That's true but it feels better with it. :)

Hi,

So .. we know the lack of speed indication (pitot tubes) was not the cause of AF447 loss
What can be the other causes ?
Seem's it's not a big range of choices ....
1-Structural destruction (due to weather circumstances) ?
2-A malfunction of aircraft systems ? (Exept pitots tubes of course)
3-Bad behavior of the pilots ?
Note:
I eliminate the point 1 of the list due of the state of the wreck and BEA preliminary reports

Hi jcjeant,
Well... don't ask me to guess about the cause(s) now, because all my previous speculations (about engines and ice) seems to be "rumored" false. Nonetheless, I never believed to a single cause, a single upset... and neither to a single "culprit". So, I'm waiting for more official releases of informations before starting a new "speculation" about it.

I am also a SLF (whatever that stands for - assume it means "non-pilot type"). From what I understand the lowest level of Airbus control (excluding the "stuff-has-hit-the-fan-all-the-chips-are-down mechanical pitch trim and rudder) is direct law - the control surface deflection is directly proportional to the stick (or rudder pedal) position. In this regard it is exactly like a normal aircraft, and the computers merely translate the stick's position into control surface deflection without adding their own inputs or limits. In this case, and if my understanding is correct, the pilot should be able to handle the aircraft - after all, he or she has probably spent much time in his or her early flying lifetime flying airplanes that behave in exactly this way. Ultimately the Airbus aircraft are aerodynamically conventional, so they should be stable and well within a pilot's ability to fly, even without computer compensation.

I hope I did not mangle the facts too badly there, and if I did I apologize and I would welcome any corrections - but as far as I am aware, the answer to your question is "yes, they do".

Who has control of the THS in Alternate law?
Who has control of the THS in Direct law?
If the THS is in the wrong place with regards to trim, which law would you rather be in?

hy gums, did we have today to establish the fourth senior-faktor ?

in troubble:
beat the computer, aviate, navigate, communicate......

a) Normal/Alternate Law: PRIMs.
b) Direct Law: Manual wheel.
c) If THS at a wrong place: Normal/Alternate/Direct.
In any flight Law, manual trim is available (manual overide PRIMs settings without causing faults in Normal/Alternate). Manual trim imputs are prioritized over electrical imputs and PRIMs are reconfigured at manual settings position.

A330 - Normal, Alt1, Alt2 and Direct Law
 

As there is a bit of discussion regarding what happens in which law, a good explanation and summary table is provided in a document by Andy Tracy. The link provided once more is:-

http://countjustonce.com/a330/a330-flight-laws.html

I wish I had your confidence :confused:

See the threads on 200hr pilots... re - there is no "early flying lifetime".

There is little comparison between a SEP or even MEP bumbling around at 3000' (where the 200hr training was done), and a swept wing jet close to Mach and Stall limits ~35K'. We have airlines and posters on this forum saying it is "poor aimanship" to manually fly in e.g. London TMA, we have airlines forbidding crews using Manual Thrust in normal Line Ops.

I've flown Airbus FBW types for ~10 years. Not sure I've ever done the "Direct Law" handling sim practice at ~35K', let alone in turbulence, dark, and maybe with further failures.

I also fly military jet trainers (as instructor) and dong a recent Test/Check flight, the profile called for some FL350 handling inc 180 turns etc. It was an eye opener for me, and took me back ~20 years to RAF days, to recall the basics of handling a jet at high altitude. Something of course we were taught properly (in the Student guide), but a modern airliner pilot really has very little recent practice or training at this...

Nick L
SLF... Self Loading Freight :O

Takata,
Thank you for the thorough answer with regard to THS trim.

To take it a bit further.
What happens when you take your hand off the trim wheel after putting it where you actually want it and you are still in alternate law? Doesn't it run back to where the computer wants to put it? Could this be inconvenient if the aircraft was actually in a stall and you were trying to recover?

Not really, manual-trim mode is activated:
"microswitches, actuated by the override mechanism, ensure that the computers remain synchronized with the manually-selected postion."

Thanks so much. Could you kindly fill me in on why one of the um...rumors being discussed now pertains to the *possibility* of "non pilot" / "inappropriate" personnel in the cockpit during the crisis?

I'd be very interested to hear Airbus pilots' thoughts on what might have happened if the Air Caraibe pilots (for there were 2 almost identical incidents...) had *not* made the quick decision to ignore the stall warnings, when flying through high-level turbulence, with iced pitots, and in alternate law.....

Also, their actions tend to test the general rule proposed above by DeSitter,

Which obviously those Air Caraibe guys didn't.....

As a point of personal interest, does that include flight test demonstration of stalling characteristics?

Just for Comparison
 

I believe the 747-400 was the last new plane without FBW.

Can anybody visualize how it would have reacted with iced pitots in the approximate same coinditons as AF447?

I think you may have missed the point of my remark, which is that the following BEA explanation does not match the Air Caraibes occurrence: Doesn't ADR DISAGREE imply that the stall warning computer has no 'valid' airspeed?

I don't have any detail about those test flight programs. Certification sheets don't tell much: http://www.easa.europa.eu/certificat...9-06052011.pdf

Hi,
For my part, I'm still waiting to know how AF447 reacted to its pitot icing and what actually the real conditions were. If you are comparing this end result with known cases, on the same fleet, it doesn't match either any of them so far.

Power for me is in a nut shell what got them , i believe to the core that the thrust levers where at idle put there by the crew.

They flew a magnificent piece of engineering for what every reason(all though this might be one of them - let's not go there, shall we ? Nice lasses but not appropriate for the thread .. JT - in to as it has been put before "a beast", without a doubt to me they would have tried to reduce to turbulence penetration speed or lower, enter blocked pitots, and or steaming, indicated airspeed does not reduce, but in-fact appears to increase, thrust reduced further, attitude being held as best possible in the turbulence they where experiencing, still no indications of reduction in airspeed, multiple warnings going off, over-speed clacker going off, severe turbulence, do they even notice the stall warning????
Or in this case "task saturation".

Nonsense, train professionals can and do freeze when confronted with the unexpected, insert multiple unexpected and its again " task saturation" and in this case theres no freezing the sim to have a wee discussion on how to sort it out, as i have no doubt when this is all over and the cause has been found that in some way or another most of us will have to do.

There where just to many things going on at one time.

Remember Aeroperu 603 and Birgenair Flight 301, both cases where the crews where overwhelmed by the information given to them by the aircraft, both cases where the aircraft was flyable and recoverable, especially in the case of 301 where both high speed clacker and stall warning where going off and the fo knew what was wrong the captain kept the thrust levers at idle, why should 447 be any different.

when humans are confronted by a computer that is either not working, or working in a regime they are not intimately familiar with, they freeze - they go into brain lock

One of the interesting things about pilots (at least pilots from 30-40 years ago) is the tendency NOT to give up in the face of adversity. Furthermore, pilots of that age and earlier were philosophically inclined to press the big "OFF" button and revert to traditional I/F stick and rudder.

I am reminded of an older pilot colleague who, in his 50s, undertook his first heavy jet command endorsement (although he had flown Meteors in Korea). He was finding it all a bit heavy going until a mid-way through sim session involving limited panel type flying .. he emerged with a grin from ear to ear .. "it's just like a real aeroplane, mate !" Needless to say, having observed that it (DC9) was not much different to a DC3 .. he had, thereafter, no problems.

It may not be the case these days with the emphasis on button pressing .. but a freeze response certainly wasn't endemic in past times.

+1.
Let's no get confused : some military aircrafts (fighters, like F-16, M2000... but also bombers like the F-117 & B-2A) use the FBW and are inherently unstable aerodynamically.
- This instability prevents the flight without the assistance of computers.
- This instability is chosen for various factors : better hard turn performance (fighters), better stealth (B-2 : flying wing, no VS)
On the other hand, and AFAIK, civilian aircrafts (for pax) MUST be stable aerodynamically (certification). Which means that sould the computers not being available, the pilots are able to fly without them. That's the purpose of the other-than-normal-laws of the Airbus FBW, isn't it ?

I stand to be corrected, should I have forgot/misunderstood some important point.

Hi JT,

All very true.

In the past we were familiar with the way conventional aircraft "felt" with the autopilot out. We knew how to trim precisely for speed and power changes. But there is less familiarity with FBW aircraft. The only time I've "felt" Alternate or Direct Law is in the simulator. When the computers get false air speed inputs, and the FBW logic downgrades, the best time to practice is not in the middle of a thunderstorm.

Plasmech,
The captain, whose body was recovered in June 2009, is thought to have not been in the cockpit.

Three of the four seats in the cockpit were retrieved; captain's seat. co-pilot's seat (that is how the BEA identifies the seat), and "fourth occupant's seat". The fourth occupant's seat is a jump seat. The main jump seat is the third occupant's seat, which apparently was not recovered (yet).

It is presumed that the two bodies recovered were sitting in two of those three recovered seats.

The Le Figaro article used the French word "sécurité" with respect to Air France procedures. As has been subsequently learned by non-native speakers of French, sécurité can be translated as either safety or security. Similarly, the French word "sûreté" can be translated as either safety or security.

I have seen sûreté and sécurité used in the same sentence, so the French must distinguish between the two with respect to meaning. French is not my native tongue by a long shot, but based on the following from Les Aeroports Francais, sûreté is used on the ground before boarding, and sécurité is used when in the air.

A lesson from Egyptair 990 was never leave a single pilot alone in the cockpit.

Sullenberger - US Airways Flight 1549

Burkill - BA Flight 38

Didn't both these captains "instincts" have a result in the outcome of their plights.

however in-appropriate, it may be extremely relevant to this thread!

perhaps it would be better to suggest that there is a video on stupidvideos.com of a air france cabin crew doing a bit of a moulin rouge in the cockpit for the benefit if the flight deck. And let other decide if they want to look at it. You want something to take your eyes off the weather radar, that will do it!

DJ77,
Do you still have your head attached to your neck ?

Probably not as you'd have all by yourself and svarin proven how and why that airplane plunged to the depths of the South Atlantic Ocean.

mm43's post and link should have given you some consolation.

Matelo,
Let's not confuse different aspects of flying here, shall we ?
What Captain Sullenberger demonstrated was superior airmanship, decisive and quick decision making and an outstandingly good knowledge of his aircraft, down to the peculiarities of the final attitude with a Flap 2 configuration.

If you go to "the seat of the pants flying" aspect, he could have probably done better in his final speed management. I'm certainly not going to criticize any aspect of his situation management, but that aspect of the incident is, if anything , proof that old fashioned *butt cheek instinctive flying* is dead.

Lemurian,

Your illuminating clear-sightedness really enlightens this thread, thank you.

JT
Beg to disagree with your remark of 30 yrs ago.

Papa India - stick push went off three times but was dumped because it was not believed.

No one did a basic aircraft configuration check and the Trident hit the deck with the droop still retracted.

It all comes down to pilot ability and training.
We were trained to not trust the pusher and dump it.

Pitot/static failure training was also ignored.

A BAC 111 had a multiple failure which was caused by water trapped in the static/pitot lines resulting in simultaneous overspeed and stall warnings.

A fighter was scrambled to fly the approach with the aircraft whilst the skipper flew pitch power which wasn't trained in the company at the time.
Management accused him of mis reading the instruments (and being a idiot) until the source was found.

In my opinion the training department and management were to blame - again lack of ability and training.

ITCZ - I operated some of the first europe RIO direct flights.

We had a double crew - six pilots and two engineers.

No captain in their right mind (poss FO as well) would have left the flight deck for the transit through the nasty part.

It could last 1/2 hour or four hours.

Weather radar quality varied between good and absolute cr@p.

Radar turbulence detection worked on amount of water in the cloud - I have had severe turbulence in a relatively dry part of a CB.

Our transits were always in the early hours of the morning when we were dog tired and should have been sleeping.

Whether or not, and I suspect not, the crew were trained and in current practice of flying an aircraft manually in turbulence with instrument failures they faced a monumental task.

If this was the scenario and it is still not sure then why do we have two crew operation?

Why do we not have satellite radar imagery?

Why do we not have full time communications?

Why do we not have wing tip collision avoidance systems?

Cheapskates and industry leaders who put profit before moral responsibility.

I leave open the debate about substandard aircraft systems and sensors until we (if) eventually find the truth.

Allow me to go to the very basics.
There are only two things that can change the speed of an airplane. "Nose" and Thrust.

If you have indication of over (or under) speed and your engine settings (EPR, N2, whatever) are within parameters, something is "wrong" with your "nose".

The attitude indicators will show clearly if the "nose" is up or down, no big deal.

Still talking basics, if your power settings are OK, AoA OK, but airspeed indicator goes crazy it is easy to any pilot to realize he is having a wrong airspeed indication.

Now, allow me to scape from basics. The computer is flying the airplane, receives a "wrong" airspeed indication. Is the computer capable to do this simple cross-check (Power settings x pitch) before reacting?
To what I understand, the computer will react immediatly and possible wiil make a wrong input, if he got a wrong airspeed indication.

Here is where a "Human Pilot" can beat a computer logic, and thats why he should be able to shut down the computer in a split second.

Combine all this inside a CB, again the pilot knows that if the nose is up, it is probably going down shortly. Thats why he is trained not to "fight" the airplane in turbulence. On the other hand, the computer is "trained" to "flight" the turbulence to the extreme of his capacity, and then handle the airplane "upside down" to the pilot.

If in the early days CBs had to be avoided, nowadays they should be specially
avoided.
Human Pilots can handle a CB, computers can't...

Better than agenda-charged malicious theories on total loss of control in case of an ADIRU failure, isn't it ?

Lemurian, I never said they were "the seat of the pants flying", I said instinctive actions aided their plight.

We Still Need Exceptional People.

The first error is trying to define human error.

Rob, I think that part of the concern is that the pilot in the A330 does not have an AoA display as part of instrument display. (That is my understanding based upon a number of posts and explanations on how AoA figures into the FBW and protections features in various Airbus, and Boeing) airliners.

MATELO,
In this case, I apologize, but still, if we opened a thread on Capt Sullenberger's actions on that day, we'd discover that they were the results of an exceptionally disciplined mind.

SaturnV
Just my two (euro-)cents as a french native: the term "sûreté" generally addresses matters of deliberate jeopardy: theaves, enemies of state, terr¤rists and so on. This is illustrated by the term "sûreté de l'Etat", that translates to "State security". Generally again, the term "sécurité" addresses dangers not resulting from deliberate action: we use the term "ceintures de sécurité" in cars and planes ("safety belts").
Thus, most often, "sécurité" translates to "safety" and "sûreté" translates to "security", but it's true that both terms are interchangeable to some degree: e.g. the established term "Autorité de sûreté nucléaire" (nuclear safety Authority), which primarily addresses nuclear accidents, not deliberate attacks against nuclear plants.
Espère ceci aide. :}

JP:

At least Engligh and French share, from their Latin roots, ambiguitatem. :cool: We are linguistic third cousins twice removed, are we not? ;)

BEA posted this summary of the sea search operations on Monday already, but I haven't seen it mentioned here before:
http://www.bea.aero/fr/enquetes/vol....16.05.2011.pdf

Most interesting in my opinion are fig.5 and fig. 6. One is a diagram of nine marker buoys and their drift paths, from an experiment made in June 2010. Look at those crazy loops! I guess that is what persuaded them to abandon any predictions about the crash site based on the location of floating debris.

The other is a map used for planning phase 4 of the search, indicating the most likely places to find the wreck. It is based on the assumption that most (but not all) areas already covered by sidescan sonar need not be searched again, and (in contrast to phase 3) that the pingers were probably just not working.

Lemurian, Sully's successful actions were not solely the result of a disciplined mind (though I agree that was key) but also the outcome of he and his copilot being experienced pilots.

I think "instincts" is being used to apply to both understanding, practice, and experience in flying. Sort of like the way an experienced golfer selects a particular chip or pitch shot in the region near the green. Without a lot of experience and practice of what would or would not work, the choice may not fit the situation of trying to get the ball into, or near, the hole.