BA B777 Incident @ Heathrow (merged)

[bsieker]

How many of you pilots have used hand held GPS on the flight deck? (I know nobody will answer that)

GPS is a passive receiver, and the processing power required is very moderate, so it would not be a big source of RF radiation.


The reall reason they don't want you using and electrical devices during takeoff and approach is because they don't want them flying into people if a crash happens. How do you think a cell phone would feel at 100 mph?

If that were true, they would say "please make sure all hard objects are stowed securely", and not "please turn off all electronic devices".

I always found it curious that digital cameras do not seem to count as electronic devices, although they undoubtedly are.

I've never heard a flight attendant object to me using even a 1+ kg digital SLR camera during takeoff and landing.

fyi - Isn't there an airline in the EU that is installing a system that will allow people to make and receive cell calls in flight?

If so, this is going to limit the radiated RF power significantly, as the mobile phones will only transmit at minimum power, as opposed to near maximum power when trying to reach a repeater on the ground.

A possible cause to the accident could have been a failure of the autothrust system if this was engaged at the time.

Not according to the AAIB initial report, knowing how the Autothrust systems works on the B777 aircraft.

All the system does is physically move the thrust levers, and the thrust control system then does the same things as if the levers had been moved manually. According to the initial report, the autothrust system moved the levers forward, without response from the engines, and some time later the flight crew moved the levers, with the same (i. e.: no) result.

The A340 accident was totally different.

(Referring to the Accident at Toulouse-Blagnac)

It was indeed, and as had been said in the appropriate thread, the load experienced by the hull in that case was totally unforseen by the designers, unlike the loads in this crash landing, which were expected.

A better comparison between the B777 and the A340-600, if we want to go there, is the very hard landing at Quito a few months ago. Although they "crashed" on the runway, sink rate was excessive (>1000ft/min, what BEA/Airbus in an Accident Information Telex called an "extremely hard touchdown") and the landing gear was damaged in such a way that the strut compression was no longer signalled and subsequently the thrust reversers were inhibited, causing an overrun. About the same sink rate caused the tail to fall off a DC9-80 at touchdown in a certification flight in the 80s.

My point? Nothing can be derived from this accident alone about the structural robustness of the B777 airframe compared to those of similarly-sized competitors' aircraft. This one was fine here, the Airbus was fine at Quito.

[pasoundman]

" All software has bugs and one worrying statement I have heard is that sometimes a bug will take years to materialize. "

Absolutely NO.

All software does NOT have bugs. It's entirely possible to write bug free code if the right methods are used. Microsoft Windows clearly is an example only of how to get it WRONG.

What MAY take years to show itself is that the code might contain OVERSIGHTS ! It's almost impossibly difficult to test for every possible eventuality.

[yakmadrid]

Could not agree more with rubik101.


On another, not unrelated thread here on flight deck forums, regarding the bounced/baulked landing of the Iberia Airbus 320 at Bilbao recently, we have several accusatory, ignorant and puerile postings from the likes of lingasting, badboyraggamuffin and flap80, criticising the flying pilot for his lack of training, flying skills and poor airmanship.
Here we have an incident, cause unknown, involving a BA B777. I don't see any posts criticising the same qualities, or lack of, regarding the pilot flying in this instance.
Just how ignorant do you have to be before you rush into print about a perfectly capable Iberia pilot who flew his aircraft away from a potentially hazardous situation? Very, is the answer.
Just how educated or perhaps biased do you have to be before you rush to judgment regarding the pilot of the BA 777? Not very, is the answer.
The double standards and ignorance of some of the posters on this site never ceases to amaze me.
I do not profess to know, nor do I have the certainty to post an opinion on everything brought up on this site, unlike some of the more opinionated and ignorant posters on these forums.
However, I do know when an idiot posts something which is just plain stupid.
Before you post anything on this site, please put yourself in the position of the pilot concerned, carefully study the facts and the situation carefully and consider how you would have reacted in such circumstances. If you are unable to restrain yourself before rushing into print, try writing it on a plain sheet of paper and read it aloud to yourself. More often than not you will see that you have no idea what you are talking about.
Much the same as I feel now!! (you might opine)
Happy landings.
http://www.pprune.org/forums/images/statusicon/user_offline.gif http://www.pprune.org/forums/images/buttons/report.gif (http://www.pprune.org/forums/report.php?p=3845396)

[Contacttower]

My point? Nothing can be derived from this accident alone about the structural robustness of the B777 airframe compared to those of similarly-sized competitors' aircraft. This one was fine here, the Airbus was fine at Quito.


Having said that though planes do seem to be getting stronger, the MD11 that crashed in Hong Kong actually lost a wing and rolled over and that was going down at about 1100ft/min at impact if I remember. I know I'd much rather have the gear collaspe than the wings break off.

[mocoman]

highly likely that both computers were running the same software

Speaking as a real-time software engineer I find this highly unlikely.

I recall reading that many safety-critical software systems providing multiple levels of redundancy use the talents of at least two non-intersecting groups of programmers.

The two teams are tasked with achieving the same software goals but are not allowed to cross-pollinate in terms of algorithms or code; thus trying to ensure that a programming flaw or bug is not induced into ALL parts of the system being created.

:sad:

[Hand Solo]

The Quito pilots were at least given the benefit of the doubt given the challenging nature of Quito. It was only when it was revealed they'd broken the aircraft by badly handling an unnecessary visual duck under manoeuvre that the criticism began. That really isn't the same as talking about a crew that faced a sudden total loss of thrust 2 miles short of the airfield in a scenario they hadn't trained for and which was deemed to be statistically impossible.

[PJ2]

snowfalcon2
To me, one notch less flaps sounds like a not-too-bad compromise in the circumstances.

Nonsense.

I could no more see a BA crew doing this than any other seasoned professional crew. They would know instinctively that the initial response of the aircraft at that point in the approach would be do increase the rate of descent, not stretch the glide. They would know that the only means to prevent an increase in the rate of descent would be to increase the angle of attack and risk the stall in an already-compromised aircraft with many unknown faults. Read my previous post, please: I stated at in the short time available the initial response of the aircraft would be to sink and below 600' there is no altitude to recover from the initial increase in rate of descent due to loss of lift.

I doubt if the crew did this or even considered it...but, the data's not available to us, so we have to suspend judgement in favour of curiosity, don't we?

suggest It would be great if someone did the math as to what the optimum course of action would be in this kind of situation.

I suppose...to what end, however? Should we also "do the math" on Sioux City or the Gimli Glider?


Anyway, what the crew did in this respect turned out to be good enough, so kudos for that.

Not sure what to do with this statement. It's trivially obvious and circular in it's argument.

[Sallyann1234]

@FrequentSLF
Quote:Filtering components are no more reliable than any other electronics. They can and do fail.
Shielding can be damaged, left off or left unconnected after maintenance.

Boeing is installing wifi transmitter/receivers on the new 787, this means tthat Boeing is not overly concerned about trasmitting devices.
http://www.pprune.org/forums/showthread.php?t=307849

To treat all transmitters equally as 'transmitting devices' is about as sensible as considering all aircraft the same because they are both 'flying machines'.

Building WiFi into an aircraft means it is fully integrated and tested as part of the aircraft's systems. That's rather different to e.g. cellphones operating unplanned and uncoordinated and transmitting at 100x the power.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This thread is now completely pointless - total speculation and theories, most of it already invalidated before it is written, by the AAIB preliminary report.

[ribt4t]

Speaking as a real-time software engineer I find this highly unlikely.

I recall reading that many safety-critical software systems providing multiple levels of redundancy use the talents of at least two non-intersecting groups of programmers.

The two teams are tasked with achieving the same software goals but are not allowed to cross-pollinate in terms of algorithms or code; thus trying to ensure that a programming flaw or bug is not induced into ALL parts of the system being created.


I don't know how much the software has changed since the first aircraft were sold but there was a fair amount of controversy during the development of the 777 because Boeing opted not to use parallel programming teams but loaded the same code on redundant systems.

Like I said, I haven't followed the changes in the systems over the years and it may well be that a subsequent update changed this.

[Nightstop]

How long does the Trent take to spool up from idle...........

[pasoundman]

" Same incident on 27 right at EGLL and the 777 would have found the VS Car Park. "

Judging from Google Maps, 27R has exactly the same amount of grass before the runway. About 450m.

http://maps.google.com/?ie=UTF8&ll=51.471199,-0.428381&spn=0.019461,0.039911&t=h&z=15&om=0

[PJ2]

NTN;, Re, You people really make me want to puke with your ill informed bull****.

Now, here I agree with you 150% and, among more than a few, share your intense frustration. If amateurs only asked questions instead of pronouncing! The signal-to-noise ratio on this (as well as past threads such as the TAM one) is far too high to have an intelligent discussion among professionals.

Not being argumentative in re the flap question - I don't think it would have been a crew action and offer my thoughts on why. It may have - we just don't know.

best,
PJ2

[HarryMann]

As for the speculation. Really it is just a competition to try and second guess the investigation. I suspect there is a very simple explanation, which may have far reaching implications; we will know soon enough, of that I am sure.

Implications, massive, I think so too..
Quite staggered that final landing configuration is so late these days
For the crew to agree to a PR media 'event' so soon after, I imagine they are confident their procedures were 100% correct, and have no idea either.

The points about RESA would also 'upset' a rather large residents opinion group about airports and extensions to their runway systems... with the enormous length of modern runways (with bigfan engines, reverese, staggering braking capability c.f. 60's/70's airliners + spoliers high=drag devices), why aren't the approaches targeted a long way up the runway, or are they?

Local weather info... I can supply that, for the Home Counties. At 2pm precisely we expeienced an 'extreme event' squall 20 miles due North line of flight from Heathrow... so not too impressed that 'weather', and specifically windshear, albeit maybe just a component factor, being dismissed or downgraded so readily...

Great landing, same as any 'seat of the pants' flyer would have done, nose down to somewhere better than Vmin (Vmd ideally) aiming at the boundary and flare heavily in ground effect (about 100ft in this case), birds do it by nature, hang-glider pilots do it by nature, needs teaching more in early days flying school, but FO Coward got it spot on!

[Fenton Freddy]

Assuming the aircraft to be on the 3 deg glidepath at 2 miles/600 ft at the ideal airspeed but without sufficient thrust to hold that airspeed, clearly the planned 3 deg touchdown point cannot be achieved. If the thrust cannot be increased for whatever reason, the plan has to be to achieve the best 'glide' angle ('partial power glide' in this case) by flying the optimum AOA or recommended glide speed for best L/D ratio. If flaps are at a high drag position, bringing them up (if system still functioning) to a setting for best glide angle (suggested as 20 on this thread) will help move the touchdown point further forward. The only other option is to reduce ground track to touchdown point - not normally an option on a straight-in approach.

So, we now have the handling pilot assessing his revised aiming point and flying the best airspeed or AOA, and the non-handling pilot trying to solve the aircraft systems failures - good teamwork.
The revised aiming point is just before the perimeter road and airfield fence, but there is no choice but to continue for this point. On no account must the glide be 'stretched' until the very last moment in order to clear the road. It becomes obvious that by using some of the difference in airspeed between 'glide' speed and stalling speed, the aircraft can be finessed over the road and fence (well done John).
Now the aircraft has just cleared the fence but is very close to or at stalling speed with marginal tailplane authority to flare further. This results in increased descent rate into soft ground. The landing gear does a great job at absorbing the high rate of descent and collapses or is torn off through sinking into the ground, acting like a crumple zone. The fuselage now has minimal rate of descent as it touches the ground. The passengers think its just a bumpy landing and the pilots "learn about flying from that". Well done crew.

[random_element]

Hi,
Firstly I'd seem some talk about stopping non-pilots from using this forum. if any action is taken in this regard I would like to hope you won't stop non-pilots from viewing, as I have learnt a lot about the jobs you do and actually get to the truth behind the hyped media reports.

I work in the phone industry and regarding mobile phones switch on in the plane. Even having phones switched on although not in a call with still be transmitting a lot off the time as 'cell handovers' between towers will be occurring often. especially in a urban area like London so this could would be akin to being in a call, plus a number of different frequencies are used in the handover process.

[pasoundman]

Capt Groper
"ECM interference"

The acronym you meant to use is EMC (electromagnetic compatabilty) but actually what you REALLY meant is EMI (electromagnetic interference).

"EMC interference" is a nonsense phrase. Please don't use things like that or we'll all end up seeing it in the press and have to blame YOU.

[curi]

Mmm very fast to retirate the plane, comparated with the 346 of Quito for example...
http://www.aviationcorner.net/public/photos/8/2/avc_00048282.jpg

I think what this is a very serious design problem of B777... with all, from the errors learning... Airbus good know...

regards.

[formulaben]

"Imagine if you would, a businessman or woman anxious to get their messages after a long transcontinental flight. To save a few minutes they turn on their cellphone while on final appraoch knowing that they will be able to get a signal at that point . . .."


This has been mentioned a couple of times recently in posts. I just want to add as SLF that I increasingly observe wireless devices being turned on during final approach. SLF may not be talking or texting but the devices are being turned on and transmitting control signals, I expect at high power to get a signal through those small windows to a base station antenna that is designed to have low gain above the horizontal (geometrical) plane.

Normally I expect this is not a problem. But (also suggested above) if some shielding comes loose from a cable, a filter breaks, etc. perhaps the system could become susceptible.

The SLF's wireless service providers store accurate, to the second, records of access that could be checked and matched to the sequence of events. Be aware, though, that it is possible a wireless device was attempting a contact at high power but did not succeed with the base station. In that case there would be no record.I can hardly keep up with this thread, but I feel compelled to respond. Apologies if someone else has already posted something similar (I'm still on page 32!)

For over 4 years I flew a Citation X, and we knew when someone had a cell phone turned on and on the aircraft because we could hear the "ping" or whatever it is through our headset/intercom. Anyway, on one flight we were climbing though the low '30s and we encountered simultaneous loss of numerous avionics systems (I'll spare you the details, but it was a domino effect: both Flight Guidance Computers failed first, we believe.) We were left with no autopilot, yaw damper, flight director, and a loud overspeed horn (due to a lower MMO due to no Y/D) among many other cautions/warnings. It was quite surprising at the time...everything just went to pot! While we pondered how that could have happened to BOTH sets of systems, my esteemed Captain asked the passengers to ensure their phones were off. The (now scared) passenger turned his phone off. When we got on the ground we looked at the "missed calls" log and found that the time correlated with the time of our incident. His phone was one of the older analog phones.

Looking back, I wish I would have filed a report to the FAA and NTSB. I now have a VERY STRICT policy of no cells phones when flying, especially digital aircraft. In the above scenario, I don't think it would be much of a stretch to think that the A/T would have been knocked off too. Our FADECs didn't appear to suffer any consequences of the event. I hope the investigators consider this scenario.

[757flyer]

The First Officer has given an exclusive interview to Sky news, talked about the total loss of power and how he expected the worst when there was no response from the engines.

I find it surprising that he is talking to the press while the AAIB are still investigating the accident...... perhaps not a sensible thing to do.

[bilbao58]

I always found it curious that digital cameras do not seem to count as electronic devices, although they undoubtedly are.

I've never heard a flight attendant object to me using even a 1+ kg digital SLR camera during takeoff and landing.



Every time I fly Continental they tell us to "turn off anything that has a battery and an no/off switch" I just assumed it was to prevent a spark that could ignite fuel in the case of an accident.

[787FOCAL]

GPS is a passive receiver, and the processing power required is very moderate, so it would not be a big source of RF radiation.


I only said that about pilots using hand held GPS because airlines ask passengers not to use them or any other device that sends or receives.

[Hand Solo]

757flyer - Try reading post #752.

[Ranger One]

Was involved in a major incident a few years ago and Flight Crew and family were all absolutely forbidden to speak to the press never mind about contacting a publicist!!

<snort> good luck if my employers start trying to lay down the law to my family if I'm ever involved in an incident. I can't shut my wife up and wouldn't expect my bosses to have any more success.

R1

[snowfalcon2]

I could not more see a BA crew doing this than any other seasoned professional crew. They would know instinctively that the initial response of the aircraft would be do increase the rate of descent, the only means by which it could be stopped would be to increase the angle of attack and risk the stall. Read my post, please: I stated at in the short time available the initial response of the aircraft would be to sink and below 600' there is no altitude to recover from the initial increase in rate of descent due to loss of lift.

That's exactly my point. The initial response is certainly some altitude loss, but the question is about the end result: will the improved glide rate allow the aircraft to glide a longer distance until it meets Mother Nature? This is not about rate-of-descent (except for the initial transition), it's about glide rate. I have no problems if the math proves you're right, but I 'd like to see those numbers anyway.

[Hand Solo]

The point is do you have time to calculate all this academic best glide speed nonsense when you are confronted witha dire emergency at 500 feet. I doubt I am alone among professional pilots in saying I have no idea what the best glide speed is on my aircraft in a non-clean config and I'll be damned if I'm going to get the graphs out to calculate it below 30,000 feet.

[Shaka Zulu]

What utter tosh some of you write?
I'd be afraid putting my family on your flights if you really are professional pilots.

It did NOT run out of fuel.
It was NOT a freak windshear (since I landed my 777 before G-YMMM).

How can it possibly run out of fuel when procedures require you to declare a Mayday if you know you will be landing with less than Final Reserve Fuel.
They didnt. PLENTY OF THE STUFF!

To start recreating what would have been the best glide speed in dirty config is a complete waste of time. Probably somewhere around the Flap speeds as per the Vref calculations is close enough for government work.
The only thing you can do last minute if you find yourself an obstacle whilst gliding towards the theoratical max glide distance flown point is by heaving the nose up, trading energy for reduced RoD but therefore landing more short than you otherwise would have done.


You can exclude pilot error from this one (and thats ALL I am going to say about)

[CityofFlight]

Mike, great photo! Much needed levity. :) :ok:

[Halfnut]

Seeing the picture of her being lifted by the cranes I think, “Poor bird she did her best to keep her people safe.” I hope some part of her can have a fitting place in the BA home vs. all her being scrapped for aluminum cans. Cockpit trainer or cabin trainer comes to mind.

[PJ2]

snowfalcon2;
will the improved glide rate allow the aircraft to glide a longer distance until it meets Mother Nature?

In this circumstance, no, it will not.

This is not about rate-of-descent (except for the initial transition), it's about glide rate.

It is indeed about rate-of-descent. There is NO room in this scenario to discuss "glide rate". By the time any meaningful "glide rate" could be established, they would have touched down, likely on the roadway.

Retracting high-lift devices, (in this case, flaps), reduces lift and would have very likely caused an earlier touchdown even with an increased pitch attitude - the near-instantaneous problem faced by this crew was balancing the available energy from the mass (the airplane) with the need to maintain an angle of attack which would accomplish this purpose but not stall the aircraft.

They would know instinctively, (to use up bandwidth in repetition) that retracting lifting devices would require an increase in the angle of attack to retain the same vertical path, (FPA - flight path angle). They would not know their stall speed nor their angle of attack (no need for either, in normal airline operations) so they would be flying on experience for the few dozen seconds they had to assess and respond to the unfolding emergency.

[Tex37]

Curi,

Was that intended to sound so utterly stupid? Firstly, this is nothing to do with any misguided Bus/Boeing debate and secondly, there is an aircraft (albeit in the Nations Flag carrier colours) stuck, blocking one of the runways at the 3rd busiest airport in the world!
Of course they are going to move it just as soon as the AAIB say they can, also BA/Heathrow have space away from public view to store and assess the A/C. Is basic common sense to ge things back to normality ASAP.

End of rant for now.

[barit1]

IIRC, the 777 MLG failed in exactly the way Boeing intended - it departed the mounts causing minimum or no fuel spill.

Hats off to a resourceful and disciplined BA crew; hats off to the Boeing structures people. All went according to their worst-case plan! :)

Now then: Recognizing fully that the approach checklist is the fruit of many decades of experience, might it not be prudent in light of Thursday's event to assure that engines have spooled up partway BEFORE lowering gear & landing flaps? That might have given them enough extra L/D to reach the piano keys. Configuring for high drag before assuring available thrust seems, in retrospect, a questionable process.

But then, this was a one-in-many-million case...

[Self Loading Freight]

The speculation about mobile phones and other handheld devices interfering with avionics has been visited many times on Pprune, so perhaps it might be better to continue it on one of the existing threads (such as this recent one (http://www.pprune.org/forums/showthread.php?t=303972) in Tech Log) at least until and if some evidence for this being a factor in the crash comes up.

R

[Jimmyjimjim]

For over 4 years I flew a Citation X, and we knew when someone had a cell phone turned on and on the aircraft because we could hear the "ping" or whatever it is through our headset/intercom.

Audible Cell phone interference on high impedance, low gain, unbalanced, analog audio lines takes a lot(!) less than to have something interfere interfere with computer circuits or magnetic instruments.

[pasoundman]

" Quote:
You could have a laptop running and a cell phone in every seat and you still would not affect anything on an airplane.


Really? Then how do you explain this?"

Would help if you posted just a small bit of what you're quoting to get even half an idea what you're talking about !

"Called cabin for a check of equipment that may have caused interference. Found passenger seated in first class with laptop on. Model HP6220 with wireless function enabled. The passenger closed the lid when we were boarding on the ground, putting the laptop into standby/hibernate mode.

Once he disabled the wireless function, all OK. The tech people should get a heads-up on this."

Yes, wireless networking may perhaps be more troublesome than cellphones.

[N4641P]

...So 801 messages about this thing and still nobody has a friggin' clue what happened here...

I guess I will check in again when the counter hits 1600.

[wigglyamp]

The UK CAA ran a research programme into cell phone interference - results are in Paper 2003/3 available on CAA website, and followed by CAA CAP756 - PED's in large transport aircraft. The research showed definite adverse effets on compass and Nav systems under test in laboratory conditions. The worst problems were in the GSM band.
There have been quite a few reports investigated by AAIB etc of compass errors, nav display discrpencies etc attribiuted to such interference.

Not suggesting whatsoever that it has anything to do with this accident, but should alert those who don't believe their phones will have any effect to turn them off when advised by the crew.

[pasoundman]

eagle21

"I think is time pprune limits it's access to proffesionals only, this people have no idea what they are talking about."

Only 4 spelling/grammar errors in the above !

[navibrator]

If it is proven that a phone or laptop caused intereference and it crashed, can we be assured that they will be banned? I hear that Ryanair want to allow them. Turns my stomach thinking about it.

[ChristiaanJ]

All software does NOT have bugs. It's entirely possible to write bug free code if the right methods are used.Interesting statement.
We should didcuss that somewhere else....
Remember a Mars probe where somebody confused feet and metres?
Bug didn't matter....until the crunch :bored:

[gatbusdriver]

For all those that are looking at theories such as lack of fuel or windshear etc. Please stop.

The AAIB have produced a preliminary report, at 600' the engines did not respond to a selection/demand for more thrust. As to what caused that we will continue to speculate.

I personally think the crew did an amazing job.

As for whether 27L was was better than 27R, doesn't 27L have a displaced threshold (LGW operator so don't know)

Hey Shaka Zulu, is that your own personal 777 (just kidding, agree with your post)

[pma 32dd]

if this teaches us anything it's that modern aircraft still bite when you least expect it!

[DCS99]

Having lived and flown round China, I always thought the sound of the undercarriage coming down was a cue for all Chinese passengers to turn on their mobile phones. :)

(Like touchdown is a cue to release seatbelt get up and retrieve handbaggage!)

So, mobile phones are highly unlikely to be connected with this incident else there'd be B777s landing short everyday in the Far East.

I hope I'm right. Else think of the implications...

[ChristiaanJ]

GPS is a receiver only - it doesn't transmit. It still radiates LO and suchlike, and digital noise. But I totally agree the level is far too low to affect a system like the A/T.

[tmax]

thread should read
BA B777 accident @ Heathrow
thats an accident as per international laws and regulations
total aircraft damage?
thanks

[HarryMann]

Seeing as no one has attempted to answer my question as to exactly where along the runway the glideslope is targeted...

I'll ask it again, please....?

Also, doing a few sums, and taking the figures quoted above, for final (landing) flap setting by 2nm. circa 1000 ft, that leaves approx 20~25 seconds from touchdown...

To the leyman, having to re-adjust (or at least confirm) thrust for new drag/descent rate as late as 20 seconds from touchdown seems these new(?) noise abatement profiles (or are they fuel saving profiles) leave little margin for problems arising after configuration changes...

True/false?

[Self Loading Freight]

Some random thoughts:

The press event: I'm sure that the crew didn't enjoy appearing in front of the ravening horde, but I think it was necessary and useful. It has (largely) quelled the 'pilot error' speculation, it has bolstered public confidence and it gave the press something positive to write about. Also, I'd expect it to help morale within BA - who wouldn't want to be associated with such paradigms of aviation excellence?

Ideally, of course, everyone would be happy to wait quietly for information while the professionals went about their business, yet that's not human nature. Press management is a pretty unlovely affair to be engaged in, but it's there for a reason. In passing, I think the crew played their part perfectly and I hope that's inspired at least some of Fleet Street's more unruly element to give them proper respect. That may be an empty hope, but at least it's there.

The flying: Someone mentioned back in the thread the original Captain Prune's advice on taking a prang, find the softest and cheapest object in the vicinity and endeavour to strike it as slowly and gently as possible. I can't think of a better example. From what we know so far, this was consummate airmanship under extreme conditions, when any decision taken another way could and most probably would have resulted in tragedy. I very much look forward to reading the flight crew's own accounts of what happened and their thoughts as they saved the bacon.

The lack of an emergency call: given that the purpose of such a call is to alert everyone to what's happening and get things moving, I don't think it mattered (if it was even an option). If you're about to pancake a 777 into the edge of Heathrow, it's rather likely that you'll be noticed in short order and the correct deductions made! Getting on the blower would have been one of those decisions that could have made things worse.

R

[Shaka Zulu]

@GatbusDriver: I wish it was ;) but it looked strikingly similar to G-YMMM albeit with different reg.

@Tmax:
incident: if people get hurt
accident: if people get killed

[30mRad]

The instrument touch down point (where the PAR or ILS is designed to make you touch down) is a distance in from the actual threshold of the runway (and for a displaced threshold it's from that)
I don't know the exact distance, and it'll vary depending on the glidepath angle (assume LHR is 3 deg?) but it's about 1000 ft in for a 2.5 deg glidepath - although I'm not normally looking at the distance to go markers at that stage of an approach!

I have the utmost respect for the entire crew of BA038 - they did a fantastic job. Another good reason to fly with a major carrier as opposed to a tin pot one.

[Hand Solo]

Harry:

2nm does not equate to 1000 feet. 2nm is 600 feet. 3nm is 900 feet.

2nm/600 feet still leaves 40-50 seconds to touchdown.

There is nothing new about these profiles, nor are they noise abatement nor they fuel saving. They are just bog standard flying.

For the layman, you do not set the thrust a distance X and leave. It is constantly adjusted all the way down to touchdown to compensate for changes in the wind, thermal activity, up and down draughts, turbulence and many other things. To need to go from a low power setting to a higher power or vice versa along the approach path is entirely normal.

[TheOddOne]

As for whether 27L was was better than 27R, doesn't 27L have a displaced threshold (LGW operator so don't know)

No, it doesn't, in the sense that all 4 thresholds at LGW are displaced. The chevrons you can see before the piano keys for 27L are a blast pad (what you also see to your left as you turn on to 26L at Mike1 at LGW.) However, the undershoots at the Eastern end of LHR, for 27L and 27R are more generous than the bare requirement for RESA for 09L/R. The old requirement was 90M, ICAO are now recommending 240M. A recent poster here has said that both the grass areas (undershoots in old money) for 27L/R are about 450M. I guess if a smilar accident were to happen on 26L at LGW, the arrival would have been on the hard. It's a moot point as to whether or not the gear was ripped off by the excessive ROD or by the wheels suddenly being retarded by a very soft surface. Maybe the oleos would have just burst and the legs bent back, but still able to run on a hard surface.

An earlier poster also speculated on inset aiming points at LHR for noise purposes. This was also suggested about 2 years ago but thrown out. Perhaps there is now a safety case, as especially 27R has a massive excess LDA over LDR for all types?

Cheers,
TheOddOne

[fireloop]

accident: if people get killed

and/or damage to third parties...;)

[Lost in Saigon]

How long does the Trent take to spool up from idle...........


Who cares...... The engines were NOT at idle.

Both engines were running but not able to respond to the autothrottle or manual command for more power to make a small correction to the flight path.

Without the small correction the aircraft was not able to reach the intended touchdown point.

AM I THE ONLY ONE WHO UNDERSTANDS THIS?

[worldpilot]

Dropp the Pilot, I won't blame the Chinese for making or selling fake fuel.:{ The ground crew should have determined the quality of the fuel before accepting it. However though, I'm also contemplating that this accident might have been caused by some fuel problems. But then, it is no ground to blame the Chinese for anything.:=

I want to congratulate the pilots for a tremendous job well done.:ok::D

WP

[Suggs]

Mobile phones wouldn't have interfered with a 777. Mine never did.

It didn't hit any birds, there is no blood of the engine cowls.

I was on the peri track when it happened. It wasn't that windy and wasn't raining, don't believe that the engines would have stalled or surged.

A/T is irrelevant.

Both Engines failed. APU inlet door confirms this. Therefore transfer buses were off line so the generators weren't on. The engines might have been producing some residual thrust but they weren't working.

The redundancy on a 777 is massive. The EEC's (Engine control units) are independent and each has an Alternate.

The Fire protection systems can shut an engine down, isolate the hydraulics turn the generators etc etc.

I would put my money on a fault with one of the those systems.

A/c are not built with airbags or to withstand NCAP testing, the fact that the jet is still fundamentally in one peace is a real testament to the boys from Seattle.

The only thing that you cannot speculate on is that the crew did a magnificent job.

[Contacttower]

Suggs that post contains a lot assertions that we really don't know are true yet...speculation is fine (I have indulged in it a lot) but don't pretend that it is anything other than speculation.


Both Engines failed. APU inlet door confirms this. Therefore transfer buses were off line so the generators weren't on. The engines might have been producing some residual thrust but they weren't working.


I think if the AAIB thought they had actually 'failed' then they would have said so...maybe the APU door was just flung open by the force of the impact?

[ChristiaanJ]

Should we also "do the math" on ... the Gimli Glider?PJ2,
The pilots on the Gimli Glider probably "did do the math" to set up the best glide, having 'a bit' more time, and glider experience !

[gulfairs]

500 ft no power!
Time for 3 "Ah ****s"
Both of those guys should get a Gong for the excellent job of getting a dead duck onto the ground without really hurting any one.

Super job Chaps, I know I would need clean underwear prior to touch down if it had been me.
Lets wait for the recorders to be decoded into plain language.
BBG

[HarryMann]

Thanks to you both...

I was simply using figures quoted earlier, 160 kt, 1,000 ft and 2nm to get a rough idea of 'time to go'

Yes thanks, quite aware that fine, and in thermally or w/shear conditions, coarse throttle adjustments are made all the way down...

But if what I read above is correct, final landing flap and therefore thrust re-adjustment and requirement to re-stabilise descent is made at or shortly before that point... which seems approx. where things started to go wrong.

Point 2) If glideslope intersects approx. 1000 ft up runway, then BA 038 touched down approx. 700 yards short...

Since we don't know how much thrust WAS being produced on average during those last 2 nm, this figure can at least give an idea... ?

.. compared to what was actually needed on the day, in those conditions, for that aircraft in its final configuration.

[AmericanFlyer]

Flyer

They had loads of fuel on the aircraft. I'm told around 11 tonnes on approach.

If they had run out of fuel I think they may have noticed a low fuel state in the LAM hold, where they spent a little time before the approach.

You people really make me want to puke with your ill informed bull****.
http://www.pprune.org/forums/images/statusicon/user_offline.gif http://www.pprune.org/forums/images/buttons/report.gif (http://www.pprune.org/forums/report.php?p=3848421)

What does the FADEC software have to do with the amount of fuel on the aircraft? FADEC software controls the engines, does it not? If FADEC software had an error in which it did not spool up the engines when requested by pilot input, the amount of fuel remaining is unimportant.

[cargosales]

Bugger, I don't have any kind of Flight Sim game on my computer so I can't join in with the daft speculation as to why this happened :{ so I'll have to content myself with reading the AAIB report when it comes out.

In the meantime, BIG round of applause to all the crew, especially the captain for doing a captain's job and allowing his crew to get on with their jobs while he got on with managing the overall situation (or is that more idle speculation?) And applause to the new glider pilot John Coward..

As an ex gliding instructor, having to stretch an approach to make the field for whatever reason (in our case, misjudged/changed wind strength or suicidal stude trying to spoil our day, it matters not) in just a few hundred kilos of purpose built GRP glider can be seriously scary :sad:

I can only begin to imagine how these guys felt trying to do the same in something not specifically designed to glide and presumably with all the characteristics of a flying brick. :ooh: + brown underwear is my starter for 10 and I wouldn't wish those few minutes on my worst enemy.

Nice one BA crew :D:D:D

CS

[ZQA297/30]

Some wondered whether this was an accident or an incident. According to ICAO annex 13




INTERNATIONAL STANDARDS AND RECOMMENDED PRACTICES

AIRCRAFT ACCIDENT AND INCIDENT INVESTIGATION

ANNEX 13

TO THE CONVENTION ON INTERNATIONAL CIVIL AVIATION

CHAPTER 1. DEFINITIONS

When the following terms are used in the Standards and Recommended practices for Aircraft Accident and Incident Investigation they have the following meaning:

Accident. An occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight until such time as all such persons have disembarked, in which:

a) a person is fatally or seriously injured as a result of

- being in the aircraft, or

- direct contact with any part of the aircraft, including parts which have become detached from the aircraft, or

- direct exposure to jet blast,

except when the injuries are from natural causes, self inflicted or inflicted by other persons, or when the injuries are to stowaways hiding outside the areas normally available to the passengers and crew: or

b) the aircraft sustains damage or structural failure which:

- adversely affects the structural strength, performance or flight characteristics of the aircraft, and

- would normally require major repair or replacement of the affected component,

except for engine failure or damage. when the damage is limited to the engine, its cowlings or accessories: or for damage limited to propellers, wing tips, antennas, tires, brakes, fairings, small dents or puncture holes in the aircraft skin: or

c) the aircraft is missing or is completely inaccessible.

Note I.-- For statistical uniformity only, an injury resulting in death within thirty days of the date of the accident is classified as a fatal injury by ICAO.

Note 2.-- An aircraft is considered to be missing when the official search has been terminated and the wreckage has not been located.

Incident. An occurrence, other than an accident, associated with the operation of an aircraft which affects or could affect the safety of operation.

Note.-- The type of incidents which are of main interest to the International Civil Aviation Organization for accident prevention studies are listed in the ICAO Accident/lncident Reporting Manual (Doe 9156).

[bsieker]

Shaka Zulu, fireloop, tmax

this was undoubtedly an accident, although no-one got seriously injured. As was the Ibera-A340-Quito case:

According to ICAO Annex 13 (simplified):

Accident.

a) a person is fatally or seriously injured [...] or

b) the aircraft sustains damage or structural failure which:

—adversely affects the structural strength, performance or flight characteristics of the aircraft, and

—would normally require major repair or replacement of the affected component,

except for engine failure or damage, when the damage is limited to the engine, its cowlings or accessories; or for damage limited to propellers, wing tips, antennas, tires, brakes, fairings, small dents or puncture holes in the aircraft skin; or

c) the aircraft is missing or is completely inaccessible


Incident.

An occurrence, other than an accident, associated
with the operation of an aircraft which affects or could
affect the safety of operation.

I think the damage other than "damage limited to propellers, wing tips, antennas, tires, brakes, fairings, small dents or puncture holes in the aircraft skin" would adversely affect the flight characteristics :eek:


Bernd

[sevenstrokeroll]

You indicate the engines were NOT at idle...fine...what setting were they at? N1 , fuel flow...whatever you have.

you choose.


I do care about the spool up time of the trent engine...if someone knows, I hope they will post it.

You see, I have the view that they were at idle or very nearly so and when they went to add power (or allow the autothrottle to do so), things didn't happen quite right.

IF they were at a normal approach setting (granted pilots do adjust thrust throughout the approach for conditions) or somewhere NEAR normal approach setting, I think they would have been closer to the runway and not so close to the stall. Our company guidelines are quite specific about power settings and not allowing the engines to get unspooled at low altitudes.

please tell us what the N1 was according to data recorders, or fuel flow, or if installed EPR...anything...but don't just tell us "they weren't at idle".

[ChristiaanJ]

... accident: if people get killed ...Ancient discussion, look in 'Tech Log'.
Major airframe damage is also formally classed as an accident, regardless of whether there were casualties.

[Intruder]

My point is that by 600ft RA the aircraft should have been correctly configured and with approach power (~55% N1) set. A loss of thrust lever command authority at 600ft RA would only be significant if the thrust setting was towards idle to begin with, and didn't return to the normal 50-55% required with the aircraft in landing configuration.
There has been a lot of talk about the stabilized approach criteria, and a bit of talk about the 160 KT at 4 DME requirement at LHR. So far, though, I have not seen a lot about the possibility that the throttles were indeed at idle approaching 600' due to a combination of possible circumstances:

Late decel from 160 Kt to target speed (anyone care to speculate what that may have been?). Remember that 4 DME is 1200', just 2 NM or about 45 seconds before the problem was noted. If the pilots were late in selecting target speed on the MCP, the throttles could well have been at or near idle. To illustrate a similar approach, a few days ago we were inbound to HKG 07R in an empty 747 Classic. Target speed was around 128 at Flpas 25. Approach wanted 180 Kt to 6 miles (level at 2000', intercept G/S just prior to 6), Tower wanted "as fast as possible" to 5. New FO (just off IOE) was PF, put throttles to idle at 6 mi to decel to target speed, and kept them there longer than was comfortable for me. It took 2 prompts of "power up" before he responded.

To that you can add any combination of wind gusts/shear that might prompt the autothrottles to keep the power low, and it is not hard to see the situation of idle thrust at 600', otherwise configured and "stable." In VMC, our requirement is "stable approach" at 500', so a low power setting (40% N1 is my personal minimum at low altitude) at 600-700' would not be unusual in a situation like this.

After that, any glitch in one or both engines could easily cause exactly the problem this 777 saw. It is possible that the failure of one engine to respond immediately could have been interpreted as a failure of both of them to respond. From the pix of the engines after landing, it appears to me one of them was producing significantly more thrust at touchdown than the other...

[interpreter]

Why at 600 feet was there a need for additional thrust? If the aircraft was at that stage being flown manually (I believe it is normal to disconnect the autopilot at approximately 1000 feet) had the sink rate become excessive and a need for more thrust? If so why? Sudden tailwind component or sharp drop in nosewind component? As I understand it once the aircraft is established properly on the glideslope at the recommended airspeed the descent should be continuous and stable - weather permitting - until the flare. Is that correct? I believe one of the most revealing pieces of information will be the glideslope and autothrottle data from the moment the aircraft intercepted the ILS and established itself on the glideslope. Perhaps the autothrottle displayed irregularities earlier on? Also why the description of a marked bank at some stage. Was one engine not performing properly and producing marked yaw?

Fascinating - and that's enough guessing for me on this thread. Over to you guys who fly the "brutes" for your living while we amateurs shut up.

[Hand Solo]

You see, I have the view that they were at idle or very nearly so and when they went to add power (or allow the autothrottle to do so), things didn't happen quite right.

IF they were at a normal approach setting (granted pilots do adjust thrust throughout the approach for conditions) or somewhere NEAR normal approach setting, I think they would have been closer to the runway and not so close to the stall. Our company guidelines are quite specific about power settings and not allowing the engines to get unspooled at low altitudes.

Well thanks for sharing those crank theories with us. You'll be pleased to hear BA has similar guidelines along with a hard restriction at 500 feet. I don't know what the spool up time is for a Trent engine, but I can guarantee it's not 30 seconds, yet when the aircraft hit the ground the thrust levers were at the TOGA position and they still weren't getting anything from the engines.

It is possible that the failure of one engine to respond immediately could have been interpreted as a failure of both of them to respond. From the pix of the engines after landing, it appears to me one of them was producing significantly more thrust at touchdown than the other...

The AAIB have already said both engines failed to respond. That has come from hard data, not human perception.

[sevenstrokeroll]

Intruder:

I think you and I are on the same page...perhaps LOST IN SAIGON could read your post for additional clarification.

It might just be that you and I are the last on the planet to understand being spooled up at low altitude...perhaps the 777 is so magic, you don't have to watch N1 ever.

;-)

and I would have said 42% as my min, but we fly different planes.

good reading your post.

[EFHF]

The instrument touch down point (where the PAR or ILS is designed to make you touch down) is a distance in from the actual threshold of the runway (and for a displaced threshold it's from that)
I don't know the exact distance, and it'll vary depending on the glidepath angle (assume LHR is 3 deg?) but it's about 1000 ft in for a 2.5 deg glidepath - although I'm not normally looking at the distance to go markers at that stage of an approach!
From this picture it appears the GS antenna for 27L is little over 300 m, little less than 1000 ft from the start of the TDZ:
http://img260.imageshack.us/img260/8459/egll27lilsgpantennaet0.png
Here is also a sim picture with the position marked at 600 ft altitude in a simulated glide path:
http://img186.imageshack.us/img186/4783/indexphpsitesessbvrc2sntn2.jpg

[julianjarvis]

As an example of just how poor the media reporting is on this is the guardian today reported that the enignes on the plane were GE engines. This was next to a picture showing one of the engines with the RR logo clearly displayed. Idiots

[sevenstrokeroll]

can you tell us all what the minimum n1 for being "spooled up" is for this engine?

does BA have a minimum N1 setting at 500'? Or something similiar? We have different terminology perhaps, but you should be able to get my drift.

And will you tell us what the reports indicate the N1 was in the accident plane?

[Hand Solo]

It's slightly depressing that we've gone from the "Well they must have run out of fuel, I just knew it" to "Well they must have let the engines spool down too long to spool them up again, I just knew it".

At least the fuel theorists didn't have an AAIB announcement to work on. Know we've got official confirmation the engines didn't respond the idle spool theorists want us to to think thats fiction and it was all caused by a schoolboy handling error!:ugh:

I don't know what the N1 is on this aircraft, it's a RR, the primary gauge is EPR. BA requires approach power to be set at 500 ft. Approach power varies according to weight and landing flap setting. I don't know what the N1 was when the think hit the deck but reports in a UK newspaper suggest the EPR gauges were both dead before the aircraft hit the fround.

[Intruder]

The AAIB have already said both engines failed to respond. That has come from hard data, not human perception.
We don't know that for a fact. That part of the report could well have come from the interviews with the Pilots.

[moggiee]

Why at 600 feet was there a need for additional thrust? If the aircraft was at that stage being flown manually (I believe it is normal to disconnect the autopilot at approximately 1000 feet) had the sink rate become excessive and a need for more thrust? ............
It is common practice at busy, large airports to maintain a high-ish approach speed on final approach, typically 160 to 170kt - until 4 nm from touchdown. The gear would normally be up and the flaps at one of the early to intermediate settings (sorry, I don´t know what settings the 777 would use but on the VC10 I flew in the RAF it would have been the first stage, called "take-off" by Vickers).

At 4nm, the gear would be lowered and the flaps extended to reduce to "normal" approach speeds (again, I´m not familiar with the 777 but the VC10 would have been about 120-130kt).

There are a number of reasons for the high speed approach including: all aeroplanes flying similar speeds for easier ATC spacing and low drag configuration allowing lower power settings, lower fuel usage and less noise.

The downside is that the aeroplane is not placed into the landing configuration until late on the approach and as the drag increases (gear/flap extension) thrust has to be increased to compensate. Normally, everything should be settled by 500' above aerodrome level (aal) - unless, of course, the engines fail to spool up when requested - then it becomes "interesting"! If not stabilised by 500' aal, then the normal procedure would be to execute a go-around.

Hope that helps.

EDIT: Because my post seems to have upset M.Mouse so badly, may I reiterate that I am simply quoting an example of how an aeroplane with which I am familiar would fly "160kt to 4nm". Barring differences in terminology between manufacturers and differences in speed between types, the principle hold good.

I was trying to explain how an aeroplane could end up in a position whereby a power increase was needed late on in the approach and believe that the information posted above is relevant for explaining a PRINCIPLE. What I am NOT doing is passing comment upon this incident.

In addition, M.Mouse, whilst I don´t pretend to be familiar with the 777 I am reasonably familiar with BA shorthaul operations having spent 6 years teaching the self same BA SOPs to BA shorthaul cadet pilots.

Whilst the 777 may be different, last time I looked in BA FCOs, the SOP requires that if the approach is not stable by 800' aal then "consideration" should be given to the option of exectuting a go-around and Missed Approach Procedure and that if the aeroplane is not stable by 500' aal then the crew "must" go-around. Therefore, the required power increase may quite legitimately be made very late on in the approach - and whilst 600' is a bit on the late side, it's still (just) IAW SOP.

I'm quite happy to be corrected if wrong.

[pasoundman]

HarryMann
" Seeing as no one has attempted to answer my question as to exactly where along the runway the glideslope is targeted...

I'll ask it again, please....?"

The ILS aims the aircraft at the 'touchdown zone' marked with parallel white lines which are beyond the runway threshold that's marked with multiple white lines.
See them here.

http://maps.google.com/?ie=UTF8&ll=51.477441,-0.440376&spn=0.009729,0.019956&t=h&z=16&om=0

Also see ....
http://www.pprune.org/forums/showthread.php?t=88920

[Hand Solo]

Intruder - No we do know it for a fact. The AAIB don't make statements that are not grounded in hard fact and the aircrafts Quick Access Recorder has already been analysed which will have all the data on thrust lever angle and engine response. If I balls up in BA I can go into the office and ask for replay of my flight. On the PC they will show me a full run down of the incident, with a visual flight sim style picture of the aircraft path along with full representation of the instruments, FMAs and control positions. That data was all available to the AAIB. Are you suggesting they ignored that and issued a statement based solely on crew reports that they might later have to retract? You really think they are that dumb?

Sevenstroke - C'mon, do you really think that level of detail is going to be in the public domain 2 days after the incident. What is it with you and Intruder's head in the sand attitude to a highly regarded accident investigation body? They've already said the engines (plural) failed to respond, you're still trying to nail it on the crew?

[787FOCAL]

It is common practice at busy, large airports to maintain a high-ish approach speed on final approach, typically 160 to 170kt - until at 4 nm from touchdown. The gear would normally be up and the flaps at one of the early to intermediate settings (sorry, I don´t know what settings the 777 has available but on the VC10 I flew in the RAF it would have been the first stage, called "take-off" by Vickers).

At 4nm, the gear would be lowered and the flaps extended to reduce to "normal" approach speeds (again, I´m not familiar with the 777 but the VC10 would have been about 120-125kt).

There are a number of reasons for the high speed approach including: all aeroplanes flying similar speeds for easier ATC spacing and low drag configuration allowing lower power settings, lower fuel usage and less noise.

The downside is that the aeroplane is not placed into the landing configuration until late on the approach and as the drag increases (gear/flap extension) thrust has to be increased to compensate. Normally, everything should be settled by 500' above touchdown - unless, of course, the engines fail to spool up when requested - then it becomes "interesting"!

As for disengaging autopilot at 1000', that is certainly NOT the SOP. Minimum height for AP disengagement will depend upon the type of approach being flown, the approvals for the ground installations and runway, crew qualification, aeroplane avionics fit, crew qualifications etc. However, a category one approach can normally be flown on AP down to about 100' above the aerodrome in most autopilot equipped aeroplanes.

Hope that helps.

Regardless of how fast you are going in a VC-10 "less noise" should not be used in the same sentance. :E

[MR MACH]

Here is the Precision Approach Terrain Chart for LHR 27L:

http://www.caa.co.uk/docs/64/DAP_ACD_PATC_London_Heathrow_Rwy_27L.pdf

Note: The elevation of the runway is 77 feet AMSL. Elevations in feet - All other dimensions in metres.

The ILS Glide Path is aligned to give a Threshold Crossing Height (TCH) of 56 feet.

From the chart you can interpolate where the aircraft should be at 600 feet on a 3 degree glide path.

[lomapaseo]

My take is that there are lots of good questions and good postulations among the clutter in this thread.

We still have too little confirmed data and as such lots of interpretation of what little data is available.

The good and the bad of it is that there has been no smoking gun of data prior to this event that gave us a clue that this was going to happen, Sure there have been incidents (things fail) but nothing that pointed at a likely event such as this. Independent failures of the certified systems between the aircraft and the engine are unheard of in this generation of design. So the first place I would look would be either a dependent failure or a latent failure in combination with another failure condition. The latency could take the form of a safe guard or layer of redundancy that was missing and/or not detected, The other parts of the chain could be simple gotchas for any reason including crew performance leading up to the initiation of the problem.

So we need to be open about the investigation in a technical sense whilst tolerant at the same time of the human element after the fact. (no blame)

I'm still struck by the differences in the visible dirt ingested between the two engines. The one engine with the dirt stuffed into the core compressor sure appears to have been at high power.

My question at this time (which I'm sure the investigators alread know) is whether the engine (s) did actually spool up belatedly. Putting this question to rest stiffles an awful lot of speculation on this board todate.

[NigelOnDraft]

Why at 600 feet was there a need for additional thrust? If the aircraft was at that stage being flown manually (I believe it is normal to disconnect the autopilot at approximately 1000 feet) had the sink rate become excessive and a need for more thrust? If so why? Sudden tailwind component or sharp drop in nosewind component?Elementary meteorology my dear :ugh:

Suggest one reads up on what the wind does as one gets closer to the surface, particularly with a HW from the L in the N hemisphere ;)

NoD

[Contacttower]

Just to add 'fuel to the fire' with an out of context quote: (taken from a discussion about the 777's landing speeds and liaising with ATC)


As a 777-200 operator I can't see why the 300 would be better served by 170 kts to 4d - isn't the landing flap limit speed still 170 kts like previous variants - in which case isn't it a problem to slow down inside 4 miles?

As for the 200, Just to let you know that 170 to 4dme would be quite a problem for some of us who are required to have landing flap set by 900ft or the SESMA goes off = because the speed bleeds off sooooooo slowly from 160/170 (the '200 30 flap limit speed) to the final approach speed (about 135) , and this means that we end up being below 1000RA with the landing flap still running out and the power off - not good...office job <G>.

(between u, me and the gatepost we already have to cheat a little - depending on hwc we normally start the reduction to final at 5 miles - and it will take some 15 seconds before anything significant happens on the speed (= about a mile) so you wouldn't even notice it on the radar - I hope!)

Maybe approach power wasn't set? Maybe they had been kept fast and consequently the throttles did get stuck at a much lower setting than they otherwise would have been?

[Feathers McGraw]

Hand Solo

If the EPR gauges were dead, does that mean that EPR data wasn't available to the EECs on the engines? Might lack of EPR data to the EEC be what caused the engines to not respond to thrust lever inputs?

I have to say I would expect there to be more than one EPR measuring "channel" for each engine, is that the case on a Trent 800?

[30mRad]

Sorry to be a military pilot bore, but what is SESMA? There has been a few comments on it?

And as for each engine having sucked up different amounts of dirt, any thoughts that the one that ate more might have hit first? My guess is it slid right because there was right bank/yaw at impact, and therefore you'd expect the right engine to have more earth in it.

Just my humble thoughts.

[Propjet88]

There was an interesting comment a few pages earlier about it being SOP for the police to use cell jammers at certain times. Noone has picked up on it. Does anyone know the timing / location of the PM's motorcade at the time of the accident? Any technocrats have any idea how much RF power is put out by these jammers and over what distance they work?

[ChristiaanJ]

I'm still struck by the differences in the visible dirt ingested between the two engines. The one engine with the dirt stuffed into the core compressor sure appears to have been at high power.Didn't expect that from you.
The aircraft probably wasn't entirely level during 'touchdown'.
Then one of the main gears was shedded, the other was stoved through the wing.
With such dynamics, you expect both engines to 'shovel' up the same amount of dirt? Come on....
Let the AAIB sort out at what rpm the engines were.

[sandbank]

Is there any parallel with the incident in 2005 involving a Malaysian Airlines 777-2H6ER (9M-MRG) ?

Climbing through FL380 rhe crew reported a low airspeed warning on the EICAS. Then instruments showed the aircraft was approaching the overspeed limit and the stall speed limit simultaneously.

The aircraft pitched up and climbed to FL410 and the indicated airspeed decreased from 270 kts to 158 kts. The stall warning and stick shaker devices also activated.

The captain disconnected the autopilot and lowered the nose of the aircraft. The autothrottle commanded an increase in thrust which the captain countered by manually moving the thrust levers to the idle position. The aircraft pitched up again and climbed 2,000 ft. Both left and right autopilots caused the aircraft to bank and the nose to pitch down, so the captain decided to fly the aircraft manually. During the approach, the aircraft warning system indicated a windshear condition but the crew continued the approach and landed the aircraft without further incident.

It was found that "An anomaly existed in the component software hierarchy that allowed inputs from a known faulty accelerometer to be processed by the ADIRU and used by the primary flight computer, autopilot and other aircraft systems".This hadn't been identified in the original testing and certification

The FAA issued an emergency AD to prevent the operational program software using data from failed sensors

[Clarence Oveur]

Would anybody have access to schematics of the engine control system? Preferably at AMM level, but an FCOM description would be welcome as well.

If schematics are unavailable, I would be grateful if someone would take the time to give a detailed description of the system.

I am particularly interested in sensor and command input/output to/from the EEC.

[Contacttower]

Noone has picked up on it. Does anyone know the timing / location of the PM's motorcade at the time of the accident? Any technocrats have any idea how much RF power is put out by these jammers and over what distance they work?

There does seem to be some confusion over this (some newspapers initially reported that GB was travelling on the road under the approach at the time of the accident)...but it would appear that he was on board his aircraft when the accident happened.

[Feathers McGraw]

Propjet88

Jammers work by exploiting the difference in signal received by a receiver from a nearby and remote transmitter.

Since the receiver sees signal levels essentially related to distance squared from the transmitter, it means that a fairly low powered jammer can prevent the receiver hearing a more powerful transmitter at a greater distance.

What is more difficult is when you need to jam a significant bandwidth, say a whole cellular band, with a noise-like signal. The power needed is then integrated over that bandwidth so the design of the jammer needs to allow for that fact.

Since GB and co were about 1km away at the time, it would have taken a stupendous output power to affect the 777 from there, such a power level would probably be enough to disable everything electronic local to them and possibly the humans too.

[Contacttower]

Sorry to be a military pilot bore, but what is SESMA? There has been a few comments on it?



I believe it stands for 'Special Event Search and Master Analysis' and is part of BA's on board telemetry system which monitors and records aircraft performance/configuation etc.

[tykepilot]

Contactower

Please refrain from posting, your lack of knowledge is embarrassing!

[punkalouver]

bsieker said:
I always found it curious that digital cameras do not seem to count as electronic devices, although they undoubtedly are.

I've never heard a flight attendant object to me using even a 1+ kg digital SLR camera during takeoff and landing.


I have been told to stow a camera for landing.

[Contacttower]

Sorry...enlighten me then...

Apologies for my ignorance again, I have now taken the time to find out exactly what triggers it: (essentially BA's way of enforcing SOPs)


a) Event Detection
This is a selection event types detected by BAs SESMA program:


Abandoned takeoff

Altitude deviation

Abnormal pitch landing (high)

Approach speed high within 90 secs of T/D

Climb out speed low 400 ft to 1500 ft AAL

High rate of descent below 2000 ft AGL

Deep landing

Land flap not in position below 500 ft AAL

Deviation above glidepath below 600 ft AAL

Mmo exceedence

Early flap change after T/0

Pitch rate high on takeoff

Exceedence of flap/slat altitude

Reduced flap landing

Excessive bank above 500 ft AAL

Reduced tail clearance

Excessive pitch attitude

Speedbrake on approach below 1000 ft AAL

Flap placard speed exceedence

Stick shake

Go around from below 1000 ft

Tail strike GPWS windshear warning

WAS resolution advisory

High energy at 1000 ft

Unstick speed low

High normal acceleration at landing
Vmo exceedence

[pasoundman]

787FOCAL
" I said laptop running. I never said wireless running. Read and absorb before you jump. "


Show me a laptop that doesn't have wireless networking fitted and enabled as standard these days.

How many people know even how to turn it off (the networking) ?

[pasoundman]

#1
The AAIB have already said both engines failed to respond. That has come from hard data, not human perception.

#2
We don't know that for a fact. That part of the report could well have come from the interviews with the Pilots.


Yes we DO know. That info comes straight from the AAIB's site.

"the Autothrottle demanded an increase in thrust from the two engines but the engines did not respond."

http://www.aaib.dft.gov.uk/latest_news/accident__heathrow_17_january_2008___initial_report.cfm

Please check your sources.

[slink]

" Seeing as no one has attempted to answer my question as to exactly where along the runway the glideslope is targeted...

I'll ask it again, please....?"

From the AIP: 27L PAPI 420M in from THR, MEHT 65ft.

So, the PAPI (roughly in the middle of the touchdown zone, TDZ), is inset 420 metres from the painted threshold (not necessarily the end of the tarmac). The glidepath will "aim" at the same point, being calibrated to achieve this. The MEHT (minimum eye height threshold) is 65ft, which means that the pilot's eyes must be at least 65ft above ground as he crosses the threshold to see an "on glide path" indication.

If he is doing an autloand, the MEHT and the PAPI may not be relevant, as he possibly can't see them (fog - although not in this case before I get flamed :ugh:), and the autoland system will take care of the flare, landing and possibly rollout. If however, he is flying the aircraft visually, the PAPI will provide a visual reference of his position on the glide path. Bear in mind that in a larger aircraft, the pilot is higher in the airframe, so as his eyes cross the threshold at the MEHT (or hopefully, somewhere above the MEHT), the wheels will be considerable lower, so a larger aircraft will touchdown earlier than a smaller one, given that all other factors are equal. The MEHT is calculated to take this into account.

See CAP637, available from the CAA, for further definitions, and the AIP for all the numbers.

Not sure what you're going to prove now you've got the numbers though...

[30mRad]

Thanks Contacttower - I should have googled first, asked second! :)

Typepilot - poor comment :=

[pasoundman]

Hand Solo
the aircrafts Quick Access Recorder has already been analysed which will have all the data on thrust lever angle and engine response


How much extra data (if any) does the QAR record above what a modern DFDR does ?

[Eboy]

Question not too far back about specs for cell phone jammers . . .


Here is a data sheet for one series of high-power "tactical" jammers.

TX Frequency Range: 20 MHz to 4.2 GHz

Power output at the RF port up to 800 watts

http://www.antennasystems.com/cellular/trj_cellphonejammer.html


Here is a data sheet for a smaller series of jammers.

TX Frequency Range: cellular bands

Power output at RF port up to 36 watts

http://www.antennasystems.com/cellphonejammer.html

[Contacttower]

It is BA's flight data monitoring system, developed in the 1970's -more information available via here (http://www.google.co.uk/search?hl=en&ie=ISO-8859-1&q=sesma+british+airways&btnG=Google+Search&meta=cr%3DcountryUK%7CcountryGB).

And even more here in fact: http://www.theairlinepilots.com/flight/foqaflightdataanalysis.htm

[KaptinZZ]

No fire?? Mmmmmm!

I appreicate that it's been said further back that fuel quantity wasn't a problem, and what are the odds that both engines would quit as a consequence of fuel exhaustion at exactly the same moment? Not very likely I wouldn't think, but perhaps one had quit a little earlier and they were on one, started to sink, firewalled the other, but it didn't have enough fuel to deliver the goods.

Speculation I know, but jet engines don't just fail without good cause. Eye/ear witness accounts can't be relied upon as indicated back a way; some heard it fly overhead very quiet and others heard the engines roaring.

I haven't flown a 777, but I'm sure safeguards are built in to prevent the autothrottle shutting down the engines, and you certainly can't do it manually with just throttles in any jet I've flown.

I hope my speculation is wrong.

[ILS27LEFT]

Engines perfectly worked for 11+ hours.
Plenty of fuel available.

What caused this incident remains a mistery.
It could be even impossible to find a final answer through the official Inspectors especially if fuel was fine in quality and quantity: it could be that nothing else will show an anomaly except for the inexplicable loss of power.

If the fuel side of this 777 is all ok, then we are left with an electronic/software issue which could even be impossible to identify or replicate.

I think it would be better/easier for aviation to find out that this incident was fuel related.
Otherwise it is another e-factor, still linked to the low altitude and final phase of flight, which could present "electronic/software issues" which are still quite unknown because extremely rare and so hard to replicate.

The voice recorder will be useless : a series of Sh*t from the moment the engines did not respond! They probably expected to see the plane in pieces behind them.

Well done to the crew, excellent gliding skills. Your landing was perfect.


:mad:

P.S. Many said 27L has got same stretch of grass as 27R: from Google maybe it looks the same, from the air it seems that they would have touched down on the car park if same incident happened on 27right. The grass in front of 27R looks ~50/100mt shorter than the one where the 777 gently landed but I could be wrong. Distance from the last light to the beginning of runway.

[pasoundman]

KaptinZZ
Speculation I know, but jet engines don't just fail without good cause.

Indeed and the ENGINES themselves didn't fail.

Something controlling them apparently did (or fuel issues).

[M.Mouse]

From several pages back.
If flaps are at a high drag position, bringing them up (if system still functioning) to a setting for best glide angle (suggested as 20 on this thread) will help move the touchdown point further forward.

That one raised a laugh of 7/10. Effects of controls Part 2 when learning to fly as a PPL demonstrates the absurdity of that statement.

We don't know that for a fact. That part of the report could well have come from the interviews with the Pilots.

The AAIB now publish hearsay. Idiot quotient 9/10 for that one.

At 4nm, the gear would be lowered and the flaps extended to reduce to "normal" approach speeds (again, I´m not familiar with the 777 but the VC10 would have been about 120-125kt)

For quoting the completely irrelevant 9/10 with a bonus point for having not read the 20 odd quotes expanding on BA's SOPs.




Keep them coming folks I haven't laughed so much since my mother -in-law broke her arm.

[pasoundman]

ILS27LEFT
P.S. Many said 27L has got same stretch of grass as 27R: from Google maybe it looks the same, from the air it seems that they would have touched down on the car park if same incident happened on 27right. The grass in front of 27R looks ~50/100mt shorter than the one where the 777 gently landed but I could be wrong. Distance from the last light to the beginning of runway.

Put these 2 up on your screen and compare.

http://maps.google.com/?ie=UTF8&ll=51.464856,-0.430398&spn=0.004866,0.009978&t=h&z=17&om=0

http://maps.google.com/?ie=UTF8&t=h&om=0&ll=51.477614,-0.429572&spn=0.004865,0.009978&z=17


There's nothing of significance in it as far as I can see.

[greenman65]

Interesting question.

So was there. ? A message

This plane would have been making a fully automatic approach with the handling pilot ready to take over if it went pear shape.

The facts so far are the handling pilot noted the ATS did not respond to a demand. Manual correction did nothing so at this point I guess the AFCS was ditched.

What ever the reason for the ATS and or power lever input to FADEC not spooling the engines up ,the FADECcomputer programme was unable to realise it should have powered the engines up to a min power setting.

Billy Boeing is in trouble even if in the end the Captain takes some of the blame.

[Contacttower]

That one raised a laugh of 7/10. Effects of controls Part 2 when learning to fly as a PPL demonstrates the absurdity of that statement.


The statement may have been absurb...but effects of controls Part 2 when learning to fly as a PPL does not demonstrate that it is absurb...far from it, if when gliding a light aircraft with drag flap you subsquently lift the flap the gliding distance will increase.

[PJ2]

greenman65;

This plane would have been making a fully automatic approach with the handling pilot ready to take over if it went pear shape.

Where is this information from? How do you know this?

[hajk]

I'm SLF but I did development work on some avionics a long while back. I do maintain a keen professional interest on how technical systems fail.

A colleague was ex-Airbus and working on the 320. Like the triple-7 they had triple redundancy on all flight critical systems, however they used at least two completely different types of computer with programs developed by different teams isolated from each other. It meant that the software 'flew' the plane interpreting the pilots instructions according to a spec. If hardware or software failed, then it would be ignored and the remaining 'good' systems would continue.

My question is that the 777-300 also has such systems, was Boeing also so cautious not to replicate a possible technical problem three times?

[PJ2]

Contacttower;
if when gliding a light aircraft with drag flap you subsquently lift the flap the gliding distance will increase.
...but let's be clear about this: it has no relevancy whatsoever to the present discussion.

[Contacttower]

...but let's be clear about this: The statement (and perhaps the fact), has no relevancy whatsoever to the present discussion.

Absolutely, I wasn't saying it was relevant (sorry I really shouldn't have posted at all then :ugh:), I just thought it a little harsh on the person who made the original comment about the flaps because the idea wasn't as stupid as some suggested.

[737Jock]

@contacttower

Not at 100ft high!

As said before the best glide speed changes with flapsetting! With Flaps40 on a cessna you would need to fly slower for best glide in comparison to flaps up.

You would therefore need to lower the nose to increase speed.

You are talking about a situation when you are at 600ft in a cessna.

Now just think this 100ft in my cessna is about 1000ft in a jet.

[ILS27LEFT]

I cannot see very well in those pics, but in real, from the air, 27L looks like the runway which helped to save the 777 together with the pilots skills. In real, it looks as the stretch of clear grass before 27L is slightly longer than the one in front of 27R. I am not the only one stating the same in here.
I could be wrong, I have not got the official measurements, but in real life, and looking from the air, it definitely looks as if the stretch of clear grass in front of 27R is shorter than the equivalent on the L.:mad:

It might just be an optical illusion but many here stated the same impression.
In a case like this one the availability of the above green stretch of clear wet grass has been a very important factor.:)

[twistedenginestarter]

I think the most overiding thing is that Captain Burkill and his crew did a SUPERB job in what is surely a nightmare situation.
I hope they did but nobody is telling us anything yet to support that, and it's very irritating and I think contrary to the spirit of air safety.

My simplistic view is if you lose power close to the ground you choose a speed and hold it. I'd be interested in what the crew decided that speed should be. Clearly it would be different to the speed they were approaching at - perhaps close to the stall speed for the configuration (assuming they didn't have enough time or confidence to change eg flaps). My concern is the speed seemed to be choosing itself from the tiny amount of information we've been allowed to hear.

The fact they got over the fence means it was pretty good but there is suggestion it was a heavy landing. This will be an interesting sim exercise I guess. I bet somebody's been doing it a few times somewhere in secret today.

What, in hindsight, do you think was the correct way to handle the landing?

[Lost in Saigon]

if when gliding a light aircraft with drag flap you subsquently lift the flap the gliding distance will increase.

A 300,000 lb. aircraft operating 600' from the ground in a gear down, landing flap configuration does not have the luxury of retracting the flaps to zero.

[slink]

There's nothing of significance in it as far as I can see.

Checking the AIP chart, 27L has about 450M from the threshold to the road (it doesn't show the fence), 27R has about 10M less (actually on the southern edge it has slightly more, as the road in the 27R undershoot is perpendicular, in the 27L it is diagonal, shortening the distance). Don't forget that 27R has nearly twice the length of unusable tarmac before the threshold compared to 27L, making visual comparisons difficult.

This plane would have been making a fully automatic approach with the handling pilot ready to take over if it went pear shape.

The aircraft would have been on autopilot for the approach, but it's very unlikely it would have made an autoland, unless it was for training purposes, as the weather was certainly above visual minima. We usually hear the autopilot being disconnected as the crew read back "Cleared to land" - although on a nice day I have heard it much earlier than that. LHR also wouldn't have been "safeguarded" unless ATC had been given prior notification that the crew wanted an autoland, which means that there could have been work parties, vehicles or other obstructions in the critical area, making the signal unsuitable, or at least not guaranteed, for an autoland.

[737Jock]

Could I just refer to a topic in Tech log dealing with this flap/gear question!

[pasoundman]

KaptinZZ
Are you looking for a scrap, or merely a smart ar$e?

Bad day ?

I was basically agreeing with you but additionally pointing out that the idea that RR's rotating machinery itself failed is simply untenable.

Who takes responsibility for programming the FADEC / EEC ?

[PJ2]

Re remark not being stupid - understand and agree in the very broad sense regarding what one might learn at PPL school.

In this context however, it can lead people who don't understand transport category flight into all kinds of wrong areas and bad assumptions.

Just trying to maintain a modicum of informed discussion with some balance. So long as those who don't do this for a living ask more questions than make statements I think there is some tolerance from those who fly transport aircraft and who choose to post on PPRuNe, but this industry has a very low tolerance for pronouncements from ignorance, ego or wannabe bravado learned somewhere but not from within the industry. Some posters are finding that out very quickly and we come to know them equally quickly by the quality and timbre of their subsequent responses. There is far too little listening and thoughtful work going on here and it drives away those who could (and have) made intelligent presentations from their experience and knowledge. I've about had it with the nonsense myself. I sense you've got an approach that suspends pronouncment in favour of curiosity though...

[Out Of Trim]

SESMA


British Airways developed the Special Event Search and Master Analysis (SESMA) in the 1970s. Safety Services uses SESMA to publicize data (which BALPA deidentifies) to recognize safety trends and to foster improvements. BASIS and SESMA are complementary, but distinctly different, safety programs.

Safety Services compiles this information into meaningful and valuable data and analysis and publishes a monthly report in a pamphlet called Flywise. Thus, both management and flight crews are informed about the latest perils in the system and are motivated to keep up the good work and avoid what has happened to others. When watching for trends and ways to improve safety, British Airways has solid data with more than 800 Air Safety reports (ASRs) and SESMA inputs a month to draw from.
:)

[HarryMann]

Slink Thanks,

Not sure what you're going to prove now you've got the numbers though...

Well as you can see already, just getting a 'feel' for how short the aircraft touched down - looking like 7~800 metres now....

Unless the aircraft config. was totally wrong (airbrakes, thrust reversers) then that distance is a fundamental number that represents a combination of lack of power from the norm, and/or wind & thermal activity from that dialled in.

The AIB won't be coming at this from just one angle of 'what went wrong', let's use gold contacts for that switch from now on and everything will be alright...
They'll want to have all their sums add up from every angle, and one is to know exactly how much thrust was calculated as being missing over what period - whether the Flight Recorder gives that figure or not, as a double check and no doubt other methods as a third check too.

Using the a/c config at various points, wind data, and the 777's Lift/Drag polars and how short the plane came in, that isn't too much to do by hand with a sliderule, let alone plugging it in to a flight performance program and integrating the whole profile (which is what they will do).

PS. Ref. above and dirt in engines... Agree! It would not be easily visible evidence anyway. You would be looking more closely at blade erosion and dirt penetration throughout the whole engine.

[PJ2]

Out of Trim;

The smiley is very appropriate.

SESMA is an excellent safety program. British Airways is an early pioneer of using downloaded flight data to analyze safety trends. They began this work in the late 50's and have led in this important safety work since the beginning. Today, the regulator, management and the pilots (BALPA) all have access to the data in a safety culture which in my view is second-to-none. It is done in a non-enforcement environment where the truth about what is happening is more important than who is doing it - in fact "who" has no place in safety work.

There are airlines around with advanced FDM Programs which have yet to engage the final step of actually using the data and taking it seriously but that is another thread entirely. SESMA and BASIS as well as the relationship between the regulator, management and the line pilots are industry standards to which other airlines continue to aspire.

Sorry for the thread drift but it's an important piece of background information I think.

[chippy63]

Just curious- on a normal approach, what percentage power range do you normally deploy for a routine final approach?

[Bronx]

aviate1138 We can relax now as I see in the Mail that the Captain's wife is negotiating with Max Clifford to sell the Captain's story to the Media.
Excerpt from The Mail on Sunday website EXCLUSIVE: Former air hostess wife of hero pilot tells of their high-flying romance

Don't bother reading it unless you like this sort of :mad: On the Bahrain flight, there was an instant attraction between the young air hostess and the dashing pilot, whose resemblance to Mel Gibson she noted.
"Pete got on the plane and I thought, 'I fancy that, he's a bit of all right,' she says.
On the journey back to the UK I went against everything I would normally do and slipped him a note with my number on it.
I knew he had someone but I just couldn't let this person go."
:rolleyes: :yuk: :yuk: :yuk:


The F/O who was actually the handling pilot rates only a few paragraphs for a short and modest account. Maybe he aint so greedy and has more dignity. :ok:

I thank the Man Upstairs, says Heathrow crash hero John Coward"Normally in emergency situations, your training takes over. But training doesn't help much when your engines have just died and you are still short of the runway. I tried to keep the aircraft straight and when we went down I remember thinking, 'This is going to be a major catastrophe.'

All the crew did their job absolutely brilliantly but I think some thanks has to go to the Man Upstairs for giving us that little lift at the end.

I just focused on holding it up in the air as long as possible, then keeping it straight. When we landed there were several thuds. I expected there to be a major catastrophe but there wasn't.

I can't even remember how I got off the plane but there was a fair degree of panic. Then I sat in a room with lots of people rushing around me.
I was staring into space thinking about what I could do, as the adrenaline was still pumping hard."

The modest farmer's son yesterday arrived back at the house in Valbonne in the South of France where he lives with his French wife Valerie, 43, and their three children, feeling "happy but utterly exhausted".

He said: "I had barely got through the door when our nine-year-old daughter Coralie threw her arms around me and said, 'My daddy the hero.' But I don't consider myself a hero at all."

[Dunbar]

Hehe

As a lurking BA pilot with plenty of 777 time, it's amusing me no end to see all the little kids in the playground fighting over who is the most right. Well, one things for sure...flying a 777 has about as much relation to flying a Cessna as driving a sixteen wheeler truck has to taking the pushbike around the block.

Both fun, both very different.

Hours on flight sim number whatever does not a pilot make either.

Hold your horses, the report will be out soon.

An excellent piece of mitigation from the boys. That's all we know for sure.

One thing this whole episode has reminded me...most people know absolutely nothing about my job-if it's as easy as they say, they'd be doing it:)

[TheChitterneFlyer]

Well said Dunbar.

Bring the flap up? That's a cool idea... NOT! There you are sat at the correct speed for the configuration and you then bring the flap in a notch to reduce the drag... you'll then put yourself even closer to the stall!

Let's be clear about this, we've all sat at home in a comfortable armchair with a Gin and Tonic and had all the time in the world to think about this incident... John didn't have that luxury!

[Bunk-Rest]

Retracting any amount of flap at 600' and vRef in a heavy jet will guarantee ground contact even closer than they achieved. It would not cross the mind of a sane B777 captain.

[ILS27LEFT]

...you might be right.
If it is not that, you are extremely close to the truth :mad:

[PJ2]

chippy63;
Our Trent RB211 installation on the A330 uses EPR to set power. EPR is a ratio of pressures between engine internal pressures and outside atmospheric pressure and so is dependant upon a number of varying conditions in both, but an associated N1 reading on approach would around 51 to 55% depending upon weight, flap setting and to a tiny degree, headwind. A very light aircraft (330) on approach, (160,000kg), might see 45 to 50% N1....all very rough figures.

[poorwanderingwun]

Maybe this is a good time to give some consideration to a section that IS available only to those with a recognized qualification in a relevant part of the aviation world... that would include cabin crew and ground handling not just pilots and engineering staff... having established peoples' bona-fides they would have access to a thread running following an incident such as this... it's been frustrating not having access to Pprune for the past couple of days and also having to sift through some of the lamentable 'contributions' when having finally got access and there's a huge amount to catch up on.....

Maybe also, someone with a lot of time on their hands would like to sift through these pages and start a thread by pasting some of the more side-splitting postings...

[Busbert]

Given the speculation on jet fuel quality at BJS, my personal theory is that on attitude change on finals (aircraft nose up with flaps extended/gear down) a volume of free water moved in both of the wing tanks to the boost pump inlets and sent a slug of water down both engine feed lines.

Free water would have remained frozen to the bottom of the tank for most of the flight, but defrosted on descent. The water scavenge system is quite good on a B777 though...

It's a tribute to modern aircraft crashworthiness that there have been 3 recent landing incidents resulting in aircraft off runways (AFR A343 Montreal, IBE A346 Quito, BAW B772 LHR) without a single serious injury.

[Intruder]

Intruder - No we do know it for a fact. The AAIB don't make statements that are not grounded in hard fact and the aircrafts Quick Access Recorder has already been analysed which will have all the data on thrust lever angle and engine response. If I balls up in BA I can go into the office and ask for replay of my flight. On the PC they will show me a full run down of the incident, with a visual flight sim style picture of the aircraft path along with full representation of the instruments, FMAs and control positions. That data was all available to the AAIB. Are you suggesting they ignored that and issued a statement based solely on crew reports that they might later have to retract? You really think they are that dumb?

I know nothing of the AAIB, but if they are anything like the US NTSB they consider politics and public relations almost as much as safety and fact when they report. Unfortunately, they are nothing like the military Mishap Investigation Boards (of which I have served on 5) which are largely immune to politics (until the higher-level endorsements come in) and public perception.

I am also aware that a simple preliminary statement or "Initial Report" like the one they released cannot include all the details known only collectively by a relatively large number of people.

Since an initial report is necessarily based on VERY little hard information, compared to that which will become available later, there is no real risk in making a minor misstatement (e.g., "engines" vs engine) or failing to include other modifiers (e.g., "respond" [as expected])...

I don't know why you feel it necessary to hang your hat on a single statement taken solely from "Initial indications"...

Sevenstroke - C'mon, do you really think that level of detail is going to be in the public domain 2 days after the incident. What is it with you and Intruder's head in the sand attitude to a highly regarded accident investigation body? They've already said the engines (plural) failed to respond, you're still trying to nail it on the crew?
I don't know where you see my "head in the sand"... I've read a substantial number of the 400+ prior messages, plus the AAIB Initial Report, plus several news articles before making any comment whatsoever. There are many valid theories out here, but not all of them will be shown correct in the end.

What YOU seem to fail to realize is that if the engines were at a nominal approach power setting at 600', then even if they failed to respond at all until touchdown they would still have been at that same power setting, and the approach would have been nominal at least until the [attempted] power reduction before/in the flare!

I'm not trying to nail anything on anyone (except maybe the rulemakers that seem to think 160 kt to 4 NM on approach is a "good thing" that doesn't adversely impact safety). From all I can see, the Pilots handled a critical situation extremely well! Now we have to wait to find out ALL the reasons they got into that situation in the first place!

[FE Hoppy]

TAT input to fadec or T2 probes in the inlets?

and one for Dunbar,

does the 777 FBW have AOA limiting?

[HarryMann]

..... is that if the engines were at a nominal approach power setting at 600', then even if they failed to respond at all until touchdown they would still have been at that same power setting, and the approach would have been nominal at least until the [attempted] power reduction before/in the flare!Yes Intruder,

That is the sort of thing I am trying to get at too - hence the interest in how short the aircraft touched down.

It mayeven have dropped a wing at some point, and in the long run we may find that the 777 responded incredibly well to large control inputs, effectively at or below Vmc..

As FO Coward has said, he feared for everyone's lives at one point, so I fear there was a point he felt they wouldn't get over the fence at all..

Having been around and seen the appalling results of the BEA Trident deep-stall out of Heathrow over 30 years ago now, and despite this accident's implications, I can really see BA's and perhaps Boeings phenomenal relief and need to applaud at an outcome almost beyond belief... all the work that's been put in to Pilot training - indeed their whole staffing philosophy and then the massive leap forward in aircraft design; crashworthiness, safety systems, general handling tolerance and robustness ... unexpected things will happen, but the outcomes have been mitigated this time. :D

That said, we do need a new International airport - in East London, Thames Estuary - well overdue IMHO.

[Gonzo]

Cheers Mike Jenvey:ok:.......I wonder if our Tels guys came up with that pic.:}

Listened to both the R/T and my phone calls on the tapes today.....very odd, got the adrenaline going again!

[fergineer]

Free water at the bottom of the tanks......nah dont think so......jet pumps in most tanks keep the fuel and water mixed......if I remember water comes out of fuel at 1 ft per hour when the fuel is not being mixed by the jet pumps ie when the aircraft is on the ground which is why we do water drain checks after the aircraft has been on the ground for a considerable amount of time.

[Two's in]

This is an extract from a 1990 paper (publicly available) regarding scientific analysis methods as employed by the AAIB. It helps demonstrate why the answers will be ready when they are ready, and not because the Editor of a tabloid has a deadline...


Deficiencies in reports matter, because the real aim of investigations is to reduce accident
rates by making effective safety recommendations. If we don't solve the accident properly, our recommendations are likely to be ineffective. But even if we are satisfied that our investigation is sound, it will still be a failure if the recommendations are not adopted. Recommendations involve change: they are disruptive, make work, and cost money. Those with the power to implement them will therefore seek ways to avoid doing so. If the report is open to challenge on any ground - not all the data was gathered, the logic is defective, alternative propositions were not canvassed - then it will be unpersuasive, and inaction is likely to prevail…
…We start with the on-site investigation. We make an initial survey and photograph the scene. The wreckage trail is plotted, and ground scars documented. Then we examine the wreckage in greater detail – are the extremities present? Can control system continuity be established? Were other systems apparently normal? If possible, we document the cockpit control positions, and the positions of control surfaces at impact, and so on. In the case of an accident to a large airliner, the protocols to be followed are detailed in the Manual of Accident Investigation (ICAO, 1970). Witness interviewing, document retrieval and detailed examination of the wreckage follow. In all of this phase, the work can be characterised as data gathering and documentation. There are protocols for each part: how to plot the wreckage trail, witness interviewing techniques and so on. While this phase is in progress, the news media will be demanding to know what caused the
accident, and whom to blame. Of course, we tell them that the analysis cannot be started until all the data have been gathered. Of course this is untrue, but it serves to get them off our backs. In the first place, it is untrue because that is not the way the human mind works. The mind seeks to join bits of information together to make sense of them. At quite an early stage, some parts of the puzzle will become clear. It will be possible to characterise the impact as steep or shallow angle, and high or low energy. If the aircraft started to break up before impact, this will soon be known. The answers to these and other questions will give rise to possible sequences of events, and so guide the search for supporting or rebutting information. At the same time, we must be aware of the danger of the 'glimpse of the blindingly obvious'. The thing that 'obviously' caused the accident may, in reality, have had nothing to do with it. Basic data should still continue to be gathered, and alternative explanations sought. Another reason that analysis starts before all the data is available is that an unguided search of the mass of documentation associated with an aircraft and its crew is likely to be fruitless. We need to be guided by some positive line of inquiry. If a mechanical problem seems likely, the airframe logbooks may have useful information. If the pilot may have been fatigued, crew
flight and duty time records are likely to be relevant. In other words, the search for data is guided by some theoretical propositions, which the data may support or rebut. (There is a distinction between hypotheses and propositions. Hypotheses will be tested statistically, by examining a sufficient number of samples to support or reject the hypothesis with given confidence. A proposition, on the other hand, is a possibility arising from some theory, which we may or may not find that our data fits).

[KaptinZZ]

pasoundman, and the concept of fuel exhaustion in a two crew, state of the art airliner is equally entenable, but it has happened, and will continue to, happen. Unfortunately!!

And I am not stating that this is the case here, merely putting it forth as a possible theory, and this is, after all, Professional Pilots Rumour Network.

What I do contend though is that nobody can say with any degree of authority, or even any authority at all, with the exception, perhaps, of the two crew members, what actually happened, and whilst they can relate what happened, they may not be aware of the cause.........or they may be.

The rest of us are reading the newspapers, reading PPRuNe, and listening to hearsay, so hypothesize all you wish, but please don't put anything forward as fact until the accidnet investigation team have done their work.

The one thing I would be prepared to guarantee though is that BA management is in ar$e covering mode.

Whatever the cause, the crew did a great job over the last 500-600?? feet, and whatever the outcome, I wish the two crew well in what will undoubtedly be the most difficult time of their professional flying careers, or probably their entire lives.

[matblack]

This is an article from 2006. It relates to a GE90 and not an RR but it's interesting.

"The Unthrustworthy 777
Air Safety Week, Oct 9, 2006
Emergency Airworthiness Directive Issued For The 777's GE90 Thrust Rollbacks

An emergency Airworthiness Directive (AD) issued September 30 stems from two occurrences of engine thrust rollback during takeoff on Boeing 777-300ERs, which are powered by General Electric GE90-115B engines. The concern is that the GE90 engines powering Boeing 777-200LRs and 300ERs could suffer dual thrust reductions on take-off, with potentially catastrophic consequences.

In the two instances cited, just the one engine was affected but because it's software-related, the FAA cites the possibility that "a dual-engine thrust rollback could occur just after V1 (takeoff decision speed after which takeoff is to proceed even after an engine failure). This would result in the airplane not having adequate thrust to complete the takeoff. A dual-engine thrust rollback, if not corrected, could result in the airplane failing to lift off before reaching the end of the runway or failing to clear obstacles below the takeoff flight path."

Trouble-shooting technicians have found that the two cases in which there were single-engine thrust reductions during takeoff were the result of a flawed software algorithm in the Full Authority Digital Engine Control (FADEC). The emergency AD requires operators of GE90-115Bs powering 777-300ERs as well as GE90-110Bs powering 777-200LRs to amend their procedures to prohibit takeoffs at anything less than full-rated thrust. This is being stipulated because the rollbacks are only likely to occur at reduced powers, during the so-called "balanced field" takeoffs. When the power levers are set to maximum, the predictive software is out of the picture. For the foreseeable future, passengers on lightly loaded 777's are liable to think that they're on a shuttle launch."

[FLCHG]

Was there a third pair of eyes on the Flight Deck?... There has been no mention of the RP...

[HotDog]

There was; crew complement consisted of Capt., Snr.FO and FO. as reported somewhere in this thread.

[CarltonBrowne the FO]

Intruder, having dealt with the AAIB in the past they are not concerned with publicity or politics in the way the NTSB is; they will refrain from commenting until they have assessed the available evidence. I believe this is because they are a purely investigative agency, whereas the NTSB has a much wider remit.
As for some of the less informed posters, I found this thread easier to follow when the servers were jammed solid. Danny, can we slow them down again please?

[Joetom]

Buzzbox,
I'll say it again:


TAT Probe Icing.......
..............................
..............................
Even if this was the case, would the FADEC not hold idle above some low set N1/2/3 limit and the undershoot would not have been so large?

[G-CPTN]

WRT the difference between the approach to R27L versus R27R (based solely on Google/Wikimapia, not actual local knowledge) R27L has obvious buildings and a highway as well was a perimeter road on the runway centreline, whereas R27R 'only' has car parks (but are these ground-level or multi storey?).
Landing short (even shorter than BA038 achieved) on either would have been disastrous, but R27L would have involved the Air Canada Cargo Facility buildings and the A30 highway (with occupied vehicles) against 'just' mostly unoccupied vehicles.
http://wikimapia.org/#lat=51.471359&lon=-0.414562&z=15&l=0&m=a&v=2
(You can pan and zoom the above view).

An even earlier touchdown approaching R27L might involve a water landing, whilst R27R appears to be domestic housing . . .

(none of the above seem preferable to reaching the RESA)

[autoflight]

Were the thrust levers selected to the maximum power position during the period when the engines failed to respond?

[Wornout Rubber]

Various theories abound, and hopefully soon the AAIB will give us the answers, and the speculation will end.

It may have been caused by a whole spectrum of malfunctions.

One thing for sure is that this particular incident was very unusual.

The crew did as well as they could given the bare seconds they had to cope with a highly unusual event.

Although not stating a possible reason for the incident (and hopefully this post will not be seen as imaginative speculation, but leaning more towards disccusion), the topic of fuel crossfeeding on the approach is an interesting one.

The Boeing 777 FCOM (12.20.3) states that "Fuel balancing may be done in any phase of flight".

I do not know if this applies to other Boeing types or indeed Airbus aeroplanes. But I am sure you gurus out there can comment.

Now, if fuel sometimes does get contaminated (with water or detergents etc.), then would it not be prudent NOT to fuel balance close to the ground (approach, landing or go around). Obviously, configuring both engines to one fuel tank exposes one to additional, perhaps unnecessary risks.

Do UK Airlines have a policy on fuel crossfeeding close to the ground?

As, I said earlier, this post in no way implies that this particular 777 was crossfeeding, it is merely to raise the topic, which MAY have some relevance.

(Please feel free to delete the post, if it does to meet the required standard).

[safetypee]

Just seeking some perspective on the timing of the events, all values approximate with many assumptions.
Standard approach at 200 ft/sec (120 kts average GS), ROD 600ft/min; time to threshold from 2nm (12000 ft) ~ 60 sec, flare 10 sec from 50 ft.
With unresponsive engines at 600 ft:- worse case (no thrust) in this class of aircraft, might (IMHO) result in 9 deg glide path (1800 ft/ min 30 ft/sec), but this is not achieved instantaneously and probably not achievable at all before a flare would have to be commenced at a much earlier height than normal (20 sec or less to ground contact) – not the case.
With reduced thrust (flt idle), a 6 deg glide path (1200 ft/min, 20 ft sec) might be expected, but again not instantaneously (30 sec to ground contact) - unlikely.
A more reasonable scenario is a slightly reduced thrust setting, that used for deceleration from 160kt to stabilize at Vref, thus a thrust increase would be required before 500ft, but the thrust change was not obtained (engines unresponsive).
Accident geometry:- Touchdown ~1200 ft short of runway. Thus, distance traveled during the period of reduced thrust 12000 – 1200 = 10800ft. Which at 200ft/sec (no significant speed reduction until the flare) takes 54 sec.
Flare time 10 sec from 100ft (assume 100 ft flare commencement height in a reduced power condition – reducing to Vs), thus 500ft altitude loss in 44 sec gives an average descent rate of ~ 11 ft/sec. This ‘modest’ value might be due to initially trading airspeed for descent rate (height).
N.B. this does not equate to, determine, or otherwise infer the touchdown ROD.

The perspective:- Many viewers will take 44 secs to read this post, some will take longer particularly if they attempt to understand ‘the situation’ (calculations), which involves higher mental workload.
Whatever the cause of the problem, this perspective indicates why the crew did such a good job.

[whattimedoweland]

Fantastic job by all.Both Flight Crew and Cabin Crew.:D

I'm not qualfied in flying a plane but seems like a professional job boys.
I am qualifed in the cabin and can only hope I will react as well as my colleagues,if the need arises.

WTDWL.

''Ladies and gentlemen,your flight today will be 12 hours and 10 minutes.The safety video will take 5 minutes.By putting your newspapers down now,you'll have a better chance of reading them tomorrow''!.

[rr merlin]

I personally think it was down to spark plug failure probably bpr6 when we all know it should have bpr9s. well it makes as much sense as some of the other cr*p posted on here. whilst i understand that you real pilots out there need to make sense of this as quickly as you can, this thread has been hijacked by ifs, whatifs, buts and maybees . The only facts at the moment are THAT THE PLANE CAME UP SHORT AND THE CREW SAVED THE DAY.

[whattimedoweland]

rr merlin,

Fair enough but we're all human and all have an imput(right or wrong).

WTDWL.

''Lifes not a piece of string,it's short''!!.

[ManaAdaSystem]

The conditions on this particular day was less than favorable for a normal landing, not to mention an emergency one. Wind on the ground was 10-15 kts, but 30-40 kts at 1000-2000 ft. Not unusual, but it was a fairly bumpy ride when we landed just before BA 038.

30 seconds. So you expect the flight crew to inform ATC, make a PA, try to figure out what happened to the engines, how to rectify the problem and what to do next during this very limited time? You are all prepared for a dual engine failure at all times, are you? This crew did what was expected of them, saved everybody on board!

I really hope (and expect) that the entire crew of BA 038 get the proper psycological treatment after this unfortunate accident. God, I (think) I know how I would feel after planting my aircraft on the lawn 200 yards before the runway, no matter what caused it in the first place! The guilt!

To the entire crew of BA 038, I take my hat off to you all! Congratulations! Job well done! :D:D:D:D

[787FOCAL]

Show me a laptop that doesn't have wireless networking fitted and enabled as standard these days.

How many people know even how to turn it off (the networking) ?

If a laptop has an internal card it is disabled by default until you hit the Fn and F2 key (on most laptops) at the same time. They do that so you don't get hacked. It also kills the battery.

But this is a mute arguement as there would be nobody with their laptop on at this point of decent.

[787FOCAL]

To the entire crew of BA 038, I take my hat off to you all! Congratulations! Job well done!

Be careful. Remember the guy that flew that A340 into the Azores dead stick was a hero for a few days until they figured out it was his dumbass that caused the whole thing in the first place. :rolleyes:

[HarryMann]

Wind on the ground was 10-15 kts, but 30-40 kts at 1000-2000 ft.

Thats a fair to middling wind-gradient that, potentially 20kts over 1000', if mainly a headwind, necessitating significant a/c acceleration. It was rough and squally nearby all lunchtime, at one time maybe gusts of 30-40 mph at ground level, quite unstable air mass then.

[CYPR]

Excellent explanation Safetypee.

[r011ingthunder]

Right, I'm sick of this. "What if we praise the flight crew and it turns out they were at fault?"
I don't give a fiddler's f**k.
At the moment, and as it stands, they brought a malfunctioning jet in to land short within a very short period of time. Everyone survived, and injuries, I believe, were only minor.
Even if, they were initially at fault, which I might add, has absolutely no grounding, and seems less likely given BA & WW's actions, they still managed to recover enough to save all souls.
I would really like to see less people warning against praising the flight crew. Is it so difficult to acknowledge a job well done? Can you honestly say that praise is not due when lives were saved, regardless of the cause?
Oh, and I couldn't give a toss what way husband met wife or who's kids are who's, what sort of gutter trash journalism is that?
/rant over/
r011in

[mocoman]

Ribt4t said;

because Boeing opted not to use parallel programming teams but loaded the same code on redundant systems

Interesting :8 ; tell me more please. :cool:

[787FOCAL]

So if a Doctor miss diagnosed your child and almost kills them, but then through whatever miracle manages to save them you would praise the Doctor?

:ok:

[r011ingthunder]

"So if a Doctor miss diagnosed your child and almost kills them, but then through whatever miracle manages to save them you would praise the Doctor?"

Until it was proven that the doctor had "almost killed" my child, it would never even occur to me to think along those lines. That is a ridiculous analogy.

[KaptinZZ]

787 Focal, that's exactly the point I make, but it doesn't detract from the fact that they did a great job AFTER the event. With you ro11ingthunder, on that, I agree.

It may or may not transpire that they were at fault, but it was a job well done to save the pax and themselves.

What happened before? We'll have to wait for the investigators' report.

Is anybody placing any credence on posts here on throttle positions, etc? Where did the information come from? I don't believe any of the crew have posted, and the texts of interviews haven't been published, so it's all hearsay.

By all means put forward your theories guys, but please don't represent anything as fact that you don't know actually happened, and I believe none of us know that at this moment. If it was reported that Capt ............ said "............" in the daily papers, that is not fact.

[barit1]

Were the thrust levers selected to the maximum power position during the period when the engines failed to respond?

You gotta be kidding! :eek:

[787FOCAL]

Until it was proven that the doctor had "almost killed" my child, it would never even occur to me to think along those lines. That is a ridiculous analogy.

You must be female. Men always prepare for the worst and are pleasently happy when the worst does not happen. Females usually look for the best and are pissed when it does not happen.

:cool:

ps. I am hoping that it was not their fault, but with the track record of most accidents being human error the odds are against us.

[Belgique]

Did the crew think to press the TOGA button?

It should have circumnavigated the glitch.... perhaps it should be(come) an SOP...

Can't recall having seen that mentioned anywhere yet....

[r011ingthunder]

"You must be female."
Eh, all I can do is point out that this supposition on your part can be filed with your tendency to point the finger of blame at the flight crew... in the midden heap.
Last time I checked I was a red-blooded male.

PS Oh Lord I wanted to leave it at that, but I just couldn't. What the HELL made you come out with a statement like that when what this thread is about is trying to ascertain the cause of the accident in Heathrow? I have read some seriously spurious posts on this thread, some of which reflected very badly on the intelligence of the poster, but your's, my friend, takes the proverbial biscuit!

[Mad (Flt) Scientist]

@787FOCAL

I think it would be fairer to say that most accidents have human error as a significant factor; it's rare that human error alone is the cause, usually something else either produces the conditions for the error, or fails to detect or protect against the error.

[787FOCAL]

I think it would be fairer to say that most accidents have human error as a significant factor; it's rare that human error alone is the cause, usually something else either produces the conditions for the error, or fails to detect or protect against the error.

Last time I checked it looked to me that 99% were human error. Has this changed?

[r011ingthunder]

"Last time I checked it looked to me that 99% were human error. Has this changed?"
Can I ask when it was you "last checked", and what it was you checked, and also how you calculated your percentage figure?

[bubbers44]

What ever the cause of engines failing to respond at 600 ft the pilots did the best they could do to get it over the fence and the airport level property to put it down. It saved a lot of lives and they should be commended for it. We are required to be stabilized on our op specs IFR and VMC approaches and obviously if we do that loss of thrust control will not get you to the runway if thrust is low.

Flying light airplanes it was easy to keep the pattern tight so you could glide in but once configured and on speed no wide body could make the runway with a loss of power.

No one established on an ILS could land from 600 ft properly configured with any loss of total power. If one engine was fully functioning, sure. In this case neither engine would spool up. The captain said that.

[Mad (Flt) Scientist]

I don't know the % which identify human error, but it's rare that a single cause exists.

Even where the human makes the fatal error, you can always say "the designers should have ...."; there are a lot of systems on aircraft today designed to try to detect human errors, and more proposed. And often a bad or mis-thought MMI can contribute to human error too.

[787FOCAL]

Can I ask when it was you "last checked", and what it was you checked, and also how you calculated your percentage figure?

That would cause me to reveal who I work for.

[PA38-Pilot]

Last time I checked it looked to me that 99% were human error. Has this changed?

According to http://www.planecrashinfo.com/cause.htm, it was never "99%".

Please, do some research before posting, instead of blaming everything on pilot error. We are humans, but we know how to do our job.

If you so much "hate" pilots, and blame them for everything, then what are you doing here?

[RobertS975]

Not for a moment taking anything away from the efforts and skill exhibited by the crew, but the real miracle here is that there was no consuming fire. It is the inexplicable lack of fire that allowed all to survive.

[r011ingthunder]

"That would cause me to reveal who I work for."
Ah, stop it will ya? It would not have revealed anything had you not just made that statement! I can't take anymore of this drivel from you. I'm not going to propagate a debate with you by responding further to your inane posts. I'll await the official outcome, and meanwhile think the best of the flight crew and cabin crew who did a fantastic job in awful circumstances.

[Mad (Flt) Scientist]

Bit off topic (mods, move somewhere better if you like, I guess) but to follow up the causes and pilot error issue.

The NTSB releases various statistical data. Annual Review of Aircraft Accidents 2003 (http://www.ntsb.gov/publictn/2007/ARC0701.pdf) was the first I checked.

On pages 13 and 14 it has a couple of graphs showing various causes, and also a discussion in the text.

Within each accident occurrence, any information that helps explain why that event happened is designated as either a “cause” or “factor.” In addition are findings that provide information of interest to the investigation. For most of the 10-year period [1994-2003], personnel were cited as a cause or factor in 70 to 80% of all Part 121 accidents, followed by environment-related causes, and then by aircraft-related causes.

Certainly not 99% in that sample.

(Incidentally, "personnel" isn't just pilots; any human error would be counted)

[787FOCAL]

According to http://www.planecrashinfo.com/cause.htm, it was never "99%".

Please, do some research before posting, instead of blaming everything on pilot error. We are humans, but we know how to do our job.

If you so much "hate" pilots, and blame them for everything, then what are you doing here?

Who said I hate pilots? My family's livelyhood is provided by aviation of which there would be none without pilots. I wasn't blaming them I just stated a statistic. Hopefully you read your training manuals and absorb the information better than you are showing here.

The 99% was not encompassing all aviation, just a certain sect and to explain what sect I mean would cause me to reveal. Caphece?

[r011ingthunder]

"Caphece?"
NO! And it's spelt CAPICHE.
Go away.

[787FOCAL]

I'll await the official outcome, and meanwhile think the best of the flight crew and cabin crew who did a fantastic job in awful circumstances.

Thats what I am doing. You don't see me speculating over the possible causes do you?

"Caphece?"
NO! And it's spelt CAPICHE.
Go away.

Go away? I been here way longer than you Mr. Just signed up in January 08. :E:E

My other profile was signed up in 2000 and has 1000s of posts. :ok:

[PA38-Pilot]

Who said I hate pilots? My family's livelyhood is provided by aviation of which there would be none without pilots. I wasn't blaiming them I just stated a statistic. Hopefully you read your training manuals and absorb the information better than you are showing here.

The 99% was not encompassing all aviation, just a certain sect and to explain what sect I mean would cause me to reveal. Caphece?

Yes, I "Caphece" (whatever that means, because it deffinatly isn't Italian), that there's no point in trying to discuss any further with you. Keep blaming 99% on human error, enjoy your own lie.

[787FOCAL]

Yes, I "Caphece" (whatever that means, because it deffinatly isn't Italian), that there's no point in trying to discuss any further with you. Keep blaming 99% on human error, enjoy your own lie.

It was just a typing error. :rolleyes:

I also did not say that I was for sure on that stat. Just thought I remembered hearing that. I don't book keep stats like that.

[Belgique]

The Air Safety Week Article mentioned by Matblack (page 45 post #895)
.
"The Unthrustworthy 777"
.
is available in its entirety here (http://tinyurl.com/yvxqqv)

It would seem, by inference, to make a TOGA Press a sensible thing to do - once faced with a nil responsive duo of any brand of 777 engine.

[Lazarus42]

Hi all...

First of all I'm stunned at the calm professionalism and precise, quick actions of the triple seven crew. A major incident averted and everyone got to go home for tea. The view out of the windows during the last few seconds must have been truly daunting. If we ever bump into each other, it's my round!

Now... This will be my first and last post.

I don't fly. Half an hour at the controls of a Piper Tomahawk, dangling from a paraglider at 50ft (was meant to be practising "ground handling"... whoops! ;) ) and a lifelong interest in aviation does not a pilot make. I just would like to say that as SLF ( Gotta love that phrase) I come here to learn. Just the day to day stuff flight and cabin crew take for granted as another day at the office fascinates me.

But with an incident like this (amongst others to be found in these forums) this is the best place for people who know what they are talking about to discuss what happened and what it means for crew, passengers and the industry as a whole.

I think you should have a "professional only" forum. It would keep the armchair pilots (like me :( ) from posting all those "I'm not a pilot but...." posts and keep the signal to noise ratio a bit higher than it currently is.

But please let us read it! I don't want to post but would hate to lose the insight and information contained herein. I've spent many a happy hour reading and learning here and would mourn it's loss.

A little knowledge can be a dangerous thing. But well informed passengers who know why they are told to put their seatbelt on and can't open the windows must surely help.

Laz

[787FOCAL]

The Air Safety Week Article mentioned by Matblack (page 45 post #895)
.
"The Unthrustworthy 777"
.
is available in its entirety here

It would seem, by inference, to make a TOGA Press a sensible thing to do - once faced with a nil responsive duo of any brand of 777 engine.

Different engine. Different control software.

[WatcherZero]

Lack of info being discussed on the last few pages in the thread so I thought I would bring you back up-to-date on the latest released info in the UK. To remind you of whats known so far.

*Plane was coming in on auto
*Power was lost in both engines
*Autopilot sent several requests for more engine power to the engines, no response.
*Cockpit warning for engine power shortfall to autopilot failed to sound.
*Pilots took manual control and set maximum throttle, again there was no response from the engines.
*Debris analysis showed that one engine had been working when hitting the ground and one hadnt due to the fact one engine only scooped up dirt while the other sucked it in.
*Both the APU and Ramjet had been deployed

[r011ingthunder]

"I been here way longer than you Mr. Just signed up in January 08
My other profile was signed up in 2000 and has 1000s of posts. "

And your point is?
I haven't spouted "statistics" like:
"Men always prepare for the worst and are pleasently happy when the worst does not happen. Females usually look for the best and are pissed when it does not happen.
or
"Last time I checked it looked to me that 99% were human error"

I may be new to the forum, and certainly my experience of it is limited to this thread, and I must say posts like yours are central to my diminishing evaluation of the content.

If I were to quote statistics, I would make sure of my sources, and quote them where possible, but at least make them based on fact!

"I also did not say that I was for sure on that stat. Just thought I remembered hearing that. I don't book keep stats like that."
If you quote a statistic which you "think you remember hearing" then it IS NOT A STATISTIC!

[shawk]

Are there any credible reports of unusual maintenance activity on the BA 777 fleet or unusual fuel quality analysis on aircraft refueled in China after the accident?

[787FOCAL]

My bad. Just for you, next time I will confirm first. :\

[WatcherZero]

no reports of unusual maintenance activity, the plane in question had had a full overhaul a month earlier. There was a report though im not sure of a 777 taking off from china last year that shortly after takeoff lost all mechanical and eletrical power for 40 seconds or so then it suddenly returned and the flight continued as normal, no cause was found.

[lesthegringo]

'Ramjet deployed......'

I like it. The warp drive probably didn't kick in though....

'The other engine didn't suck in dirt'......

X-Ray vision at work

99% of all people are caused by accidents.... Now that is more plausible....

Keep going, lads, this is better than TV. Just give me some time to go and get more popcorn, please

[787FOCAL]

99% of all people are caused by accidents.... Now that is more plausible....

LOL best all day. :}

[HotDog]

Lack of info in this thread so I thought I would bring you up-to-date on the latest released info in the UK.*Autopilot sent several requests for more engine power to the engines, no response.
*Cockpit warning for engine power shortfall to autopilot failed to sound.Debris analysis showed that one engine had been working when hitting the ground and one hadnt due to the fact one engine only scooped up dirt while the other sucked it in. *Both the APU and Ramjet had been deployed.

Thanks for bringing us up to date.:rolleyes:

Dear Jesus, where do these people come from?:{

[Out Of Trim]

WatcherZero

Thanks for that so-called update. :ugh: :confused: :ugh:.

You don't work for the AAIB then I take it...:rolleyes:

So it was coming in on Auto and deployed it's Roger Ramjet and sucked up the earth - I got confused right after Auto!

Jeez that was funny:}:}

[misd-agin]

http://www.pprune.org/forums/images/statusicon/post_new.gif Today, 13:20 #729 (http://www.pprune.org/forums/showpost.php?p=3848304&postcount=729) Seggy (http://www.pprune.org/forums/member.php?u=151001)
Instead of being 'just another number' I could order a Personal Title (http://www.pprune.org/ptorder/ptorder.htm) and help support PPRuNe

Join Date: Aug 2006
Location: New York, NY
Age: 25
Posts: 9


It is going to be interesting to see the FINAL accident investigation report. There is going to be a lot of 'politicing' going on behind the scenes with this one.

Great job to the flight and cabin crew.
Last edited by Seggy : Today at 13:35. Reason: typo
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Well, I find it interesting that you comment about the 'behind the scenes politicing' that will go on and then contribute to what can cause it... by praising people before the facts are known. :ugh: If the facts don't support the public praise it certainly puts the investigators in a tough spot, doesn't it?

U.S lead safety investigator - "we have to be careful how we handle this. The press has made a hero out of this guy." This after finding some unexplainable behavior during the investigation. Yes, they're aware of public sentiments and pressure.

The comments about 'speed reduced'(AAIB), 'stickshaker'(London Times), and 'dropped in from 10 feet'(pprune post allegedly quoting news report), could be spun to make a complete different story. Until the facts are released I think we should wait before we start cheering or pointing fingers.

None of us know what really happened. The investigators aren't talking. Give it time....

[EFHF]

From the AIP: 27L PAPI 420M in from THR, MEHT 65ft.

So, the PAPI (roughly in the middle of the touchdown zone, TDZ), is inset 420 metres from the painted threshold (not necessarily the end of the tarmac). The glidepath will "aim" at the same point, being calibrated to achieve this.
If with "glidepath" you also mean the ILS glidepath, this doesn't appear to be so for 27L according to the PATC (http://www.caa.co.uk/docs/64/DAP_ACD_PATC_London_Heathrow_Rwy_27L.pdf), the Aerodrome Chart (http://www.flyuklive.com/ukcharts/EGLL/egll-airport-chart.pdf) and the actual runway markings as visible from satellite pictures (http://maps.google.com/?ie=UTF8&t=h&om=0&ll=51.464402,-0.438756&spn=0.002239,0.005021&z=18).

The PACT lists the threshold altitude as 56 ft from the runway surface (as opposed to 65 ft for PAPI).
56 / tan(3º) = 1068,5 ft = 325,7 m

Also see the AC and the Google Maps picture. The PAPI line (the western white north-south oriented line drawn on the southern edge of the runway) is about 100 m from the eastern line which marks the position of the ILS GP antenna and aimpoint in relation to the runway). The PAPI line mark is at the start of the visual aiming point markings on the junction with taxiway Victor.

Not that this would make any difference to how much the aircraft fell short, because when flying manually in good weather you would aim more towards the PAPI line and touch down a little bit even after that with a good flare, but just to be really anal about the numbers.

[KaptinZZ]

Watcher Zero, where did this information come from?

You mention "published", but by whom and what was the source?

It is worthless unless the source is credible, and I'd have to suggest that the investigators wouldn't be releasing bits and pieces at this stage.

[UNCTUOUS]

It's likely that this paragraph from Belgique's linked article (post 940 (http://www.pprune.org/forums/showpost.php?p=3849310&postcount=940)) will be the operative issue:
.

"Overall, it's shades of the previous GE90 "rollback" and IFSD's (inflight shutdowns) from earlier days. The only difference was in those cases, it was in cruise and was caused by moisture freezing in the P3B and PS3 lines to the FADEC, and it was resolved by increasing the tubing diameters."
.

Methinks that frozen fuel pressure reference lines identically influencing each FADEC's outputs would stand the best chance of uniformly affecting both engines (for identical reasons - and perhaps related to Beijing's fuel quality and the amount of FSII icing inhibitor included in the fuel uplift being inadequate).
Those reference line thickness parameters are unlikely to differ overmuch between engine types.

[WatcherZero]

The AAIB had a press confrence and released their "preliminary findings" to the media.

[lesthegringo]

http://www.aaib.dft.gov.uk/latest_news/accident__heathrow_17_january_2008___initial_report.cfm

Funny that the AAIB have a press conference that gives details that confict with their official report. If they made a press release, a transcript would be available.

[Shore Guy]

Does anyone know if the fuel source in Bejing has yet been tested and any findings?

[HotDog]

Shore Guy,

ZBAA is the second busiest airport in Asia with some 1,100 movements/day. The fuel is international standard A1. I think you can forget the contamination theory. A lot of aircraft would have fallen out of the sky on January 17th, if that was the case.

[mocoman]

None of us know what really happened. The investigators aren't talking. Give it time....

Best Fuggin' post in 48 pages. I'm with you mate.....:ok:

[Danny]

Thread closed to due to unwieldy nature of such a large amount of amateur hypothesising interspread with some real knowledgeable nuggets.

Initial report out and new thread started. Hopefully we'll be able to keep the pretenders and dipsticks more at bay on that one. :rolleyes: