caused by deliberate act or by malfunction) concerning thinking, planing and handling (like the "old dogs" had to do due to lack of reliable automation) is legal. And nobody asking this question is wishing back the old days, but remembers his own flying skills.

I´m not suggesting yet that this has anything to do with the cause and outcome of this tragic accident.

franzl

arc-en-ciel

26th May 2010, 12:07

Hi guys,
It is rather "easy" to **** up a go-around and hit the ground with high energy.

Step one : Do not set the Thurst levers in the TOGA detent : (this has happened very recently to an A320 of JetBlue and Air France)

Step two : Set the Auto-Pilot back On (As an AF A320 in Sept 2009 at CDG)

Result : The SRS mode will not be triggered and aircraft will still be in the approach mode, and consequently descend with engines spooling up, then in IMC if you don't read your FMA (like Jetblue and AF) the somographic illusion occurs... and you have very few seconds to react when you see the ground coming when breaking of the cloud base (the AF had a ceiling of 300ft as well, and they stopped the descend at 70 ft if I remember well, but this was an A320, easier may be to arrest the descend).

Then may be a sort of more or less "flat" ground contact. And bearing in mind that the Alitalia aircraft was at least at a 1000M from the crash scene, in dawn light and reduced visibility, they may not have a very clear view of the final aircraft attitude at ground contact.

SLFinAZ

26th May 2010, 12:25

ELAC,

I'm not trying to downplay the benefits of automation in any way, just the total apparent reliance that is becoming more and more evident. As automation takes on more and more of the work load it's readily apparent that the system is both to complex for at least a portion of the user base to manage under stress and that it's use is compromising basic skills to some significant measure.

Instead of automation leading to a net increase what we're seeing is an increase in the capability of one segment (automation) leading to the degradation of another (actual hand flying capabilities).

We're at a point where its possible for a pilot to log 80 flight hours and have less then 2 or 3 total hours (if that) actually hand flying a plane. Where I disagree with you in your interpretation of "decision making". That is exactly what hand flying is, making decisions. The alternative is observing a computer automatically make those minute corrections for you. After all isn't that what software does? It takes the raw data stream and applies a set of predetermined formula's and acts based on the resulting calculations.

If in fact AF447 was an upset at altitude due to the automation reaching a point it kicked out (pure speculation) then would not the lack of hand flying experience at altitude have severely hampered any attempts at recovery by the pilot flying since he had no real experience under such conditions.

This further compounded by a confidence in the automation that encouraged an altitude selection beyond what a hand flying pilot would be comfortable maintaining given the very narrow boundaries?

At the end of the day how can a competent pilot rely on automation "to little" . Nothing can be safer (and yes thats just my opinion) then actually hand flying an airplane. Otherwise lets just equip em all with a little "autosave" box...

Automation in place of training and proficiency is going to cause significant issues...just one persons opinion...
In event of emergency break glass, pull lever and sit back and enjoy the ride

SaturnV

26th May 2010, 12:44

Sitting Bull and C-SAR, thanks for the information you've been sharing.

A post that I was referencing was this one by a Dutch reporter, who never received a post in reply in this forum. The reporter says that he was in email contact with the pilot of the Alitalia flight. Going from Italian to Dutch to English can leave a lot behind in translation, but I would assume that "backangle" means a tail down, nose up configuration.

I'm a reporter of a big Dutch newspaper and had brief contact through email with the pilot of AlItalia who was an eyewitness of the crash in Tripoli. He posted a message on what he saw on the forum of anpac.it. The press-officer of ANPAC told me one brief passage of his post: the plain had far too much speed and was touching the ground with a backangle of more than 20 degrees. A Dutch flight-expert told me that this indicates that the pilot must have been disorientated and that he tried to pull up the plane in the last seconds.

My question: are there any Italian pilots here who can login to the (closed) forum on the website anpac.it? If so, can anyone send me the passage this Italian pilot wrote? As you might know the majority of the victims is Dutch and relatives of them are very interested in everey detail there is to tell. Please leave your message here or send it to: ivar.penris at ad.nl.

http://www.pprune.org/5700833-post644.html

(And please note that post numbers can change over time.)

lomapaseo

26th May 2010, 12:57

A large degree of caution is urged in adopting photos, on scene interpretations, eye witness reports from aviation professionals and lastly DFDR raw data as conclusive affirmation that your pet theory about the chain of events is correct.

In an investigation like this many conflicts arise (nose down vs nose up impacts, etc.) that take time to sort out by matching sources of information with a degree of analysis (aircraft performance laws etc.)

The individual casual observers, like ourselves do not have the resources to resolve these conflicts, so while we may have experienced based opinions we have little credibility to conclude a chain beyond a single fact.

Centaurus

26th May 2010, 13:09

Pending other evidence being adduced, I'd suggest that an explanation fitting these few facts is a somatogravic illusion, the response to which sufficiently abrupt to place the aircraft into an unrecoverable attitude even if a recovery was attempted.

While I understand the medical side of so called somatogravic illusion, I cannot understand why a veritable stream of airliners are not crashing on take off after lift off (very marked acceleration) or from the thousands of IMC go-arounds that must take place in any one period throughout the world. In all cases one would think that the pilots would all be affected by the acceleration forces involved with speed increase after lift off or go-around.

Catapulting from an aircraft carrier at night or IMC would surely be the most dangerous risk from SI yet rarely do we hear of these aircraft crashing into the ocean after take off. Having flown early piston engine fighters (Mustang) as a young man with only 200 hours in my log book I don't ever recall experiencing SI at take off at night in that aircraft and in fact I have never experienced this phenomenon in my entire 60 year career as a pilot and that includes jet airliners.

If SI is as insidious and potentially dangerous as advertised in flight safety circles, it doesn't explain why thousands of pilots are apparently unaffected and therefore don't crash when faced with IMC take offs and go-arounds

RetiredF4

26th May 2010, 13:50

Having flown fast jet-fighters (F-4 Phantom II) i´ve expierienced it myself. Think about formation flying in IMC, the wingtip (not the fuselage) of the lead aircraft being the only available reference. The fact that i´m still living may prove in my case, that i could handle it like most pilots do.

When can it happen and why doesn´t it necessarily lead to an accident, like you are trying to argue? Because a human being has more then one sense giving information to the equilibrium and the sensory illusions asociated with limited availability of those informations should be well known to any pilot with a valid Instrument rating. So you stick to your instruments and wont get any trouble.

Therefore being in IMC or Night, on takeoff or doing a goaround while using the instruments as reference wont lead to those symptoms, because your brain is able to ovverride the wrong information. The more you are prepared for it, the less it will happen.

But being in a approach in VMC and suddenly and unexpectedly loosing sight of RWY and horizon, being forced to commence an unplanned goaround with lot of acceleration (which is even higher if the climb is not initiated immediately), calls for those sensory illusions. And even then you are not alone in the place and with qualified help it will work out fine.

But there are those days.........

However, as mentioned by others, its only one way to fly into the ground during a goaround, and we will hear later what the real cause was.

franzl

TowerDog

26th May 2010, 14:04

If SI is as insidious and potentially dangerous as advertised in flight safety circles, it doesn't explain why thousands of pilots are apparently unaffected and therefore don't crash when faced with IMC take offs and go-arounds

Agree, it has never affected me in 32 years of flying.
If indeed it was a big deal there would be wrecks scattered around the country side by the thousands..:sad:

A bit of basic instrument skills should mitigate any S.I. and S.I. should not be a reason or an excuse to fly an operable craft into the ground.

Try a good scan instead.

aterpster

26th May 2010, 14:18

pbl:
Second, all investigators, everywhere, operate under non-disclosure agreements.

But, that is based on the premise that the aviation investigative authority for the host state will release the findings when the investigation, gathering of facts, and analysis and conclusions are complete. (i.e., let's speak with one voice, and not take untoward advantage of priviledged status until the investigation and related processes are completed.)

As someone else state, and I will word it differently, Airbus would be a corporate fool to not release the findings if Libya does not.

Finally, it is inconveivable to me that Libya does not have the resources to publish an accident report.

jcjeant

26th May 2010, 14:29

GarageYears

26th May 2010, 14:35

Agree, it has never affected me in 32 years of flying.
If indeed it was a big deal there would be wrecks scattered around the country side by the thousands..http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/puppy_dog_eyes.gif

A bit of basic instrument skills should mitigate any S.I. and S.I. should not be a reason or an excuse to fly an operable craft into the ground.

Isn't that a rather gung-ho position to take? For one there have been SI related crashes and the causes are well understood in medical circles. The human brain is a highly interconnected, particularly when it comes to ears-and-eyes. Our sense of balance is tuned to our normal physical function - walking, running, climbing, etc. Believe it or not humans have only been hurling ourselves around in the sky for what, a little over 100 years. So our normal senses are not designed for what can happen in an aircraft. I have seen people fall over in simulators (particularly with the motion turned off, and the visual on) simply because of SI.

SI is insidious since by the time you are aware of it, it may well be too late. To dismiss this at this point seems over-zealous.

Obviously most pilots, following normal procedures, instrument scans, etc, are not going to succumb, but that does not mean it doesn't happen - particularly when something unexpected occurs. In this case something appears to have initiated the crew to attempt a go-around, so something unexpected occurred - we don't know what - perhaps visibility. However that is exactly when an SI situation might be expected to occur.

It does frustrate me - just because it hasn't happened to you (yet) doesn't mean it never will, or won't happen to someone else. Evolution is something that takes thousands of years - or are you somehow different?

- GY

ELAC

26th May 2010, 14:40

I,m not fishing for compliments, however an "old dog and grumbling grandpa" and even a retired one (also my brain is still working) had this possible chain of events mentioned long ago, fact being with little attention of the younger "modern" pilots. I might have used the incorrect wording though.
One Question being, why they did not rely on automation?

Hi franzl,

Yes, I think yourself, PJ2 and perhaps others mentioned the possibility of somatogravic illusion earlier on and refrenced the GF crash. It had crossed my mind too as I've not been sold on the tail first contact hypotheses, but until Sitting Bull mentioned the info reported by the Alitalia crew there was nothing that particularly pointed in that direction. Now, while hardly the only possibility, there is a "fit" between facts reported by competent observers and the results of a somatogravic illusion response, so I think it's worth pointing that out, particularly in response to suggestions that the cause is rooted in automation or approach flying skill degradation.

Why they didn't rely on automation? If, and it is an "if" somatogravic illusion is the culprit I think that the answers would be both the powerful effect that it can have along with a lack of specific training to identify the potential for it to occur and the best piloting responses if it appears to be occurring.

The question, wether the modern pilot used to max extent of automation is fully capable of taking over the workload of the computers (caused by deliberate act or by malfunction) concerning thinking, planing and handling (like the "old dogs" had to do due to lack of reliable automation) is legal. And nobody asking this question is wishing back the old days, but remembers his own flying skills.

That in itself is a totally valid question. In the end an airplane is an instrument and the proficient pilot needs to know and be capable in all aspects of its operation. It is fair to have concern over possible degradation of hand flying skills without conflating the value of those skills with a perception that safety would be improved by a return to a greater emphasis on hand flying and a reduction in the levels of automation available or commonly used. The two concepts are not corollary and joining the two, in my opinion creates a misperception about what needs improvement and what provides the greater overall benefit to flight safety.

Tschüss!

ELAC

Belgique

26th May 2010, 14:57

Accident Report
http://tsb.gc.ca/eng/rapports-reports/aviation/2001/a01c0236/a01c0236.pdf
The loss of visual references as the aircraft accelerated along the runway and past the lights of the community were ideal for the onset of somatogravic illusion in the pilot flying. Even 7 seconds prior to impact, the captain believed that he was climbing to 1000 feet above ground level. The captain’s performance was consistent with his being unable to distinguish the imposed acceleration as the aircraft speed increased from that of gravity and, although he probably thought the aircraft was climbing, it was not.
The first officer may also have been influenced by the somatogravic illusion. During the 30 seconds of the missed approach, his tasks were to react to the captain’s commands and to monitor the instruments. Apparently the first officer did not observe anything remarkable or he would have alerted the captain that the aircraft was not climbing.
It is possible that he was distracted by the sudden sound of the NDB identifiers just after the missed approach was initiated. The NDB receiver was turned off just prior to impact, and since the control head is on the first officer’s side of the cockpit, it was likely he who turned the NDB off. Given the short duration of the overshoot and the tasks that the first officer was performing, it is probable that he had a false perception that the aircraft was climbing.
Even though the conditions were present for the crew to be affected by somatogravic illusions, these illusions could have been overcome by at least one of the crew. During the visual approach, the pilots were able to fly with visual reference to the surface. However, pilots are required to transition to instruments when entering, or about to enter, weather or environmental conditions where visual flight conditions do not prevail, as was the case when
the overshoot was initiated. Had this transition been made, the fact that the aircraft was not climbing would have been evident.
The company SOPs for the missed approach was less stringent than those for the company’s training school. There was no stated requirement to use instruments during a missed approach nor a requirement to identify two positive rates of climb. The use of these two techniques would be a stronger defence against the possibility of somatogravic illusion and loss of situational awareness.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.
High acceleration during take-off and initial climb can cause an illusion of increasing pitch. Somatogravic illusion (aka the "pitch-up illusion") is an erroneous sensation of pitch (rotation in the vertical plane) caused by linear acceleration. Under normal conditions this sensation can be recognized and corrected by visual means; however, when a take-off (or go-round in particular) is being made on a very dark night, and toward an area that provides few visual references, this illusion will remain a powerful influence. A pilot's normal response to this pitch-up illusion is to apply forward pressure to the control column, and to reduce the aircraft's angle of climb. As the pilot unloads, so the acceleration forwards is reinforced by the negative g and so the illusion is thus progressively (and rapidly) enhanced.
.
Air Afriqiyah A330
Sudden loss of forward vision due to sunrise glare, accompanied by a fair expectation of regaining it momentarily, would deter a pilot from getting back on the clocks, particularly if he knew that he was quite close to the ground.
Sudden unexpected loss of forward vision in conditions of sunrise and sunset landings is not at all uncommon. Fly long enough and it will happen to you. If accompanied by an attempt to go round, then the light-weight aircraft's rapid acceleration during mandatory TOGA can suddenly become a player. The fact that both pilots can experience the phenomenon simultaneously (see above and GF072 Report) is also a factor. Consider also that if a non-handling captain is looking outside for visual cues when he experiences this overpowering illusion, he may well intervene and take drastic action - such as stuffing the nose down. At ow altitude an unrecoverable attitude is always likely to result.
.
Dark Night Takeoffs (http://aeromedical.org/Articles/dnt.html)

http://www.pprune.org/tech-log/9199-somatogravic-illusion.html

Untitled Document (http://bankslab.berkeley.edu/Projects/SGIllusion.html)

Transportation Safety Board of Canada - AVIATION REPORTS - 1996 - A96C0002 (http://tsb.gc.ca/eng/rapports-reports/aviation/1996/a96c0002/a96c0002.asp)

Untitled Document (http://bankslab.berkeley.edu/Projects/linearAccelTxt.html)

http://www.pprune.org/rumours-news/4364-gulf-air-changes-since-gf072.html

Approach and landing illusions (http://aeromedical.org/Articles/a&l.html)

Untitled Document (http://bankslab.berkeley.edu/Projects/SGIllusion.html)

TowerDog

26th May 2010, 15:14

Ok, so the experts have solved the puzzle now.

Somatogravic illusion is the culprit, case closed...

It does frustrate me - just because it hasn't happened to you (yet) doesn't mean it never will, or won't happen to someone else. Evolution is something that takes thousands of years - or are you somehow different?

What frustrates you? That I have never experienced SI....? :confused:

If I did, perhaps I should hang it up.

GarageYears

26th May 2010, 15:35

What frustrates you? That I have never experienced SI....?No.... this does:

If indeed it was a big deal there would be wrecks scattered around the country side by the thousands:ugh: The implication (quite clearly) is that in your opinion SI is (at best) a non-issue (since there are evidently not thousands of wrecks).

No one said "case closed" (except you :O). However, several others have, without sensationalism ("wrecks scattered by the thousands" :D), stated that SI is something that will be considered as a possible contributor to the crash. That was all.

Take a deep breath, and realize that not everyone is the perfect pilot that you so obviously are.... :ouch:

- GY

BOAC

26th May 2010, 15:36

Somatogravic illusion - a grand expression to bandy around. I prefer to call it 'dis-orientation' or 'the leans', and I would be extremely cautious with ANY pilot with more than around 1000 hours who says he or she has 'never experienced it' at night, in cloud, in formation or in manoeuvre - it is a worrying thought that they might not have actually 'RECOGNISED' it. As said above, it is extremely common and a well-known aviation medicine topic.

Anyway, if we can now leave this topic for a while? Back to the thought-provoking post by JoeMo - even allowing for the fact that cameras do fore-shorten things, is the 'forward fuselage section' not too close to the tail section to fit the tail strike/break off tail/nosedive theory? Can anyone pinpoint its exact position along the 09 approach in the wreckage trail?

ELAC

26th May 2010, 15:41

SLF,

... the total apparent reliance that is becoming more and more evident.

It is? How so?

... it's readily apparent that the system is both to complex for at least a portion of the user base

Really? Based on what metric? It certainly can't be based on accidents as we had plenty more of those with less complex equipment. To the extent that there's an issue is it not perhaps one of MMI (Man-Machine Interface) "ergonomics" for one and adequate training for another as opposed to the concept of automation in itself?

... it's use is compromising basic skills to some significant measure.

Well, first off, what is the basic skill? Is it not the ability to take the aircraft aloft and return it to the ground safely? If so, our overall skill at doing so has increased, in large part because we use all the aircraft's systems competently, not just the yoke or stick and rudder.

...Instead of automation leading to a net increase ...

But, automation has led to a net increase in the safety of flight operations. The statistics on that are fairly indisputable. There are accidents that include automation or degraded manual skills as a causal factor, but these are far fewer than the accidents that newer technologies have helped us avoid. One telling statistic that you'll never find is a tally of all the "saves" that automation has provided us that resulted in accidents that didn't happen (and consequently you never got to read about).

...Where I disagree with you in your interpretation of "decision making". That is exactly what hand flying is, making decisions. The alternative is observing a computer automatically make those minute corrections for you.

You're not serious are you? The actual motor skills in controlling the aircraft manually are for the most part completely seperate from the decision making functions related to flying. The motor skill is simply one way of translating the decision into action. Sometimes it is the best way (gusty crosswinds and windshears come to mind), but you are doing the same thing when you use the autopilot to achieve the same result. At a guess, for most airline pilots 95% of all the decisions they will make during the course of a flight, including most of the truly critical ones, will occur with the autopilot on. If you believe that manually making those "minute corrections" is the epitomy of pilot decision making then your understanding of the nature of the job is so far removed from mine we might as well be on different planets. On that disparity I can only offer that my perception is informed by many years at the pointy end. How have you come by your conclusions?

If in fact AF447 was an upset at altitude due to the automation reaching a point it kicked out (pure speculation) then would not the lack of hand flying experience at altitude have severely hampered any attempts at recovery by the pilot flying since he had no real experience under such conditions.

This further compounded by a confidence in the automation that encouraged an altitude selection beyond what a hand flying pilot would be comfortable maintaining given the very narrow boundaries?

Pure speculation indeed. As was dealt with in the relevant thread, the altitude selection of the AF aircraft was well within the normal operating boundaries of the aircraft, and not particularly narrow at all. If that in itself was a causal factor then we should be rethinking the entire approach to flying jet aircraft above FL300. Certainly I recall many occasions of being much closer to the edge of the envelope while operating the 727, and on some instances having to hand fly it at those altitudes as well (the "rocker" a/p on old 72's not being the most reliable of beasts). The altitudes we select to fly at are not "encouraged by a confidence in automation" but rather informed by a knowledge of the aircraft's operating envelope along with an appreciation of the environmental characteristics particular to the situation.

At the end of the day how can a competent pilot rely on automation "to little". Nothing can be safer (and yes thats just my opinion) then actually hand flying an airplane. Otherwise lets just equip em all with a little "autosave" box...

Well you know what they say about opinions ...

If you actually believe without qualification that "Nothing can be safer than actually hand flying an airplane." you have absolutely no business contributing to a professional level discussion about the causes of an aircraft accident. Put simply, you lack an adequate level of appreciation of what the job entails to make an informed contribution.

Automation in place of training and proficiency is going to cause significant issues...just one persons opinion...
In event of emergency break glass, pull lever and sit back and enjoy the ride

You are right in the sense that it isn't automation that's really at issue. The question is what training and what proficiency? My guess is that you and I have fundamentally different answers.

ELAC

TowerDog

26th May 2010, 15:44

Take a deep breath, and realize that not everyone is the perfect pilot that you so obviously are....

You jumped to the wrong conclusinon there garage, I am just mr. average Joe pilot, not better or worse than the majority of us.

If a working pilot is affected by SI he or she may have a medical condition that makes them unfit to fly.

infrequentflyer789

26th May 2010, 15:58

Hi,

Surprised we not have any news of the last seconds by the survivor (a little boy )
I remember in the case of the Comores accident the girl who survived had something to tell.
The medias reported a lot about her .. and here .. silence ...
It can be valuable ... or not.

He doesn't remember anything:

France24 - Young Tripoli crash survivor says he's 'fine' and 'wants to go home' (http://www.france24.com/en/20100514-plane-crash-survivor-boy-says-hes-fine-wants-go-home-dutch-netherlands-libya)

He's only 9 - the girl was a teenager. Fair bit of difference.

Lemurian

26th May 2010, 16:00

I love those people who claim never felt disorientation, vertigo, somatographic illusions, visual illusions...etc...
...and conveniently forgot that they've spent their careers in simulators being happily exposed to somatographic illusions, visual illusions, vertigo and disorientation !

Sheesh !
What is a simulator if not the only place where your inner ear sensors are aligned with a virtual visual position ?

Liars and cheats all ! ( hairy balls included)

armchairpilot94116

26th May 2010, 16:03

Any chance keeping your eyes on the instruments (and trusting them) will help here? The Ci 006 team flying the 747SP in their famous dive lost awareness while in cloud and believed it wasn't possible they were upside down and that something must've been wrong with the instruments .

China Airlines Flight 006 - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/China_Airlines_Flight_006)

ELAC

26th May 2010, 16:08

Centaurus/Tower Dog

Somatogravic Illusion has probably been a factor in more accidents, particularly in high performance military aircraft, than is widely understood.

At dinner this evening my colleague and I we're discussing two such instances involving CAF CF-18's. I'm sure a close look at the records would find many, many more.

In civilian flying two recent accidents, Gulf Air 072 and Aramavia 967, both have similar profiles of spatial disorientation occuring during a two engine go-around at night or in cloud. Going further back in time there are also more for those who care to look.

A critical point for consideration in this accident might be the differences in performance between the A330 and the previous types the crew may have been familiar with. A substantial difference between what they were historically used to and what they actually experienced could have had a great heightening effect on the sensation of the pitch up illusion if that is what occurred.

This is not to rule out other possibilities, but if the aircraft did do what is reported, this would be a very plausible explanation for why it did so.

ELAC

TowerDog

26th May 2010, 17:05

I love those people who claim never felt disorientation, vertigo, somatographic illusions, visual illusions...etc...

Painting with a pretty broad brush here..?

Who said they never have been disoriented or have never experienced vertigo..?

I sure have, but somatographic illusions from rotating hard has never been a problem.

Early in my instrument training and under the hood, I got vertigo a few times, but the cure was to trust your instruments, not the inner-ear sensation of being in a turn.

Liars and cheats all !

Yeah, that really added to the converstion..What is next? Whores and sluts?:rolleyes:

MurphyWasRight

26th May 2010, 17:15

Lemurian brings up an interesting point on simulators, the flip side of which is that creating conditions to induce the proposed somatogravic illusion (SI) is likely not possible in a simulator.

Point being that even if the exact scenario was trained in a simulator the G forces would not be the same as felt by the accident pilots.

This of course would make the SI even more difficult to recognize and deal with.

===

Some things cannot be simulated:

The failure of the first Arian 5 launch was in part due to the fact that the only way to truly test an inertial guidance system (in all 3 acceleration axis) is to fly it.

Belgique

26th May 2010, 17:42

A critical point for consideration in this accident might be the differences in performance between the A330 and the previous types the crew may have been familiar with. A substantial difference between what they were historically used to and what they actually experienced could have had a great heightening effect on the sensation of the pitch up illusion if that is what occurred.
Another point is: "How often does the average pilot do a sudden unexpected TOGA go-round at light-weight having just lost visual? Is not the physiological aspect of sudden light-weight acceleration at TOGA a bit disconcerting?"

It's quite a different kettle of fish doing a missed approach when already on the clocks from DA or MDA - to transitioning from an unexpected lost visual into a missed approach/go-round scenario. Certainly that's so in the simulator and most certainly in the airplane - the difference being that you can't reproduce the vestibular sensations in the simulator.

If you search the internet for the topic you'll find that the onset of the pitch-up illusion is sudden and alarming. The pilot response of pitching nose-down strongly reinforces the "sensation of steeply climbing" illusion. i.e. once you're in it you're unlikely to escape it.

Back in the 1970's, after observing a number of glider winch-launch accidents in VMC where the pilots pitched sharply nose-down just after transitioning to a steep nose-up climb, the famous UK gliding instructor Derek Piggot wrote a book on the subject, citing the many instances, and an avmed analysis of the phenomenon.

Those who haven't had avmed training, as with hypoxia, wouldn't stand a chance once in the grip of the sensation. The "stuffing the nose down" response is quite involuntary. If the other pilot wasn't suffering the same illusion at first, once the unload came on, he soon would be.

.

MD83FO

26th May 2010, 20:03

for such a thing to happen when selecting toga you would not only have to ignore the flight director and the pitch attitude but the "to low terrain" egpws.

BOAC

26th May 2010, 20:05

Correct, MD, and that is what happens.

EMIT

26th May 2010, 20:30

Murphywasright (#958)

I think you did not understand Lemurian correctly: in a simulator, deliberate use is made of the shortcomings of the vestibular organ in the inner ear.

In order to make the pilot believe he is being accelerated, the simulator cabin is tilted backwards, while the simulator visual could be showing level flight.
In order to make the pilot believe he is being decelerated, the simulator cabin is tilted forwards, while the simulator visual could be showing level flight.

When rolling in, the simulator cabin rolls tilts with the roll, with a rapidity that will be felt by the inner ear. The visual then continues to show proper roll response, while the cabin returns to upright at a rate so low that the inner ear does not detect it, and so on and so forth.

The basic working principle being that the visual channel of man(kind) is so powerfull that it will override sensations from the inner ear. Falling into the trap of the somatogravic illusion is caused by not using the visual channel - not looking at, or not believing, the (artificial) horizon.

Yes, I know how formation flying (as wingman) can topple your "internal" gyro, however, the remedy to that is just a glimpse from the corner of your eye onto your HUD or head down attitude indicator (probably not yet available in old day Tiger Moths).

BOAC

26th May 2010, 21:23

I find it very concerning that so-called professional pilots who presumably visit a 'full motion sim' at least every 6 months have 'never experienced' the very illusions of accelerations induced by pitch changes in the box.

Smilin_Ed

26th May 2010, 21:36

Catapulting from an aircraft carrier at night or IMC would surely be the most dangerous risk from SI yet rarely do we hear of these aircraft crashing into the ocean after take off.............

Having had a bit of experience with dead-of-night catapult launches in open ocean with no horizon (probably 200 times), the ONLY thing to do is to trust your instruments. Otherwise you die. As has been stated above, the transition from a semi-visual approach to a go-around can be very difficult, but it's still mandatory to trust those gauges. :=

bearfoil

26th May 2010, 22:02

The Hornet flies itself off the deck. If you don't show the boss your right hand, you sit.

Right Way Up

26th May 2010, 22:10

for such a thing to happen when selecting toga you would not only have to ignore the flight director and the pitch attitude but the "to low terrain" egpws.

One of the side affects of being stressed is the apparent hearing loss, or more accurately our inability to absorb the sound accurately.

snowfalcon2

26th May 2010, 22:17

Finally, anyone in favor of the tail-struck-first scenario could please explain the puzzle I posed a few days ago, namely how one can get an AoA of 16°+descent path angle on an A330 at approach-like speeds. So far, no one has tried.

I suggested an accelerated stall, at very low height, but it was dismissed on grounds of the A330 AlphaMax protection.

However, a quick scan brought up several tailstrike cases in A330, A340 and A320 aircraft (on takeoff as well as landing), so evidently AlphaMax protection is not always effective in preventing a tail first contact. Can anyone elaborate?

EMIT

26th May 2010, 22:47

Alpha max protects against stalling.

During take-off roll, a-max protection is not active, pitch control is direct (pull stick x amount, get elevator x amount, i.e. not y amount as modulated by flight control computer.

But anyway, contact of tail with ground occurs at lower angle than angle at which wing would stall.

PBL's puzzle is much about well, when flying and you pull, than angle of attack increases, so lift increases, so aircraft moves away from earth, so tail cannot hit earth anymore. But, as aircraft rotates, approximately around the wings, the initial movement of the tail is still down - during a take-off, the point of closest proximity of belly underside to runway occurs just after main wheels have lifted off! (at least with long aircraft).
I cannot quickly calculate anything to solve PBL's puzzle, but I hope some mysterious concepts have been cleared up.

CONF iture

27th May 2010, 03:24

PBL's puzzle is much about well, when flying and you pull, than angle of attack increases, so lift increases, so aircraft moves away from earth, so tail cannot hit earth anymore.
It is not exactly correct for a go-around maneuver when actually an altitude loss must be expected :

http://i65.servimg.com/u/f65/11/75/17/84/tri_0010.gif (http://www.servimg.com/image_preview.php?i=57&u=11751784)

barit1

27th May 2010, 11:41

EMIT may be overlooking the downward momentum of a 300+tonne mass of airplane on approach. If one wishes to instantly reverse the downward velocity, an infinite amount of lift is required, with the consequent infinite Gs imposed.

EMIT

27th May 2010, 12:35

CONFiture and Barit,

I am well aware of the inertia and the slight descent before you achieve positive climb.
I am pretty sure that PBL is aware of that as well, but PBL posted a geometric puzzle as to how it would be possible that (as speculated) only the tail would have hit the ground without the landing gear (or in case of gear up) the engines hitting the ground as well (in the initial impact that would be).

jbsharpe

27th May 2010, 12:54

for such a thing to happen when selecting toga you would not only have to ignore the flight director and the pitch attitude but the "to low terrain" egpws.

Forgive lowly SLF question here, but would the EGPWS messages sound if the thrust level didn't quite make it to the TOGA position, as was the case of the incident in Melbourne which someone linked? Would the additional thrust at this level be sufficient to create the conditions necessary for the illusion?

:ok:

CONF iture

27th May 2010, 12:59

EMIT,
If no thrust is immediately applied as specified by arc-en-ciel and A4 here (http://www.pprune.org/rumours-news/414936-afriqiyah-airbus-330-crash-47.html#post5716095) and here (http://www.pprune.org/rumours-news/414936-afriqiyah-airbus-330-crash-post5699614.html#post5699614) a scenario where only the tail cone would hit the ground is a real possibility.

RetiredF4

27th May 2010, 13:54

CONF
If no thrust is immediately applied as specified by arc-en-ciel and A4 here (http://www.pprune.org/rumours-news/414936-afriqiyah-airbus-330-crash-47.html#post5716095) and here (http://www.pprune.org/rumours-news/414936-afriqiyah-airbus-330-crash-post5699614.html#post5699614) a scenario where only the tail cone would hit the ground is a real possibility
.

Would that correspond with the debris-pattern and the amount of destruction?
I dont think so. There must have been a lot of energy involved to destroy the hull to that amount right after first impact. And according to the statement of SB the crew initiated a goaround, which is not done without power..

The tailstrike scenario is imho out.
franzl

CONF iture

27th May 2010, 14:24

RetiredF4,
That the thrust was not immediately applied does not mean it was never applied sometime during the process ...

To me this remark by someone who has been on the terrain is relevant :
The Impact point is the almost perfect print of the end of the tail cone.

RetiredF4

27th May 2010, 15:29

Now what is the normal descent rate in a NDB-approach? Something like max 1.000 ft/min. Lets make that for errors double, being 2.000 ft.
Even being late on the power in a goaround (which would make no sense at all) together with an increase in pitch and the groundeffect would dampen the impact considerably. In this case the aircraft broke up completely in the first section of the debris field, one main gear strut and the tail being located nearly together.

There is no sign of being out of control prior the impact (that was observed wings level with a nose down attitude from the alitalia crew), where schould the high descentrates come from in a nose high tail hit first scheme?

franzl

SortieIII

27th May 2010, 15:36

Inertia Rules OK?

bearfoil

27th May 2010, 16:18

How long shall the discussion continue re: events that are already known to the caretakers of the boxes? For the record, I'm going with poor visibility and a pilot who thought he was visual when he was no such thing. Sometimes pilots fly into the ground.

bear

MurphyWasRight

27th May 2010, 18:51

Emit (#962)
I understand (sadly on an intectual level only) the various methods used by simulators to trick the senses.

Lemurians point was that people who clain to have never felt SI etc are forgetting that simulators rely ont those illusions.

My point, or perhaps better a question, is whether a pilot would ever expererience the "pitch up" illusion in a simulator.

In other words does the simulator ever deliberatly cause mismatch between instruments (aircraft) and the induced motion illusion (pilot/seat of pants).
If the answer is no then then the instinctive reaction would be even harder to avoid.

fantom

27th May 2010, 19:15

SortieIII Inertia Rules OK?

Aha !

For those who have not enjoyed the A330 type-rating course at TLS, one of the sim exercises is a late switch to a parallel runway - at about 500 ft AGL. The idea is to remind you of the matter of inertia. I admit, I have been caught out a couple of times (trying to overfly a cloud, for example) when my 320 experience told me I could but my 330 experience was not good enough.

A non-precision approach may, often, lead to a late visual contact of the landing area. A 320 might make it; a 330 probably won't.

If the crew had a late sighting of the rwy and tried a swift track correction, they may have stuffed a wingtip in and the rest you know.

GarageYears

27th May 2010, 20:18

My point, or perhaps better a question, is whether a pilot would ever expererience the "pitch up" illusion in a simulator.

In other words does the simulator ever deliberatly cause mismatch between instruments (aircraft) and the induced motion illusion (pilot/seat of pants).
If the answer is no then then the instinctive reaction would be even harder to avoid. For the greatest part simulator motion systems cannot generate continuous G-loads and hence, no, a pilot would not be able to experience the same causal effects that are postulated to cause the "pitch-up" illusion in a simulator. This is a known limitation of conventional 6-DOF motion platforms. Any sustained-G maneuvers have to wash out to some kind of pitch or roll effect, which then cannot provide the same inner ear sensation, since you have already stolen that sense for an artificial purpose. Most of the time this works, but for this particular problem it doesn't.

This issue (amongst others) is what led to the development of the Desdemona simulator (joint venture by TNO and AMST of Holland and Austria respectively). This simulator is capable of generating continuous loads of 3G and was intended for spatial disorientation research including SI.

See: Desdemona (http://www.tno.nl/content.cfm?context=markten&content=product&laag1=194&laag2=197&item_id=1243)

- GY :eek:

RetiredF4

27th May 2010, 20:52

fantom
If the crew had a late sighting of the rwy and tried a swift track correction, they may have stuffed a wingtip in and the rest you know

Neither the debris pattern nor the eywitness of alitalia are supporting that kind of event.
franzl

CONF iture

27th May 2010, 21:25

Franz,
I personally vote for the tail hitting first and the boxes will confirm or not that theory, but more importantly, they should reveal why that A330 was that low that early (?) as long as we let them talk of course ...

PBY

28th May 2010, 01:11

It looks like airbus stopped believing in their almighty protections.

DownIn3Green

28th May 2010, 03:11

About time...Amen...

Sitting Bull

28th May 2010, 07:07

dear mike-wsm

before posting please take the time to actually read the thread!

this was already discussed before but please allow me to get you back into the loop:

this advisory is not an "Airbus thing" but an industry initiative in response to the DHC-8/400 accident in Buffalo.

all manufacturers have been asked to send such an advisory, Boeing included.

arc-en-ciel

28th May 2010, 11:33

CONF iture,

I did not say that on several occasion , some A320 crews did not applied power at Go-Around, they did apply immediately power, but only CLIMB trust power, so no SRS mode, no GA function, etc... if then you set the Auto Pilot back in, Aircraft goes back to the ground very rapidly and with a lot of energy, nose down, (then if you are in IMC and do not read you FMA, like AF , Somographic illusion occurs )and when you see the ground coming , breaking off the cloud layer, you have very few seconds to react and arrest the descent with AP OFF and pull up max...
Hopes this clarifies my words

MostlyHarmless

28th May 2010, 11:42

Have I really just read something that "Reminds" a professional pilot how to get out of a stall and says it's should be a memory item?

I'm stunned :ooh:

CONF iture

28th May 2010, 12:41

Thanks for the clarification arc-en-ciel.
As you made mention of 2 known events, are you aware of any kind of report on those events ?

JetThePilot

29th May 2010, 13:52

An announcement based on the results of the flight recorders analysis will be made on Sunday, it is reported. Members of the investigation team (from France, Holland, South Africa, Libya and US) have returned to Libya from France.

Contrary to conspiracy theorists re the delay of the transfer of the flight recorders to France, they were handed over days before they were transfered but the investigators completed their onsite inspection of the accident area and the wreckage prior to travelling to France to analyse the content.

bearfoil

29th May 2010, 14:41

JetThePilot

Being sceptical and jaded doesn't make one a 'conspiracist'. Lighten up! :ok:

bear

borghha

30th May 2010, 11:47

Dutch newspaper NRC (nrc.nl - Binnenland - Geen aanslag op rampvliegtuig Tripoli (http://www.nrc.nl/binnenland/article2554114.ece/Geen_aanslag_op_rampvliegtuig_Tripoli)) and other Dutch newpapers report on the preliminary findings of the investigation team that Reuters was able to read through

no indications of a terrorist attack
no indication of technical problems, explosion or fire prior to the crashIs this all?

Capn Bloggs

30th May 2010, 12:16

CONF,

are you aware of any kind of report on those events ?
Here's one of them:

http://www.atsb.gov.au/media/793232/ao2007044.pdf

JetThePilot

30th May 2010, 12:45

Here is a link to a news report on the initial findings of the investigation. Reuters AlertNet - Libya crash investigators say no technical fault (http://www.alertnet.org/thenews/newsdesk/LDE64T073.htm)

It seems, fuel was o.k., no distressed radio communication, no technical faults, no fire or explosion prior to crashing. Nothing yet to change my initial specultion:

Fatigued crew made errors in poor visibility, without reliable ground NavAids ended up attemting to recover the plane too close to the ground and crashed with engines fully powered up.

CONF iture

30th May 2010, 13:45

Merci Capn Bloggs, this is an interesting reading.
As Arc-en-ciel had mentioned two other operators, it is obviously not an isolated case.

TyroPicard

30th May 2010, 19:38

GarageYears
For the greatest part simulator motion systems cannot generate continuous G-loads and hence, no, a pilot would not be able to experience the same causal effects that are postulated to cause the "pitch-up" illusion in a simulator.
Continuous G-load is not the problem, but rapid longitudinal acceleration being interpreted as continuous pitch-up. Simulators reproduce this quite well, and the pilot may respond with nose-down sidestick in spite of the attitude indication.
And I personally witnessed this effect in an A320 simulator only last month - the trainee reached 10°nose-down at 1500 ft. AAL .. the illusion is very powerful.

RetiredF4

30th May 2010, 19:59

TyroPicard
Continuous G-load is not the problem, but rapid longitudinal acceleration being interpreted as continuous pitch-up. Simulators reproduce this quite well, and the pilot may respond with nose-down sidestick in spite of the attitude indication.
And I personally witnessed this effect in an A320 simulator only last month - the trainee reached 10°nose-down at 1500 ft. AAL .. the illusion is very powerful

Thats exactly what the simulator does to induce the feeling of longitudinal acceleration, it pitches up. So your trainee didn´t fall for the illusion, but he reacted to the real thing.

A very good proof, that a simulator is nothing more than a box full of programmed gimmicks, but not the real thing at all.
franzl

fantom

30th May 2010, 20:33

fantom follows RetiredF4. Excellent.

Are you getting a bit too geeky here? Go back to basics.

Read again that which I wrote.

A non-precision approach in difficult light, in a huge aircraft, with late visual leading to a G/A = potential recipe for disaster.

If the crew delayed the initiation of G/A - for whatever reason - that may have been the cause.

It matters little, which part of the A/c struck the ground first.

arc-en-ciel

30th May 2010, 20:50

CONF iture, full AF story soon

TyroPicard

30th May 2010, 20:53

RF4
So your trainee didn´t fall for the illusion, but he reacted to the real thing. Irrelevant since the human sensors cannot distinguish between the two - the pilot's wrong reaction and poor I/F technique is the important point.
(And being picky the simulator uses a fixed pitch angle to simulate constant acceleration, not a continuous pitch-up).

arc-en-ciel

30th May 2010, 20:58

CONF iture, the two operators I am refering to are Jet Blue (see above) and Air France.
The two event are similar but slightly different with the same result anyway, Jet-Blue was AP ON hit the FLX detent only and continued to the ground, and Air France AP OFF went to the CLB detent only and set back the AP ON and went back to the ground.
Regarding the AF incident, no official BEA report (no comment), only an internal AF document to witch I can give you a basic translation. it happened at the end of September 2009 at CDG.
Pitch escape during Go-Around on A319 with TOGA thrust not set (they are very poetic ).
The followings event have been reported spontanously by the crew, then detailled by flight analysis. At the end of september , a A319 of AF is authorized for the ILS 27R at CDG by unfavorable(french poetry) weather conditions : visibility 1100m, broken 300, scattered 200. LVO operations are not in force during this first approach (normal CDG ops, they go to LVO from BKN 200). The crew decide to conduct the approach in manual flight with FD, without A/THR
At Decision height (yes height !, in cat one !) , visual reférences are not acquired and a go-around is announced and initiated by the CPT PF (he is also an instructor as well).
The flaps comes back to 3 and the gear is selected UP when call "positive rate"is made.
The published altitude for interupted approach (french poetry) on 27R is low ,2000ft and the CPT decides "a soft go-around" (as written in french "une remise de gaz souple":ugh:).
The pitch rate is low, the trust levers are moved forward gradually and are set by mistake in the CLB detent.
AP1 is engaged very soon during the "resource" (french poetry, means something like pitching up ) when the pitch has reached 6°up.
The trurst levers are never reaching the mechanical "end" TOGA detent, and the GO AROUND is not sequenced by the automatisme.
The FMA and the AP/FD logic stay consequently in LAND mode (landing logic).
the AP, as soon as it is reengaged, triggers immediatly a pitch down . The pitch becomes rapidly negative and the airplane goes back down with a heavy negative vertical speed.
The IAS increases very rapidly with the combination of the CLB thrust and the negative gradient.
4 seconds of GPWS warnings are recorded. when in sight of the ground, the CPT disconnects immidiatly the AP and set a positive pitch.
The TLA (yes they wrote TLA ! not TL...) stays initialy in the CLB detent and will never go up to the TOGA notch.
the crew will only understand their mistake when preparing the second approach, when they realize that the active PERF page stayed in the APPR phase.
The second approach is conducted in CAT 3 without any other event.

Brilliant :D :=

http://img694.imageshack.us/img694/5899/flash1v.jpg
http://img685.imageshack.us/img685/1977/flash2a.jpg
http://img692.imageshack.us/img692/7913/flash3c.jpg
http://img21.imageshack.us/img21/7008/flash4m.jpg

RetiredF4

30th May 2010, 21:46

Quote: TyroPicard

Irrelevant since the human sensors cannot distinguish between the two - the pilot's wrong reaction and poor I/F technique is the important point.
(And being picky the simulator uses a fixed pitch angle to simulate constant acceleration, not a continuous pitch-up).

Now don´t get funny. The human senses can be tricked to think it is the same, which is the principle all simulators use. However it works only if the human in the box is following other information as well, like the instruments (showing level flight) and the speed (showing increasing) and by chance also a applicable outside visual system. In that combination the brain is likely to believe, that the pitchup of the box is a longitudinal acceleration. Because the same individual subjected to the same pitchup in the box feels a climb, iif the instruments tell him it is one.

So don´t jump to the wrong conclusions here, in the simulator the movement of the box gives an artificial feeling for the intended simulated reality, and it only works if you get tricked by the combination of your senses.
Whereas in reality you run in problems, if you get tricked by one sense only, because the others (visual, instruments, situational awareness) are reduced , lost or not observed.

So what you could find out of the reaction of your student, not falling to the intended illusion of the simulator, that his instrument cross check was not existent and therefore recognizing the correct movement of the box by his sitting muscle.

A box stays a box, also there are quite a lot of differences in simulation.

franzl