BA B777 Incident @ Heathrow (merged)

[404 Titan]

I too personally doubt fuel exhaustion or mismanagement but you don’t rule out investigating it. With the wind like what it was on the TAF I strongly suspect it could have been low level windshear though. A quick pulling of the QAR and the FDR and CVR will ultimately determine what went wrong.

[In trim]

No speculation......I'm happy to wait till the AAIB report.

I hate using LHR (operationally or as a passenger) for so many reasons........but there is no doubting the professionalism of all the emergency services, and of course the ATC'ers who, I have no doubt, did a fantastic job yesterday given the incident itself, and the immediate high workload in managing the diversions. Well done to all.

Regardless of the cause, it could so easily have been so much worse.

[Volume]

On most airliners, the RAT supplies AC power to the Emergency bus.On many airliner (i.e. all Airbus) the RAT supplies hydraulic power, not electric power.

[Aussie]

Well said mate. Good effort by the flight crews! Interesting to see and speculate once the facts are out.

[SB4200]

A minor point but one which highlights the depth of knowledge of some of these characters... Starvation and exhaustion are different things.

[anartificialhorizon]

From the BBC website....

Witnesses on board the plane said they only became aware of a problem just before the plane was due to land.


Passenger Jerome Ensinck said: "There was no indication that we were going to have a bad landing. When we hit the ground, it was extremely rough, but I've had rough landings before and I thought 'This is the roughest I've had'."


Antonio De Crescenzo, 52, from Naples in Italy, said: "We were coming in to land but the plane felt like it should have been taking off. The engines were roaring and then we landed and it was just banging.



Before you shoot me down in flames I know witnesses cannot be fully relied upon following an incident like this but from what nearly all are saying it would appear that at least one engine was operating prior to touching down. Nobody has said the aircraft went quiet, the lights went out or flickered which might suggest that the aircraft had lost electrical and or engine power.

This is going to be a very interesting investigation and I am intrigued to see what the AAIB report in their preliminary findings.

[Hoofharted]

Interesting to see and speculate once the facts are out


Whadya mean "when the facts are out". There has been more speculating, postulating, pontificating and d1ck waving on this thread than there oughta be at this point in time. Some people just can't wait to have a crack at other crew or point score amongst themselves on this site. :yuk:

[pip_kuruvilla]

Hey Danny
Just heard you on BBC 5live. Very wise of you to ask the general public to be more circumspect when commenting the pilot on his bravery. You might just be the first person to do so. Kudos to you!
- Philip

[HotDog]

Visual, your noble defence of the 777 commander would have benefited greatly from the use of a dictionary.

He is not only a superfluous operator

Superfluous adj.;

1./ Exceeding what is sufficient, extravagant, superabundant.

2./ Not needed or required, uncalled for, unnecessary.:E

[Bus429]

In keeping with a few other cool heads, I recommend we wait for the AAIB to report. I wrote to BBC 2's Newsnight programme last night to complain about the tendency to consult "experts" - how many of them are rated to fly or maintain the 777? - and the appalling speculation on the part of their "science" correspondent Susan Watts. She must have misconstrued some "valid" speculation and then spouted absolute b*ll*cks. I thought I knew how ILS worked; now I'm not so sure.

The crew did a good job, regardless of cause but we wait to see what put them in that situation (and I'm not implying anything!).

While not commenting directly on this incident, fuel starvation has been the cause of incidents and accidents and it has affected modern aircraft:

Gimli glider (Air Canada 767 in 1983- combination of technical failure and mismanagement)
Air Transat 231 in 2001 (maintenance error - failure to consult approved data during an engine change - compounded by crew's failure to consult FCOM when faced with the consequent leak from the right engine 5 days later).
Both classic examples of accident causation - the holes lining up - and there but for the grace of God...we are all susceptible.

[cowpatz]

Just a couple of observations as we arrived on 27R some 40 min or so after the 777 mishap on 27L.
There was convective activity in the area.
ATIS was giving either moderate or severe icing at FL090. I cant recall exactly which it was. Not sure if the 777 held prior to approach but engine icing may or may not be a factor.
There was a significant shear.
At 4000 ft on final approach the wind was bang on the snout at 50 kts with a surface wind at 220/8. I cant recall the 2000ft wind but at that point on the approach the tower advised that the surface wind was now 220/16 G32. That in itself is not significant but it did make for a rough ride and did require overiding the autothrottles with manual thrust application to maintain speed.

Without knowing any facts I would probably eliminate a low fuel state as this would have been acted upon sooner and ATC advised.

I have no idea what the spool up time on a large Trent eng is, but with the shear that was present at the time we arrived, it could have been easy to have ended up unspoole, and with a bit of negative shear thrown in the mix, it would explain the noise (attempting to spool up) and high nose attitude.

Engine icing may also be a possibility. Not sure if nacelle icing is auto or man on a 777 but if it was left off, and if the conditions around at the time of the 777 arrival were similar to those when we arrived, then it may be a factor. Not necessarily a total engine failure, but enough to affect either spool up time, or the amount of power available.

Just my .02 cents worth and only offered up for discussion and not in anyway an attempt to criticize the actions of the crew.

[HotDog]

Volume,

On many airliner (i.e. all Airbus) the RAT supplies hydraulic power, not electric power.

You are obviously not an Airbus Aerospace Engineer.

The A340 Rat supplies emergency hydraulic power which also drives a hydraulic motor generator which supplies emergency electrical power.

[QCM]

:D:D:D:ok::ok: Congratulations to the entire crew,if they read or not these lines...very well done :ok::ok::D:D:D

As one of your Prime Minister once (almost) said,in a difficult period of your History...
"Never in the history of BA was so much owed by so many to so few". W.C.

[ETOPS Jock]

Cowpatz

I guess you're a 74 driver.

Having flown both 74 & 77 the auto-throttles move helluva lot more aggressively on the 77, especially if the speed gets low.

At the end of the day, any landing you walk away from is a good one, and they all walked away from this one. Now we will wait for the real experts to offer their considered opinions in due course.

ETOPs

[Brian Abraham]

With some of the advice/opinions being offered here I'd be more inclined to seek this gentlemans advice. What say 411A, PJ2?
http://www.youtube.com/watch?v=n8L-ZZSc8JU

[PJ2]

From the B777 AOM:

The RAT can supply electrical and hydraulic power simultaneously. If the RAT is unable to maintain
RPM, the RAT generator electrical load is shed until RPM is satisfactory. Power for standby electrical
loads is provided by the main battery during deployment of the RAT and when RAT generator loads
are shed.
The RAT is deployed automatically if both AC transfer busses lose power in flight. The RAT can be
manually deployed by pushing the RAM AIR TURBINE switch on the overhead panel.

On some, but not all B767 installations, there is a hydraulically-driven motor-generator.

[vmo]

As a 777 cpt I am very interested to know what happened,
I don't have any speculations, sorry.
I know how I feel sometimes after a 10, 11 hr. flight, maybe a bad night sleep before departure, and then to experience major difficulties just before landing....no thanks.
I am very glad for the pilots to hear there are no fatalities; as events will be going through their head again and again, they won't have the extra burden of loss of lives and the emotional impact of that.

[Keg]

here has been more speculating, postulating, pontificating and d1ck waving on this thread...

You obviously haven't been reading the thread running on the main news forum on PPRUNE. Strewth, talk about people talking about things of which they have zero idea.

[XTRAHOLD]

To &&&, if under those conditions of wind and gust you don't add that speed on your VRef, I don't want to ride on any of your flights, that is if you are a pilot at all.

[Hooligan Bill]

Rather than a large flock of birds, how about a flock of large birds. Canada Geese and Swans have been identified in previous AAIB reports as potential hazards in the Heathrow area.

[PJ2]

Brian Abraham...love that piece...showed it everyone here, passed the url out to as many as I could - great, great comedy, and yes, I'd agree that some sources have this peculiar quality to them, but some sources just don't know what they don't know.

[cub71]

May I suggest you stop speculating and monitor this page instead:

http://www.aaib.dft.gov.uk/publications/special_bulletins.cfm

[PBL]

Could a gust at Vref in any way cause a double compressor stall?

PBL

[king surf]

The Press speculation on this incident beggars belief.They clearly display a total lack of knowledge of this industry.

[tonyflaire]

Just slightly off topic..but maybe now someone will look at FTL and realise an emergency at the end of a long duty, is a reality. How long will the CAA keep giving airlines, Level 1, 2 or 3 extentions? I know its not the case hear, but inflight rest on the flight deck or cabin needs looking at too.

PS. My feeling go out to all concerned at this difficult time. I think its great that everyone got out. Well done to all concerned.You can alway replace an airplane! I don't worry too much if the insurance companies lose out!

[DutchRoll]

I saw a couple of the "eyewitness" accounts on the news, and it seemed clear they had not the faintest idea of what they actually saw!

This is very much in keeping with the general unreliability/differing perspectives of eyewitnesses to an event which they see for only a few seconds. I'll eagerly await the enquiry!

[helldog]

Hi drag high power approach. You lose the power your just left with hi drag, how the hell do you even make it inside the airport fence? Regardless of what happened awesome job to get it down as they did....well done Nigel!

[Guy D'ageradar]

Lots of speculation here, but unlike any incident report that I have ever seen, all of them specify a SINGLE cause.

Chain of events anyone?

How about power loss / major bird strike FOLLOWED by windshear in a critical phase of flight. :eek:

Please feel free to add more.....that's what a rumour network's for! :E

Just my 2p.

[sandbank]

Surely someone somewhere must have video of this approach and landing? We asked BAA to allow us to set up a permanent outside-broadcast set up at LHR to show every take off and landing live on a dedicated broadcast/ cable or internet channel. ....They refused point blank!

[404 Titan]

Hoofharted

Even some experts in London are suggesting it could have been windshear. Aircraft at the time were apparently experience wind changes below 200ft with the associated variations in IAS. I personally haven’t experienced it in LHR but I have in HKG and NRT. Luckily for me we knew it was coming and it was positive windshear, not negative as it appears likely here. What I have experienced at LHR is wake turbulence below 200ft because of the 3nm separation they use there on final. I was flying an A340-600 and we were following a B747-400.

By the way, how do you think the investigators initially start the investigation? They use experience and evidence to deduce (speculate) the most likely cause so they can direct their resources in the most economic direction.

[hetfield]

@sandbank

Who is "we" ?

[XTRAHOLD]

To helldog, that is exactly my point. If you loose all power the only thing you have left is to trade speed for lift and you squeeze it out as skillfully as you can by pulling on the elevator and keeping those wings as level as possible, hopefully running out of lift just as you touch down. If that was the case and nobody knows yet, they did an awesome job as you never parctice that in the sim, just seat of your pants flying!

[A and C]

As an ATPL & Maintenance engineers licence holder I have seen the news reports and 14 pages above.

At the moment I could not say with any reliability what the cause of this incident was, about the only thing written above that I would agree with 100% is that we should wait for the AAIB report before speculating further.

However nothing that I say will stop the rubbish that is being spouted by the so called avition experts.

[anengineer]

10%: "I think all this speculation is disgraceful, everyone please shut up."
10%: "Cud it be maybe the pilut fell asleep and the wheels fell off ?"
TV News: "We are getting reports that the pilut fell asleep allowing the wings to fall off"
80%: "I think all this speculation is disgraceful, but.... <huge amount of speculation>"

This place never changes. :)

[BEagle]

Firstly, congratulations to the crew for making such a successful forced landing that everyone survived with only a few minor injuries reported. Indeed, some passengers didn’t even know they’d been in a crash. The evacuation appears to have been copybook; perhaps that alone fully vindicates the airline’s policy of cabin crew salary scales which encourage ‘career’, highly professional, cabin crew?

Regrettably, there has been a lot of nonsense posted on this website and sifting through the garbage has taken quite a time. Thanks to those who provided factual description of the forced landing, that alone has narrowed the possibilities. Drunken aussie pranskters and off-the-wall wild-ass-guesses haven’t helped.

PJ2, I think your line of investigation is very probably close to the mark. Has it yet been established whether the engines were at idle thrust – or had flamed out. In very gusty conditions, if the automatic throttle system (sorry, I don’t know the Boeing term) detects – for whatever reason – a significant excursion well above the target speed, how much authority does the system have and is the gain rate sufficient to command both engines to idle thrust at a rate which might be difficult for the crew to react to in the last few moments of a very long flight? If the engines were commanded to idle thrust at 400 ft in an unusual weather situation, how long does it take to take over manually and recover the situation in unpredictable, gusty conditions?

These are questions, NOT speculation.

Again, very many congratulations to the crew for their highly professional actions.

[sleeper]

Beagle:

B777's Thrustlevers move! Thank god for that.
As the PF's hand will be on the throttles, he/she will know if the autothrottle is powering back without looking at the instruments.
Muscle memory will give him/her ample warning. After that it is just a matter of stopping the levers coming back to idle and as thrust is allways relevant to powerlever angle it will stop decaying. If you need more thrust just push them back up. No big deal.

[CAPTBOB]

Dont worry, it's just management pilots having a crack at their minimum fuel policy. Note to self, continue to disregard company minimum fuel policy!

[CAPTBOB]

Dont worry, it's just management pilots having a crack at their minimum fuel policy. Note to self, continue to disregard company minimum fuel policy!

Not so much of a speed bird as a stuffed duck

[twistedenginestarter]

At least two witnesses - one a passenger - report the engines were racing or sounding like take-off. Why is everyone ignoring this?

Also:

Prime Minister Gordon Brown, who is on a visit to China, has praised 43-year-old pilot Peter Burkill's "professionalism" for managing to avert a major disaster.
As is most of these cases the flight crew didn't (couldn't) do anything that wasn't utterly straightforward ie choose a speed, keep flying and pray.

[TheOddOne]

Lots of speculation, it's a rumour site, after all!

However, one aspect is apparent already; the design of the various protected slope surfaces, runway Strip and Cleared and Graded Area (CGA), Runway End Safety Area (RESA) and other aerodrome criteria has in this case proven to be entirely adequate. These distances/dimensions have been arrived at over the years by expeience with other accidents and incidents (I personally recall the Continental B747 getting rather too close to the South Terminal roof at LGW). Have a look in CAP168 for a lovely diagram bringing all the surfaces together; it looks a bit like a sports stadium with the runway on the pitch.

Recently, ICAO recommended that RESA be increased from 90M to 240M, good call!

Although the CGA has a 'neck' 75M either side of the Centreline at the runway ends, the Strip is still 150M and the closest holding point must be 90M from the Centreline. These figures for a Code 4 Instrument runway, which is what 27L is, of course. In this case the a/c slewed as it changed from one surface to another but a vehicle or aircraft holding at NB1 would have been OK.

Another aspect of aerodrome design that no-one ever sees is protection for undercarriage running in the soft, encountering the edge of a runway or taxiway. An underground ramp is constructed at all transitions to allow wheels to ride up onto the hard, instead of the gear being wiped off by a vertical surface. Unfortunately the main gear in this case was already destroyed but it does appear that the noseleg, although compressed into the fuselage, might well have ridden up the ramp. This safety provision is known as 'Delethalisation'.

Now, Public Safety Zones, there's a whole new topic!!

TheOddOne

[Contacttower]

At least two witnesses - one a passenger - report the engines were racing or sounding like take-off. Why is everyone ignoring this?



Indeed, it simply doesn't add up with the 'aircraft lost power' theories and it does seem to rule out actual engine failure. Reading through the Times one witness thought the engines sounded like they were in reverse...uncommanded deployment of the thrust reverses perhaps?

It would explain both the 'roaring' and the 'loss of power'.

[Danny]

Once again, in order to try and quell some of the uninformed specualtors, engines losing thrust do not necessarily have to be "silent" or shut down! As long as they are unable to provide the commanded thrust or the necessary thrust to overcome the drag to maintain the flight profile then you have a significant problem.

So, would the speculators who have very little obvious idea of what is involved, please sit back and read rather than postulate with obvious lack of understanding! We need all the bandwidth we can get at the moment!

A Trent engine, even at idle power will sound like it is "roaring" if you are standing close enough! :rolleyes:

[NSEU]

The RAT is deployed automatically if both AC transfer busses lose power in flight. The RAT can be manually deployed by pushing the RAM AIR TURBINE switch on the overhead panel.

Actually, the 777 RAT has a 3rd way of deploying. It also deploys for low hydraulic pressure (the logic too extensive to list here). Since the RAT on a 777 provides both elec power and hydraulic power, it makes sense to have two sets of logic.

RAT deployment logic includes airspeed or groundspeed, air-ground, engine below idle, time delays. etc. Loss of power to the Left and Right Transfer (Electrical) Busses also autostarts the Auxilliary Power Unit.

The RAT deploys in 2 seconds after the logic has been satisfied, but will obviously take a few seconds to get up to full operating speed.

The 777 is most definitely Fly-By-Wire. Don't be fooled by the traditional-looking control wheels.

Re the flickering of lights.. If AC power changes sources in the air, there is a "break power transfer", so the lights might flicker. There may also be automatical loadshedding disturbing the electrical system.

Regards.
NSEU

P.S. I think a Malaysian Airlines 777 had an uncommanded thrust reduction (but I thought the manufacturer fixed that problem with new software).

[EFHF]

The next rumor from The Sun (http://thesun.co.uk/sol/homepage/news/article700633.ece) suggests some autopilot/autothrottle glitch and also alledges that a mayday was broadcast:
Insiders said inquiries were focusing on an unexplained “involuntary flight control command” initiated by the jet’s computer.

The on-board system is thought to have pulled the plane’s nose skywards as it began its descent.

At the same time, it is said to have throttled BACK the engines.

Only one other similar fault has ever been recorded - and resulted in a multiple-death crash 15 years ago.

It appears an alledgedly similar incident has happened to a B777 before in 1995 (summary (http://aviation-safety.net/database/record.php?id=20050801-1), full report (http://www.atsb.gov.au/publications/investigation_reports/2005/AAIR/aair200503722.aspx)) due to false accelerometers readings and failure detection logic.

This incident ending in a successful landing is not the "multiple-death crash 15 years ago" referenced by The Sun.

Just offering this to discussion, not in any way supporting or endorsing the theory. Instead I think at least the claim that emergency comms were initiated is not credible, because we should have heard this from a lot of other sources if it was true.

[gchriste]

I know I really shouldn't post, SLF sorry, but a few people have said about the supposed eye witness reports of engine roaring.

Seems people have said if the RAT was out (does not seem clear if it was or was not) it is bloody noisy. Could that account for the noise they may have heard?

[RoyHudd]

Single-engine failure? Low down, low thrust, gusty cross-wind, down-draught/windshear.....could be tricky for the A/THR and PF to handle. Might explain steep bank angle and noise from one engine. I know, I know, this shouldn't cause an undershoot of such proportions, and this is mere speculation. Hope fully all will be revealed from the FDR and CVR.

Well done, BA crew and emergency services. Quick and positive response.

[TheOddOne]

A couple of years ago it was proposed that the 27L/27R thresholds and aiming points be inset by around 500M to raise the approach slightly and reduce noise impact. 27R in particular has excess landing distance available over requirement for all types.

Perhaps the time has arrived to review this idea from a safety case point of view rather than an environmental one?

TheOddOne

[fox niner]

Single-engine failure? Low down, low thrust, gusty cross-wind, down-draught/windshear.....could be tricky for the A/THR and PF to handle. Might explain steep bank angle and noise from one engine. I know, I know, this shouldn't cause an undershoot of such proportions, and this is mere speculation. Hope fully all will be revealed from the FDR and CVR.


Nope. not true.

A single engine failure at that stage of flight is irrelevant. Even from a autopilot/autothrottle point of view.
I specifically remember being in the simulator for my conversion training to the B777, and the instructor gave me an engine failure at 500 feet, on short final. The autothrottle and autopilot were engaged, because the weather was Cat III. result? uneventful landing, autoland.
Conclusion: a single engine failure at 500 feet is more or less irrelevant, and will not make a whole lot of difference.

Also, a single engine failure will not any handling difficulties. The 777 is always in trim. As long as the airspeed remains the same before/after the single engine fails, the airplane is still in trim. there is an automatic trrim system installed. so no handling problems there. Furthermore, the autothrotlle is very "agressive" and will react firmly to the single engine not providing any thrust. It only needs to add about 7% N1 to compensate anyway on a 3 degree glidepath.

[interpreter]

The comment about Vref and adding extra for the conditions reminds me of my "hoary" old Lanc pilot who said that after a long flight into enemy territory - and don't forget only one pilot on the Lanc - if the weather was even slightly unstable it was "add 5 knots for the wife and 5 for each child"

He said he thanked himself for that reminder on several occasions. (I am not suggesting anybody does this and ignores the manual!)

What concerns me quite a little about this incident is that a PPL reported a steep rate of bank on late finals. That does not suggest engine failure but abnormal airflow i.e. shear, violent gusting etc. Any comments?

[twenty eight]

Do the CVR and the FDR continue to work on a 777 with the engines shutdown?

[jetnoise2007]

http://www.heathrowpictures.com/pictures/pictures.html

[N1]

Will this one count towards a CDA?

[choclit runway]

Hi all,

Lots of mention of windshear but not much about vortex wake. COULD explain a wing drop. Seen it many times from the tower though I would add that it SHOULD NOT cause an incident like this if the a/c was in all other ways flying normally.

In response to so many other posts; most of the reporting from the press, from what I've seen, has been absolute rot. With regards to all the speculation, sorry folks, human nature and you ain't gonna stop it. If you don't like it I suggest you wait on the AAIB website instead of sitting on a RUMOUR website.

Best wishes to all on board and ground personnel involved.

CR.

[pjs_fly]

...what are the normal approach speed and stall speed for a 777?

[RogerTangoFoxtrotIndigo]

Well, whatever the cause of the short landing it was a lucky escape for West London. Probably not a popular view on this forum but the appoaches over central / west london are simply insane for the amount of traffic that now uses LHR.

I'm not anti airport, 27L used to be my local runway when I worked in technical block A

[moosp]

A colleague of mine flew several profiles on the 777-200 sim this morning (the real one, please, not the MS version) failing various engines at 500 and 300 ft on the LHR 27L model. A failure of 2 engines between 500 and 300 feet, with an attempt to stretch the glide towards stall speed produced a touchdown at a similar point on the visual model as the BA aircraft.

All this proves is that the simulator software will produce this effect. It does not indicate that a double engine failure on a BA 777 in that environment will produce the same effect. However, for those of you who are professional pilots on B777 this may be of interest to you.

Like most of the professional pilots on this site, I despair of the ignorance of many posters.

Please ladies and gentlemen, if you are not a professional pilot with experience of flying a 777, restrict your posts to facts that you know, or facts that have been communicated to you. Ask as many questions as you like, and ppruners with appropriate experience will attempt, bandwith permitting, to give you answers.

If you post rubbish, you will be judged and classed by professional pilots as rubbish.

[fox niner]

the RAT was deployed. here is the picture:

http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm15.jpg

So therefore it was a double engine flame out.....I guess. And that seems more likely than windshear. Specifically because the RAT is deployed.

Do the CVR and the FDR continue to work on a 777 with the engines shutdown?
Today 11:36


The CVR and FDR will operate even if both engines are failed/not operating, if the airplane is airborne.

[Danny]

Jetnoise2007's pictures provide some interesting views of the engines:

Left engine: http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm3_small.jpg (http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm3.jpg) Right engine: http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm20_small.jpg (http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm20.jpg)

No doubt those with better analytical skills will jump in here but it looks from the damage to the fan blades as though Left engine was producing some rotation when it ate the dirt whilst the right engine fan blades appear to be relatively undamaged.

[Buzz Lightyear]

After being told to turn off mobiles, laptops and all other electrical equipment due to interference with the aircraft controls. Could this be a ground based outside influence?

An "electronic storm" or whatever the geeks call it?

If there is fuel still on the aircraft, as reported by the beeb yesterday (although with one main gear ripped off and the other stuffed through the trailing edge I cant believe there wouldnt be a leak with potential fire risk??)
I cant think of anything failure-wise that would end up with a total loss of power.

[BHenderson]

Nobody seems to have mentioned the landing gear.

News report paraphrase: 'The landing gear deployed very late.'

-Uninformed speculation hat on

Could this not suggest that problems were occuring before the normal time for gear extension? 1500ft? Or do the 777 hydraulic systems have enough accumulator pressure to raise the landing gear, assuming it is raised hydraulically?

[sky9]

Statement from the AAIB website today:-
http://www.aaib.dft.gov.uk/latest_news/accident__heathrow_17_january_2008.cfm

[Permafrost_ATPL]

If anybody has accident investigation experience, please take a look at the pics in the earlier post (http://www.heathrowpictures.com/pictures/pictures.html)

Maybe I'm seeing things that aren't there, but... It looks like the blades of the first fan on the number 1 engine are all missing their tips. That's not the case on the number 2. Now, the cowling on number 1 seems to have suffered more damage that the cowling on number 2 (hard to say with the mud). So number 2 could have been spinning but the blades suffered no damage due to intact (ish) cowling. But could someone with adequate knowledge tell me whether the blade damage on number 1 could have occured with just a windmilling fan or would you expect some level of thrust to be present? If you have an opinion, please state your background so we have some idea about the depth of your knowledge.

On a side note, can you confirm that the RAT on the 777 would only deploy for double engine failure (as opposed to single)? The answer is probably in a previous post but with all the "server is too busy" hits, I don't have the patience to look :)

Cheers

P

[Clarence Oveur]

the RAT was deployed.
I am not sure you can conclude that the RAT was deployed from that picture. That the RAT is visible could be due to damage to the surrounding structure. The RAT doesn't appear to be damaged either, although the picture resolution makes details difficult to see.

With regards to the apparent difference in engine damage, as the RH MLG appears to have detached completely, while the LH did not, there would probably have been some difference in the ground clearance, or lack of, between the two engines.

[cowpatz]

Does anyone know what spec Av fuel is uplifted out of Bejing?
The temps enroute were very low with -73 degrees OAT at around 35,000 ft.
Our fuel temp got as low as -43 degrees C but we had Jet A1. Would have been a different story with straight Jet A.
The 777 was relatively lightly loaded and would have climbed to a higher alt and more quickly and cold soaked for longer. Just wondering if the power loss (if indeed there was one) could be related to fuel icing or more probably fuel waxing. Any fuel flow restriction would not be so apparent at low thrust settings, as in the descent, but may have become an issue when power was applied during the later arrival stage. This may have led to a total or partial engine failures.

Pure speculation I know. Just tossing around ideas.

[GAS guy]

...and this includes any other low post Ppruners that think they have the right to tell us that we shouldn't discuss this matter -- until it has been fully investigated. I agree with them. The speculation in here such as "The B777 is NOT fly-by-wire" and other dross is stomach-turning. If you have no clue about airliners, fly-by-wire, gliding, how much noise an engine makes with power on or off, stalling, AoA, RATs, windshear, fuel policies, etc etc etc, then why not just wait for the facts? ...and save the bandwidth.

[Skylion]

Look at the flaps. Correct landing settings?

[llondel]

To put possible causes to one side for a moment, at what point do they attempt to recover the baggage from the hold (and presumably the cabin)? Obviously it's not a trivial thing to unload, and they won't want to disturb the evidence, but there are presumably pax from the flight stuck away from home with nothing that they weren't carrying in their pockets (although I'd guess that BA will be taking care of them). Obviously if there had been a fire then there probably wouldn't be enough to recover, but it's only been slightly squished in this case.

Has the man with the pot of white paint been to visit yet?

[Feathers McGraw]

Just looked at the pictures at http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm20.jpg and http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm3.jpg

Does anyone think they look like they were rotating at impact?

The fan blades look practically undamaged....

Well scratch that for the No 1 engine, clearly I wasn't looking hard enough!

<fx: embarrassed cough>

Shuffles away....

[fox niner]

I am not sure you can conclude that the RAT was deployed from that picture. That the RAT is visible could be due to damage to the surrounding structure.

Well, you could be right there capt. Oveur. But it looks like a deployed RAT so chances are it is a deployed RAT. Seems more plausible than windshear. But in all fairness, the structure around it is quite messed up.
-----------------------------------------------------------
Fuel on the 777:


Does anyone know what spec Av fuel is uplifted out of Bejing?
The temps enroute were very low with -73 degrees OAT at around 35,000 ft.
Our fuel temp got as low as -43 degrees C but we had Jet A1. Would have been a different story with straight Jet A.
The 777 was relatively lightly loaded and would have climbed to a higher alt and more quickly and cold soaked for longer.

The 777 is not prone to fuel icing. the fuel tanks are positioned in the wings in such a way that the OAT can not "reach" the fuel and cool it down as much.

I have not seen a colder fuel temperature than around -30 degrees C on the B777, also overflying siberia. A 747 is much more affected by fuel cooling.
In China we get uplifted with jet A1 or TC1. (russian grade)

Alright. I'll be cleaning out the shed for a couple of hours. See you guys later this evening.

[aviat179]

Several eye witness reports from passengers onboard the aircraft suggest that they could hear louder than normal engine noise on the approach and a higher deck angle sensation than they are used to; so why are people coming to the conclusion the aircraft suffered a double engine failure. The short video of the a/c's approach confirms it was at an unusually high angle of attack, the approach path flown is consistent with the escape manoeuvre to be executed when encountering windshear. Based upon the facts, the two most likely scenarios which caused the a/c to land short are microburst or wake vortices encounter.

[vanman]

If the reports that there were no PAs made from the flightdeck crew after the aircraft had come to a halt, and that the evacuation was Cabin Crew initiated, are true (which I hope prove to be false) then there was clearly some failing in the cockpit. Whilst I am loathed to criticise, clearly either a call for normal operations or a call to evacuate should have been made.

Could some sort of static pressure blockage have led to erroneous (increasing) airspeed indications on the approach?

I would agree that it looks like the number 1 engine appears to have been rotating, whilst the number 2 blades look suspiciously intact.

What scares me is that these aircraft fly (up to) 180 minutes from a diversion at times. If this aircraft did suffer a double engine failure I would imagine this would have been immediately reduced to 60 minutes (or less). Possibly even the fleet would be grounded.

Anyone know whether the 777s are still flying today and, if so, what restrictions have been placed upon them?

[sevenstrokeroll]

such a long flight, was there an international relief officer?

[phil gollin]

Latest Channel 4 (i.e. ITN) SPECULATION was that water contamination was a POSSIBILITY. It is also reporting (seemingly as a fact ?) that both engines failed (?????)

My main point is, however, that whilst idle speculation and praising or blaiming of individuals or companies it is a natuaral outcome of the lack of information.

There is no possible way that any industry can keep the media, and especially the 24-hours per day TV outlets content. However, NOT giving out basic facts and known non-controversial facts is really only basic PR. The fact that whilst the BBC 1 o'clock news at about 1.15 yesterday (i.e. half-an-hour after the event) was stating that both engines had failed, but that since then no further non-controversial facts have been released merely gives rise to speculation (and even the 2 engine failure has not been really confirmed)..

Someone further up the thread posted something like "non-serious crash, no one dead" which is very naive. First it was a very serious crash, and secondly it happened in an area which was always going to attract attention.

Eye witnesses are notoriously unreliable (let alone imposters). It would seem that the range of comments from those that wished to be interviewed ranged from "very rough, we feel lucky to be alive" through to " rough landing, we only knew how rough when the oxygen masks (and some panels) came down".

These things get people watching news programmes and buying newspapers - with BA and BAA not giving out basic information the media has to do something (however despicable others might feel about that). All BA/BAA had to do was try to give out CONTROLLED information and time it for main news reports and newspaper print runs. Pop star publicists can do this, but somehow huge multi-million pound companies can't be bothered.

No one expects a detailed listing of every possibility, but basic information with timetables of likely, but not guaranteed actions, at least ties journalists down to limiting their speculation.

-----

As an aside I am very surprised that with all the enthusiasts around the airport there are no copies of tower voice converstaions or videos of the landing - maybe the yucky weather had them all in the local chippies.

.

[Doctor Cruces]

Speculation is going to be rife after this incident, until the AAIB report comes out. However, having had it straight from the horses mouth on the radio 4 news last night, we can rule out human error in this case.

David Learmount clearly stated on the five o'clock news that "British Airways pilots don't make mistakes" and then on the six o'clock news "It definately was not error.

Did I miss the publication of the very rapid AAIB report?

How come every time this bloke makes a statement on TV or radio his Kn*b quotient increases in direct proportion to the length of his speach?

Doc C

[bushbolox]

Danny,

I think you got up too early. Next time you do a walk round on a windy day watch the N1 baldes turn. Even better watch an engine wind down on a windy day. N1 blades have rotation.
Failed engine + fwd speed + relative wind = rotation but only drag not thrust.
Left engine was up wind .

[Hermano Lobo]

A FADEC problem ?
http://en.wikipedia.org/wiki/FADEC

Rarely is an incident like this down to just one thing. It is usually a
combination of events all happening at the wrong time.

Is it possible that when the pilot added thrust input the engines dropped
into ground idle ? With the engines spooled down, regaining thrust could seem like forever considering how close they were to landing.

There is also an indication of a greater problem of power loss.
Could this have caused a default to idle ? This would be an area
for computer expertise. With 1,000 + B777's sold it would prove
embarrassing in there was a problem with the type ?

A great piloting feat !

[llondel]

Skylion:
Look at the flaps. Correct landing settings?

You missed the bit on the end: "... for the circumstances". When we know the circumstances we'll know whether the flap position was reasonable.

Vanman:
If the reports that there were no PAs made from the flightdeck crew after the aircraft had come to a halt, and that the evacuation was Cabin Crew initiated, are true (which I hope prove to be false) then there was clearly some failing in the cockpit. Whilst I am loathed to criticise, clearly either a call for normal operations or a call to evacuate should have been made.

How do you know the flight crew didn't attempt to communicate with the cabin? Depending on the nature of the electrical failure and subseqent impact damage, it might not have worked. Or they were too busy with whatever shutdown procedures were left to do. Why shouldn't the senior cabin crew have authority to evacuate if they can't get through to the flight deck (who could have been unconscious/dead at that point), given that the aircraft was stationary, unlikely to move, and might yet catch fire. Best to get everyone out.

[scroggs]

Several eye witness reports from passengers onboard the aircraft suggest that they could hear louder than normal engine noise on the approach and a higher deck angle sensation than they are used to; so why are people coming to the conclusion the aircraft suffered a double engine failure. The short video of the a/c's approach confirms it was at an unusually high angle of attack, the approach path flown is consistent with the escape manoeuvre to be executed when encountering windshear. Based upon the facts, the two most likely scenarios which caused the a/c to land short are microburst or wake vortices encounter.

You've posted this theory several times, yet there is no evidence to support it. Video evidence posted on this thread shows the approach to be slow, stable, with a high (but not excessive) AoA. It is most certainly not consistent with a windshear go-round manoevre. Microburst, to my knowledge, has never been reported in UK. Some windshear may have been possible in the weather conditions pertaining (which have been reported several times in this thread, with a surface wind of around 220/14, varying in direction), but not of the scale necessary to bring a B777 down. As far as I am aware, no large airliner has ever been brought down by windshear in UK.

[SeaEagle]

I’m extremely happy that no one was badly hurt or killed and that the company came out in support of the air crew. The crew did a good job of the dead stick landing, but has the possibility that the fuel line were contaminated with AIR been considered?

[HappyFran]

I have no wish to speculate but it would appear that if Mike Walsh unreseveredly praises the Flight Crew, and have his PTR bods know the most first hand information then very probably the flight crew did indeed to an incredable job of get the aircraft down onto the best possible peice of ground.

I am only a PPl just staring out on the path to a commercial career but it does make me feel incredible proud to be entering a profession with such amazing proffesionals.

It seems that many people running airlines consider pilots as glorified bus drivers / minders and treat them accordingly. This incident I hope will make many of these people realise just why they are there and what an amazing job the can do when called upon.

[You Gimboid]

I haven't posted in more than two years but i can't hold back in the face of all this cr@p.

I can't believe that posters on this thread will slag off the "ignorant media" while tolerating the absolute tripe that is being written on this thread.

As you know the site has been swamped with journos trying to get an inside track from the "knowledgable, professional pilots" on this forum. With a few notable exceptions we have proved that we are behaving as anything but.

We can speculate for ever until the facts are made public. Until then, shut the hell up and let the professionals do their job of finding out what went wrong, how it happened, and what we can learn from the whole episode.

I apologise to those professionals who have enlightened us somewhat with their informed speculation, but as a BA 777 pilot based at Heathrow, I can barely stand by to read all the utter tosh that passes for "pilots'" comments in this thread.

[speedbird458]

Is it standard Operating Proceedure to do an APU start on BA in the air?

Thought they normally did it on taxi in? Unless you have a problem that is

The Apu door is open on the tail!!
The APU will Autostart for the following:

Aircraft in Air
Loss of power from BOTH transfer busesNot sure about the pictures of the RAT, it could of been dislodged post impact as there was lots of big bits falling off in that area
But that can be deployed manually or Auto

In Auto it will deploy for the Following

Aircraft in Air
Loss of power from BOTH Transfer BusesThese are both Gotchas for maintenance, if you jack the aircraft and you remove the power you get all sorts happening in the hangar if you dont pull CBs or guard the Rat area.!!!

So loss of Both main AC power sources then?...Both IDGs...or engines?

Cannaee get ane more power Capt'n...Never mind Scotty we are goin for a landin!!:sad:

If you aint got Airspeed theres only AoA...more of it..till Stall..Re: G-ARPI Trident in Staines

[The Sandman]

From the video - VERY high deck angle on short final. If the engines had flamed out earlier and were restarted following significant height/speed loss that would explain high power setting in attempt to recover airspeed from backside of the power curve. If one engine came back on speed first and power applied to it first that could explain the high bank reported.

[speedbird458]

Is it Standard oOperating Procedure to start the APU in the air at BA?
Thought they normally started the APU on the Ground at taxi in?
The APU door is open on the back end!

The APU will AUTO start for the following :
Aircraft in Air mode
Loss of both AC transfer busesIt Takes Approx 30 to 40 secs for the APU to start and the door to deploy before you get power generation avail

As regards the RAT, not sure if it was deployed or has been ripped from its housing on impact but it will deploy and provide basic generation of power through Hyds for Flight controls and CAPTs panel
RAT willl deploy with the following:
Aircraft in Air mode
Loss of both transfer buses for 15 secsSo NO AC power from either IDG then!..?? Both idgs go bang...unlikely
Both engines...even unliklier...or a combo one Eng and other IDG?

UNLUCKY

[fuel2noise]

Just how much fuel was in the tanks on coming to rest? Some or none?

Plenty of aircraft have come to grief in similar circumstances due to insufficient fuel remaining. Any rumours?

[henrypottinger]

fuel starvation.
No way, not a western airline anyway, not without a mayday call from one of the 3 or 4 crew members.

If that RAT was deployed as a result of whatever occurred, then whatever was the reason it was not a pretty one...would have been interesting to see the EICAS messages @ 100'!

RAT deployment:
• both engines are failed and center system pressure is low, or
• both AC transfer busses are unpowered, or
• all three hydraulic system pressures are low.

well done crew for keeping those wings level.

[EXLEFTSEAT]

This seems to be a very fortunate ending to an otherwise potentially
tragic scenario. I for one am extremely happy about the outcome.
For anyone who remembers the Etihad A-340 accident a couple of
months ago, when that aircraft basically broke apart on the ground,
with a little help, granted that, I would want you to consider the following. Someone in that threat wondered, what would happen to the A-340 if she had a hard landing. Of course we don't know and hopefully never find out, but, well, this B-777 did have sort of a hard landing, or?
Actually it fell out of the sky, and it's still in one piece. I flew my last bird 25 years ago, a wonderful and indestructable 727, but I am forever a Boeing fan. And yesterday's incident and the positive outcome is another reason why. You will have a hard time to get me into an Airbus. Wonder, how the new carbon fiber based birds will hold up in such circumstances. Again, happy everyone came out alive without serious injuries. Now you guys can go on with your theories:)

[EyesFront]

No causal speculation here... :)

I just want to say how impressed I am with the way that the airframe survived the impact. After losing that much energy in so short a distance, it's extraordinary that the occupants could just get up and walk out of the aircraft. From the published passenger accounts, they don't even seem to have adopted the brace position. Incredible!

[Lost in Saigon]

There is absolutely no doubt that these engines were rotating. As they would whether or not they were operating.

Only a proper investigation will determine how much power they were producing during the final moments.

http://i2.photobucket.com/albums/y17/msowsun/b93a730e.jpg
http://i2.photobucket.com/albums/y17/msowsun/65745b1c.jpg
http://i2.photobucket.com/albums/y17/msowsun/95a0ba34.jpg

[powerset]

This is why most professional pilots stay well clear of this forum. And to think that the press report from here, talk about the blind leading the blind!.

AAIB report tomorrow, they are the best in the world, why don't we let them get on with it. Todays peking flight is delayed on the ground due mandatory fuel quality check. What does that mean? Who knows.

[samuelwmartin]

What's the point in everyone speculating?!?! And then arguing about it and how unlikely or likely it is that what they say is what happened/didn't happen?!

Why can't everyonel just wait until the initial report by the AAIB comes out?

Everyone on here is just adding to the confusion and rumours which is unneccessary I think, and probably fuelling the media's own varying rumours.

[MostlyHarmless]

To me, one of those was spinning a lot faster than the other when it ate dirt...

[toro]

Vanman,

with reference to your comments hoping that cabincrew did not initiate evacuation I can assure you that in the right circumstances that it is correct for them to do so if.....???? "the aircraft is stopped and the situation deemed catastrophic", eg broken airframe, etc.

As I did emergency training recently in the cabincrew 777 sim (although fly the 747) with cabincrew I assure you this is NOT speculation but fact, and by all accounts the cabincrew did an amazing job as well.

Also from other forums, news feeds etc, comments etc I can also assure all of you that BA pilots are NOT praising themselves as being better at all and having worked in other airlines around the world I know that most of us would have performed equally as well, I gave up on pprune some time ago with the constant undervaluing/flaming of pilots (particularly BA) and hope that this incident underlines why we are paid what we are and the reason (albeit very rare) why we should be valued.

Oh and yes it would seem like all the ground based services performed in an excellent manner as well and I wish to add my thanks to them.

Thanks thats all.....

[lomapaseo]

I appreciate the learning from the experts here on how the B777 systems work and interact.

I also appreciate all who ask relevant question before speculating through more than one link in a causal chain.

Be mindful of reading post crash fan blade damage that you must consider more than what your eye sees in a single photo.

In order to cause significant fan damage due to crash impact you must have both high RPM and significant fan case crushing against the blades.

There are distinct differences to be interpreted between high RPM and low RPM ground impact fan damage as well as distinct differences between ground and an inflight damage of the fan.

I suspect that most people observing these photos would not be able to tell the difference (whether it was inflight or due to ground impact). However I do expect that the answer is already known to those at the scene, so I'll not speculate further without their comments.

[dns]

I can't believe that posters on this thread will slag off the "ignorant media" while tolerating the absolute tripe that is being written on this thread.

The difference is that we are having a casual discussion here, we are not standing up in front of the TV camears and claiming to know what we're talking about.

Personally I'm quite enjoying the speculation and debate. I'm only PPL holder with ambitions to go commercial, but I'm learning a lot from this thread so I'd like to see it continue.

If you are a 777 pilot, please by all means join the discussion and add your professional opinon. If you don't see the point, then why are you here reading this at all?

[Time Traveller]

No1 eng certainly was turning on impact, but I would expect far more damage to the fan casing if it was at, or anywhere near G/A power when it got fed LHRs finest turf.

[samuelwmartin]

Crash Pilot 30 Seconds From Disaster

Updated:14:19, Friday January 18, 2008
<H2>The pilot of a BA jet that crash-landed at Heathrow airport had just 30 seconds to save his passengers, Sky sources say.

</H2>http://static.sky.com/images/pictures/1634582.jpg Pilot Peter Burkhill

Captain Peter Burkill only discovered that his Boeing 777 had lost power when he was 500ft above London's rooftops.
He tried to apply more thrust as the plane sank dangerously low on its approach to one of the world's busiest airports.
But the engines failed to respond, leaving him with 30 seconds to decide how to handle the crisis.
Capt Burkill was forced to the land the jet carrying 136 passengers several hundred feet short of the runway

Pilots' union Balpa said Capt Burkill and his first officer John Coward had gone out for "a quiet curry" after the landing and were "embarrassed" by media coverage.

The Professional Pilots' Rumour Network website was also full of compliments from fellow pilots.
"I am only just staring out on the path to a commercial career but it does make me feel incredible proud to be entering a profession with such amazing professionals," HappyFran wrote.

[Contacttower]

If you look really closely at the short clip on Youtube of it coming in you can just make out some sort of trail (it might just be poor quality recording) coming from the left engine. Eye witness Robert Hardman writing in the Daily Mail reports that as the plane came to a halt flames were coming from the port engine which subsequently subsided. Something do with the reported lack of thrust perhaps?

[John Boeman]

My favorite post so far (back at No.218):
Chronic Snoozer
In the fullness of time the causes will be revealed. If it was a birdstrike, it must have been some flock of birds.

In the meantime it is sobering to think that a modern airliner operated by a first world airline could end up like this.

As a pilot - it reminds us that it can happen anytime, to anyone.
As a pax - reinforces the importance of listening to the safety announcements and reading the emergency card in your seatback pocket.

N1, your post No.277, I'm amazed (but not surprised) you went to the trouble of getting a new name for that one. ;)

[gatbusdriver]

I hope they had a skinfull as well.

I would certainly be in need of a few after that day at work.

As for speculation.........nothing wrong with it, we read through the dross. I of course wouldn't want to speculate. I certainly have my thoughts on the matter....something to do with aliens.

[rossma]

thought you might like this comment from the times website -

http://www.timesonline.co.uk/tol/news/uk/article3209055.ece#cid=OTC-RSS&attr=797084



ITs fortunate everyone was unhurt. THe boeing 777 is the safest aircraft in the aviation bussiness. IT was lucky that it was the boeing 777 that this happened to, if it had happened to any other aircraft then it would of been alot worse. If the pilot had not landed on the grass it could of been much more catastrophic due to the increased sink rate. A dual engine failure is extremely unusual. Seeing as this was a british airliner serviced in england it may of been possible that the service technicians had not been strictly following boeings exact maintainence requirements and may of adapted there own methods with boeing reccomendations. After all the boeing 777 was designed entirely on computers and was manafactured in america. In the united kingdom people in mechanical occupations generally seem to make quite alot of mistakes. Failure is not an option in aviation servicing and technicians. I've noticed that there are quite alot of bodgers and slackers in the united kingdom.

mike, london,

[ketchup]

http://www.big-boards.com/board/569/

[anotherthing]

As usual there is so much speculation when the facts are still to come in.

Typically, the ‘experts’ are deriding the PPLs etc for lack of knowledge yet go on themselves to speculate that the flight crew did a brilliant job to enable people to walk away (relatively) unharmed.

How is that in itself not speculation? Do we know it was not crew error? (I seriously doubt it was, but none of us know).

As for the ‘heroics’ of the flight crew, if (speculation now it is as it seems and was a major loss of power (however that was brought about) at a very late stage of the approach, what exactly dud the crew do that was heroic? It seems (more speculation, based on lack of notice to ATC and to the Cabin Crew) that this was a last minute event, in which case the A/C would have been stable beforehand. What exactly, apart from being very frightened, could the flight crew have done with a dead stick and only seconds to touch down?

Everyone walked away, which could have been fortune more than skill; huge kudos to the Cabin Crew who it seems were as much in the dark as the passengers and ATC, yet managed to very quickly and safely evacuate the aircraft. Considering that they seem to have had no warning until the aircraft ploughed in, they did exceptionally well.:ok:

[Gipsy Queen]

Have to agree, You Gimbold.

Plane lands short

Few minor injuries

PPRuNE GOES INTO MELT-DOWN!!!!

Danny, we need more thrust - it's easier to get on the horn into O'Hare than to penetrate the server this morning!:D

[derekl]

A simple question: given a Boeing 777 that made a 'good' landing, but not actually a 'great' landing, how is the aircraft removed from the threshold of 27L?. Will it be broken up in situ, or are there enormous cranes and trucks for such eventualities?

Just curious as to how you deal with this.

[Weggy]

"I've heard and read some wonderful speculation this afternoon. Who are these "experts" that keep getting drafted in? I worry that I may be missing out on a profitable niche as a self-appointed expert in something."

Reminds me of the Thames Whale incident last year, when Sky bought their expert into the studio - a carp fisherman! :ugh:

[dns]

Anyone wondered who the first officers were on the BA038? The captain has received a lot of praise in the media, but there has been no mention of the other 2 pilots, each of whom is as likely as the captain to have been handling the jet at the time. So far I've not even heard their names mentioned... Just a thought...

[rolling20]

The focus of the investigation into the cause of the Heathrow crash turned today to the aeroplane's electrics after it was revealed that Boeing aircraft have a history of onboard fires causing power failure.

"Boeing 777s have been involved in at least 12 serious incidents when electrical systems have overheated, it has been reported.

On four occassions "major damage" was caused to power panels on at least four occassions, it has been reported.

......It emerged today that the Department for Transport's Air Accidents Investigation Branch, which is carrying out the inquiry, warned about electrical overheating on the 777 in a report published last April.

It followed an accident in February when a pilot on a United Airlines 777 abandoned a take-off after it lost one of its main power control units — known as a bus. "


Im surprised this incident wasnt referred to before with regard to the BA777.
It may be a wider problem, i wonder if grounding of the fleet world-wide will occur?
Be thankful it was on short final and not out over the Atlantic. If the UAL incident had occurred at rotate from Heathrow..well, lets not go there.

Well done to the Capatin and crew.

[Memetic]

Captain Peter Burkill is due to be live on Sky at 16:00 UK time. (According to scrolling headsines banner.)

A clear indication that the powers that be and BA are confident they have a good idea of the cause and that the pilots and crew did a demonstrably good job.

[Monkeeeey]

'Quiet Curry' thats one you will never forget also a great way to mask the sweaty patches :-)

Any time now the media will start finding crazy links as to why it happened....

"On an Al Jazeera website today a reporter has witnessed a video of Alqieda leaders confirming they have infact invented a weather machine, osama himself created microbursts and is claiming the incident as his. They went on to say that with this new device of terror we will soak the infadels until they can take no more. The US responded quickly with a stern message...yes we have a weather making machine of our own, 150 megatons soon to come your way...better get that suncream out."

[flipperb]

Let me preface this by acknowledging that I'm neither a pilot nor a regular on PPRuNe. I'm an aviation enthusiast who came here for the first time today to see what was being discussed.

It's worth noting that I found my way here because the Wikipedia page for BA38 now includes a link to this discussion forum - this is, no doubt, the reason for the heavy traffic that's causing server overload. Somebody might want to edit the article to remove that link, but I'll leave that up to PPRuNe regulars to decide.

Despite my novice background, I'm quite confident in stating that the RAT could not have been deployed prior to the landing. Had it been deployed, it certainly would have sheared off during the roll-out (slide-out?) on the turf. There's simply no way that the RAT was able to withstand the friction that tore away the MLG.

Further, if you look at the previously posted photo of the RAT, it's obvious that the fuselage damage around that area would have left the RAT exposed. Even its final position suggests that it "fell" out of its stowed position late in the sequence of events.

I commend the highly competent crew for putting this bird down safely, and I'll also add my praise to Boeing for designing an aircraft that is not only fail-safe (evidenced by over a decade without a fatality - what other commercial craft can make that claim?), but also remarkably rugged.

[CXL1011]

I picked up on Sky News this afternoon the crew had been interviewed yesterday evening for three or four hours. Given the well known accuracy associated with media reporting of anything vaguely to do with aviation, this could be taken with a pinch of salt. However, though I am long retired, and may be somewhat out of date with matters pertaining today, I seem to recall recommendations from IFALPA about not submitting to post accident interviews until sufficient rest/recovery time has been allowed (usually overnight), and to be accompanied by suitable representation. I trust the pilots' association was on their case.

[G-CPTN]

Heads up - BBC Radio Five imminent:-
Interview with BA038 pilot expected any time soon (16.00 UTC).

http://www.bbc.co.uk/fivelive/ - there is a 'listen again' feature (see 'Drive') if you missed it - though he never gave any details of the event.

[venkoj]

Anyone wondered who the first officers were on the BA038? The captain has received a lot of praise in the media, but there has been no mention of the other 2 pilots, each of whom is as likely as the captain to have been handling the jet at the time. So far I've not even heard their names mentioned... Just a thought...

I remember the name John Coward being mentioned as the FO. I presume most of the hype has been around the captain as the majority of people would presume that he, as the man in overall charge of the aircraft, was in control during the landing.

But then as we know FOs are often handed the responsibility of landing in order to gain experience. Following all we have heard so far (mostly unconfirmed stories of course) that the events unfolded so quickly and unexpectedly, I wouldn't even be surprised if the FO was PIC on landing and the captain didn't have time to take over control of the a/c....

[brabazon]

Flgiht crew live on tv now.....

[Mechaniker]

SFo was PF

[dns]

I wouldn't even be surprised if the FO was PIC on landing and the captain didn't have time to take over control of the a/c....

Captain wouldn't have necessarily taken the controls anyway. If my understanding is correct (I'm found flying at the other end of BAs jets) in an emergency situation the guy/girl in the right hand seat handles the flying and the captain manages the situation. In normal conditions the captain and F/O complete equal numbers of landings, the only exception is in a strong crosswind or autoland when the captain is always handling.

[RiSq]

So the limelight went to the Captain, and as many had expected the FO was at the controls, so he is the main man. Expect the press to target the hell out of him now.

[roll_over]

So what was more nerve racking, landing the plane or talking to the world's media?:}

[Tigs2]

The Captain has just made a statement on the news. He praised his First Officer John Coward ? Howard?(could be Towers, I can't make it out) who was the handling pilot at the time. He said he was fortunate to have such an excellent team, and of particular note the CSD who initiated the evacuation calmly and professionally. The three crew representing the team recieved rapturous applause at the end of the statement. No info given on pausible causes as an investigation is under way.

[PPRuNe Pop]

Appearing on TV Capt Birkill with his SFO, John Coward and Sharon Eaton, Purser with Willie Walsh in attendance made a short statement which was limited in content as one would imagine at this stage and with the AAIB still deliberating.

The most notable comment from Captain Birkhill was that SFO John Coward was PF and it was he that carried out the landing.

The Captain also made it known that his team on board was 'outstanding' and that Sharon attended the FD to ensure that they were OK before she herself descended the escape chute.

[RatherBeFlying]

Bystander reports of abnormally loud engines, perhaps augmented by RAT, may be ascribable to the fact that the a/c was abnormally low.

If it went overhead at, say, 50' instead of, say, 200' at a bystander's viewpoint directly underneath, the perceived noise level would be 16 times higher according to the inverse square law.

[Organic]

Is it true that B777 have a history of false negative engine fire warnings?

Would the AFDAS system have sent something out by ACARS before any engine failiure? Perhaps a message was sent out by ACARS over VHF and captured by some hobbyist.

Just a guess

[sandbank]

Hi Hetfield. Apologies for lack of clarity! "We" = our company Merlin Broadcast which makes tv factual documentaries. We negotated for months with BAA to try to get permission to locate live cameras at Heathrow to provide rolling live coverage for a dedicated cable/internet channel- but in the end they said "no" (and this was before 9/11).

Anyway - now at least someone HAS come up with video of the incident - albeit on a mobile phone. It shows the aircraft coming in very low and with an unusual nose-high attitude.

Also , of course, the crew have since been on tv and it appears the Senior Flight Officer - not the captain - was in the left hand seat and handled the landing.

[luvly jubbly]

The Senior FIRST Officer would have been flying from the RIGHT hand seat!:ugh:


Guess the Sun headline tomorrow........."Hero Coward?":rolleyes:

Can someone please stop the BBC from calling it a Boeing Seven Seven Seven??? It's a "Triple Seven" if you're reading this from The Beeb!:=

[Organic]

Is it true that B777 have a history of false negative engine fire warnings?

Would the AFDAS system have sent something out by ACARS before any engine failiure? Perhaps a message was sent out by ACARS over VHF and captured by some hobbyist :confused: or by one of those ACARS websites.

[regularpassenger]

Hi,

SLF here so please treat me with the contempt I deserve. I won't pretend to know anything but I do have a question:

Regarding the increase in engine noise heard by witnesses on ground, is it possible that given the close seperation of aircraft in the Heathrow approach (is it 1 min?), that the increased noise could have been aircraft behind in the "queue" going around?

RP

[NigelOnDraft]

was in the left hand seat and handled the landingErrr sandbank... where on earth did you get that from :ugh:

[HeliCraig]

I would like to know what plans with AAIB / BA have to shift it?? Anybody heard any rumours?

Surely they won't try and move it to Farnborough? Perhaps somewhere can be found at LHR for it, and then can put a temp hangar around it? (similar to Avro at LCY), or maybe even find space in a normal hangar?

Of course, I guess it all hinges on whether it is confirmed as a hull loss or not (I would have thought so, but I have only seen it on TV) - if so then they might as well cut it up and take it to Fb!

HC.

[dns]

There's the space over near the hangers were the old Trident used to sit... Would have thought it would probably end up there for a while.

[Jaxon]

"We" = our company Merlin Broadcast which makes tv factual documentaries.

Also , of course, the crew have since been on tv and it appears the Senior Flight Officer - not the captain - was in the left hand seat and handled the landing.

I hope you keep working toward that goal of "factual".
You aren't quite there yet.

[Clarence Oveur]

Being a hydro-mechanical fuel control operator, I am curious as to how the FADEC and throttle signal are powered.

Do the FADEC have it's own power supply or is using aircraft power, or both depending what's available? What powers the throttle position signal? Same supply as the FADEC or is it split?

[ryani210693]

Hi there.

After reading the Mirror today about the incident, i don;t know if anyone else has seen this about "automatic reversing thrusters" and also noone can seem to get the correct story right now about the Primer Minister either about whether he was on the motorway about to be struck by the aircraft, or waiting to depart on his plane.

Anywhos, about the plane. The Mirror had a section about a theory of automatic reversing thrusters that usually come on a few feet before landing. After reading this and it saying that they might have came on too high up as part of a malfunction by themselves, i couldnt help but think what a load of rubbish they are talking!

Am i wrong about automatic reverse thrusts feet from landing or am i right that this is not actually in aircraft and the thrusters do not go on until the manual pull back on the thrusters throttle/lever. It really annoys me when papers have no clue what they're talking about. I have seen many other silly mess ups, but this stood out too much and are they not talking a load of rubbish?

Ryan.

[doubtfire]

Aaaaaagggghhhhhh. Please please please could the media try and engage brain before blurting out total garbage and supposition. I can see how they must be totally confused with the fact there was more than one pilot on board. What a revelation. Who would of thought that. Next comes the incredibly amazing revelation that it was the Captain`s Co-Pilot that was handling the aircraft. That would be the Co-Pilot belonging to the Captain would it!!!!!!!!!! He`s called a First Officer and he doesn`t belong to anybody you gits.
More`s the point, not that the media would understand such things but if the left seat has just got his command on 777 having been FO on 747s for the last 15 years (Lets say, just 100 hours on type and in the left seat) and the F.O. has been sat in the right seat of 777 for the last 10 years....... Who would you suppose might be in the better position to handle in this sort of instance. Aaaaaaggghhh, Now the beeb are banging on about "his Co-Pilot") Am getting very angry now.

[pasoundman]

" Who are these "experts" that keep getting drafted in? I worry that I may be missing out on a profitable niche as a self-appointed expert in something. "

Last I heard, most news organisations don't like paying.

That may help explain the quality of 'expert'.

[doubtfire]

Now we`ve got some ex BA Captain baging on about how "co-pilots" are actually allowed to take control when the weathers nice.
Now I`m really getting very angry.

[IcePack]

So a total elec/loss of thrust. FOR UNKNOWN ?? reasons and the AAIB have not recomended that the world wide 777 fleet be grounded till they know the cause. Methinks they know the cause & all this speculation is a load of tosh:confused:

[SOPS]

Doubtfire...you are kidding right?? !!! ??.....No I thought not..where do they find these jerkks:ugh:

[hetfield]

@IcePack

Spot on!

I fully agree. This makes sense.:)

[decktwo]

Does anyone really think that if a 777 had total power loss, and no reason could be given straight away that they would let the rest of the 777 fleet keep flying??? I think not......

Looking forward to tomorrows AAIIB report......

[Tight Slot]

Just an A330 jock here, would the ADI and the HSI (or the PFD and ND in "bus" talk) on the right hand side still have power after (pure speculation) both engines fail? The 330 would be down to emerg bat power thus only the left screens would be showing any info...

[aviate1138]

AAIB Part report.

"Examination of the aircraft systems and engines is ongoing.

Initial indications from the interviews and Flight Recorder analyses show the flight and approach to have progressed normally until the aircraft was established on late finals for Runway 27L. At approximately 600 ft and 2 miles from touch down, the Autothrottle demanded an increase in thrust from the two engines but the engines did not respond. Following further demands for increased thrust from the Autothrottle, and subsequently the flight crew moving the throttle levers, the engines similarly failed to respond. The aircraft speed reduced and the aircraft descended onto the grass short of the paved runway surface.

The investigation is now focussed on more detailed analysis of the Flight Recorder information, collecting further recorded information from various system modules and examining the range of aircraft systems that could influence engine operation."

[SLF3]

In the Flight Gallery of the Science Museum in London there is a slice through the fuselage of a Boeing 747 - basically a one seat-row cross section from the double deck level behind the flight deck. It is in BA livery.

Suitable home for part of the 777?

[Just This Once...]

Eeeek!

:uhoh:

[sandbank]

Heard it on - I think - on Sky News.

From the captain's statement it wasn't clear what part he played in the emergency himself

He said "Flying is about teamwork - and we had outstanding team on board yesterday. As captain I am proud to say every member of my team played their part expertly yesterday, displahying with the highest standards of skill and professionalism - no one more so than my senior first officer Officer John Coward who was the handling pilot on the final approach and did the most remarkable job. My first officer Conner McGuinness also continually assisted. "

The BBC reported that the Captain had taken the outward leg of the trip and would not necessarily have flown the return leg.

So - you tell me - who was sitting where?

[doubtfire]

BBC now reporting that "Accident Investigators" are stating that engines failed to respond during landing that they didn`t respond to demand for increased thrust at 2 mile point.
Any 777 drivers care to comment on a standard approach as to when engines should spool up from idle after selecting landing flap and a/c airspeed back at vref. Could it be at the 2 mile point (ie 600ft) or maybe nearer 3 miles? Plenty of time maybe for a mayday call but no disrespect to the crew, other things on mind and hands busy etc etc.

[APG]

From the AAIB initial report:

>>>Following an uneventful flight from Beijing, China, the aircraft was established on an ILS approach to Runway 27L at London Heathrow. Initially the approach progressed normally, with the Autopilot and Autothrottle engaged, until the aircraft was at a height of approximately 600 ft and 2 miles from touch down. The aircraft then descended rapidly and struck the ground, some 1,000 ft short of the paved runway surface, just inside the airfield boundary fence. The aircraft stopped on the very beginning of the paved surface of Runway 27L. During the short ground roll the right main landing gear separated from the wing and the left main landing gear was pushed up through the wing root. A significant amount of fuel leaked from the aircraft but there was no fire. An emergency evacuation via the slides was supervised by the cabin crew and all occupants left the aircraft, some receiving minor injuries.

Initial indications from the interviews and Flight Recorder analyses show the flight and approach to have progressed normally until the aircraft was established on late finals for Runway 27L. At approximately 600 ft and 2 miles from touch down, the Autothrottle demanded an increase in thrust from the two engines but the engines did not respond. Following further demands for increased thrust from the Autothrottle, and subsequently the flight crew moving the throttle levers, the engines similarly failed to respond. The aircraft speed reduced and the aircraft descended onto the grass short of the paved runway surface.<<<

[PJ2]

TS;

Only according to the B777 AOM, (I'm 340/330 qualified, not B777), the Captain's flight instruments are available on standby power if there is battery only available; if the RAT generator is available, the F/O's flight instruments are also available.

This has been quite a beginning to 2008. Three major incidents, no fatalities thank goodness, and superb, professional performances from aircrews all around, notwithistanding original causes which even today are not known or at least made public.

Random or a pattern? Aviation, especially the large transport sector, is so safe now that establishing patterns with so few data-points is difficult yet in the end this question is going to be asked and when deeply examined enough, "random" causes give way to reasons.

It's already going to be an interesting year for safety people. Let us hope that it gets no more interesting.

[NigelOnDraft]

So - you tell me - who was sitting where?Except for Command Training, and Relief Crew at altitude, the Captain will be LHS, (S)FO RHS. Controls are identically duplicated, as easily (and as often) is flown from the RHS...

From the captain's statement it wasn't clear what part he played in the emergemcy itselfIn most "Emergency" situations, the NHP will be busier than the HP ;) So the fact that the SFO was flying, meant the Captain was probably working hard at drills / assisting / diagnosing....

[randomair]

sandbank,

The first officer, who was not at the controls would of been sat on the jumpseat.

randomair

[luvly jubbly]

standard stuff Sandbanks!
Captain in Left hand seat. SFO flying aircraft from Right hand seat, FO (surplus to requirements, though could assist with checklists etc) sitting behind on jump seat.

[Random75]

Here's the AAIB link... http://www.aaib.dft.gov.uk/latest_news/accident__heathrow_17_january_2008___initial_report.cfm

[md80forum]

Quick guess before I start sifting through this thread: British operator, crew and maintenance, so it must be Boeing's fault.

:}

[Val d'Isere]

Question 1 - If both engines fail to respond to thrust levers then is fuel starvation to both engines a possibility?

Question 2 - Do BA 777 procedures insist that each engine is fed from separate fuel tanks for approach and landing, or would it be permitted to feed both engines from one tank?

Question 3 - What warnings and indications would the 777 automatically give if the fuel content in a fuel tank was approaching zero?

[PJ2]

Does anyone really think that if a 777 had total power loss, and no reason could be given straight away that they would let the rest of the 777 fleet keep flying??? I think not......

Even with the AAIB initial report, these are not instantaneous, clear-cut decisions. There is some investigation to accomplish before it can be determined where the seeds are - in this aircraft, or fleet-wide. Also, as unseemly has it may be to contemplate, the realities are such that commercial pressure is a factor. Such factors will be a part of a very large picture even now.

[toro]

md80forum,

what have you been reading or are you a wee bit sensitive NOBODY has even mentioned blaming Boeing who have been proven again that they make a bloody strong aircraft.

[Time Traveller]

That was my first thought Val - If the fires go out for whatever reason, then they aren't going to respond to auto-throttle or manual commands...

but then again, I'm sure the AAIB would have mentioned the obvious loss of EGT on the trace if it was a flame-out, rather than this 'failure to respond to commands" - so it would appear they went into snooze mode at idle?

Yikes indeed, and mucho kudos to the crew.

[wideman]

Wondering about how much time they had?

If in fact the situation became known at 2.0 statute miles out and they averaged a ground speed of 150mph, they'd have had 48 seconds before making contact with Earth. So with the different variables (who knows what the real average speed was), it's likely that they had somewhere between 35 and 75 seconds.

Not exactly a whole lot of time to develop and execute a careful plan.

[FIRESYSOK]

BA is apparently confident their crew have saved the day. I for one, would not stand in front of a huge audience of media and colleagues if I thought for one minute I may have overlooked or mishandled the situation. So, if there is a generic flaw with the aircraft I think something would have come out by now. I suspect fuel quality may be of importance here.

[G-CPTN]

Does this look like an engine that was rotating at speed when it hit the dirt?
http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm3.jpg

[fox niner]

Question 1 - If both engines fail to respond to thrust levers then is fuel starvation to both engines a possibility?

Question 2 - Do BA 777 procedures insist that each engine is fed from separate fuel tanks for approach and landing, or would it be permitted to feed both engines from one tank?

Question 3 - What warnings and indications would the 777 automatically give if the fuel content in a fuel tank was approaching zero?
Today 19:17

1. I guess fuel starvation could be one of the possibilities.

2. according to boeing procedures, it is allowed to feed both engines from 1 tank during landing. crossfeed valves may be opened during landing. I don't know about BA procedures though.

3. when any wing tank reaches 2000 kgs or less a FUEL QTY LOW advisory emerges on EICAS. it has a checklist procedure. it calls for flaps 20 approach, all fuel pumps on and both crossfeeds open.


Now then. What is this accident going to do with the ETOPS status of the 777? Does this count as two IFSD (in flight shutdowns) in one day?

[KarlADrage]

From the preliminary report:

A significant amount of fuel leaked from the aircraft but there was no fire.

[TURIN]

md80forum
Quick guess before I start sifting through this thread: British operator, crew and maintenance, so it must be Boeing's fault.


Some of the maintenance is done in south Wales so it was probably a miner fault! :}:E:O:ok:


Hat, coat.....:ouch:

[ZeBedie]

Anyone remember the “uncommanded rollbacks” the 535-E4 used to suffer? When power was required to stop a descent, the engine would remain in a sort of sub-idle. RR would investigate and declare the engine fault free.

[sixela]

Apparently not - http://news.bbc.co.uk/1/hi/uk/7196128.stm
(apologies if already posted - big trouble with little server)

[Flintstone]

Only in Britain would pilots get a standing ovation for crashing a plane

You still offering to fly for free 3bars? They do say you get what you deserve.

[manrow]

A ridiculous post 3BARS.

Despite what the press keep calling this event, it was wonderfully enacted by the flight crew to PREVENT a crash!

They all deserve our support.

[Squealing Pig]

Now that the AAIB have stated the Trents failed to respond. Are the power levers on a 777 PHYSICLY connected to the engines as in a conventional non fly-by-wire aircraft or is it inline with Airbus and just sends a signal to a computer that then decides if you really did want a power change or not ?

[Pancake]

ZeBedie wrote:

<<<Anyone remember the “uncommanded rollbacks” the 535-E4 used to suffer? When power was required to stop a descent, the engine would remain in a sort of sub-idle. RR would investigate and declare the engine fault free. >>>

Mmmm. IIRC the fuel controls on the Trent 895-17 are made by the same company that made those on the 535-E4. I wonder ...

P. :(

[kwachon]

So much information, so many possible causes, so much speculation. Come on guys, lets get it together, a captain and his crew make decisions together, it's called CRM, lets not allocate blame or otherwise to anyone until the facts are revealed. A good outcome to a bad situation, well done to all involved. Irrespective to the cause or outcome you did well and that should to be recognised.

[Earl]

On one of the engines the N-1 blades are broken off and appears to have been working.
Perhaps it started spooling up just prior to impact.
Both engines failing at the same time is a bit tough to believe provided there was fuel on board and being fed to the engines.
Something very strange here.

[armchairpilot94116]

http://news.yahoo.com/s/afp/20080118/wl_afp/britainchinaaviationaccident;_ylt=AkgBDkzMhEvM6vYeZpJ3TGFbbB AF

copilot hailed

http://news.yahoo.com/s/ap/20080118/ap_on_re_eu/britain_plane

engines failed


Great that all are ok.

[26point2]

Hi
just a thought..

Each engine will be totally independant of the other, each has its own fuel suppy, fuel pumps, hydraulics, Engine computers (FADECs) etc.

a while ago i went to pick up an aircraft (executive jet) from servicing. it had just had two new fuel guages fitted but niether of them would work even though they each had their own electrical source and were reading from diferent tanks.. the engineers were scratching their heads! as the guages worked when bench tested.

we all know how engineers dont like us pilots to tell them why something isnt working but i sugested the only common factor these guages had was "earth"
they dissmissed my thoughts and sent me back to the hotel.

The next day a diferent engineer told me that it turned out the guages had not been properly earthed when initially fitted but all working now so off we went.

my point here is once again the only common factor these engines have is all their electrical components are earthed...

[Private jet]

Not read the pages & pages of text here but..... i think a good place to look would be the fuel filters to each engine....are they full of water? The fuel would have been cold after a long sector and i don't know the fuel heat system on a 777 but i guess its the auto cycle type. If this failed the filters would gradually clog up with ice and restrict fuel flow. Just a thought.

[llondel]

my point here is once again the only common factor these engines have is all their electrical components are earthed...

They certainly are now! Bit of grass and a few rocks as well, I'd expect. :}

Ummm... Taxi to Jet Blast!

[apron]

not read all the posts but has fuel starvation due to water in the tanks been looked at??

[grafity]

Private jet, if the fuel filters become blocked they get by-passed.

26point2, I presume what your suggesting is maybe a possible surge of some sort, surely though all systems would be adequately surge protected, anyway, the reports from passengers is that everything in the cabin was working fine all the way down and the whole airframe should be electrically neutral. If your suggesting maintenance error of some sort then it's very unusual to say the least that two or more system would fail at the same time.

[ZeBedie]

Two engines being fed by one tank? It's possible on most aircraft and could certainly cause an accident like this. If this was the cause, I'm pretty sure the capt would not be on TV receiving applause.

Also, if fuel contamination/starvation was the cause, I reckon the flame-outs would have been separated by a significant interval, due to each engine having a separate fuel system, in effect.

[Check Airman]

AAIB preliminary report is out.


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

"Initial indications from the interviews and Flight Recorder analyses show the flight and approach to have progressed normally until the aircraft was established on late finals for Runway 27L. At approximately 600 ft and 2 miles from touch down, the Autothrottle demanded an increase in thrust from the two engines but the engines did not respond. Following further demands for increased thrust from the Autothrottle, and subsequently the flight crew moving the throttle levers, the engines similarly failed to respond. The aircraft speed reduced and the aircraft descended onto the grass short of the paved runway surface."

[On GS]

qoute:
Did anybody notice that the rudder on the wreckage is fully deployed to the right?
FLY SAFELY
DOVES


Well, with the fairly strong SW wind and, I would think, the hydraulic pressure zero, . . . . . . .:hmm:

[lomapaseo]

With the benefit of the initial factual report

Both engines failed to repond at the same time in a critical flight regime from a presumably low power (flight idle?)

Additional unverified reports suggest that a loud engine running noise was heard before impact

Some have commented on the different conditions of the two fans (one with many broken blades, filled with dirt and one with much less damage and the dirt only seen in front of the fan)

Possibilities include a common cause associated with both engines (either at the engine level or the aircraft system level) and that one engine may have belatedly responded.

If the part in the bolded is correct than that area deserves the most attention in the next briefing

[NigelOnDraft]

Alex What are the chances of the RR Trent fleet being grounded? (G-YMMA to G-YMMO)RR put out, I believe, a statement to clarify the engines had not (necessarily) "failed", just "failed to respond".

The system will be complex, no doubt more so than even the Flt Crew manuals will say. The TLs will be manufactured by Boeing, and the fuel injectors by RR. Between these 2 points will be numerous mechanical components, electrical boxes and wires, and fuel componenets. Some will be Boeing sourced, and common to all 777s, and some will be RR sourced.

The AAIB said as much The investigation is now focussed on more detailed analysis of the Flight Recorder information, collecting further recorded information from various system modules and examining the range of aircraft systems that could influence engine operation.and without further info, one does not know if this is a RR 777 problem, a 777 problem or even lots of types :ugh:

[NigelOnDraft]

Possibilities include a common cause associated with both engines (either at the engine level or the aircraft system level) and that one engine may have belatedly responded.Whilst #1 has suffered more LP damage, and thus seemingly at higher power, it also suffered a lot more damage full stop i.e. the fan case, which will disrupt the fan, maybe was disturbed a lot more/earlier. #2 seems fairly intact, and just has hoovered up a lot earth :eek: #2's fan case, IMHO, may not have even been disturbed :ooh:

[EGLF24]

The AAIB's initial report states that both engines failed to respond to commands for increased thrust. It doesn't say "the engines failed" or "the engines stopped". In other words the implication is that the engines were still running but were stuck at the settings applied prior to the 'fault(s)' occurring. All the continued talk on hear about blocked fuel filters/ice in the fuel and indeed, no fuel, would surely only be relevant if the engines had completely stopped - something the AAIB report does not state.

Also on the subject of fuel, I have seen/heard it stated several times (including on here) that at that stage of the flight all remaining fuel would have been in the wings and therefore with the fuel in each wing feeding its respective engine. If this is indeed the case, surely the subject of fuel cross feeding is not relevant?

[Albert Driver]

What are the chances of the RR Trent fleet being grounded? (G-YMMA to G-YMMO)

I think this happened before on the first B757s, without such a dramatic outcome. IIRC for a while there was a minimum N1 that had to be maintained on the approach to prevent the engines going into a sub-idle condition in the event of a particular failure (I can't remember what. I'm still trying to find the appropriate technical newsletter in my archive).

This permitted the aircraft not to be grounded while checks were made and the requirement was then lifted. This sounds quite similar.

The photos of the wreckage show the right engine blades intact suggesting it subsequently completely ran down before impact, while the left engine blades are torn off but with little damage to the casing suggesting it was still running at impact but couldn't be accelerated out of sub-idle.

As regards the co-pilot continuing to fly the aeroplane, I think this was a good decision by the captain, enabling the more experienced pilot to try and find the root cause of the problem. Unfortunately there was just insufficient time remaining at such a low altitude.

[Luc Lion]

Wonder whether the 787 airframe will be able to take that sort of abuse, and stay intact. Any materials engineers care to comment?

HeliCraig, answering briefly your question :
there has been a debate last fall about the 787 structural resistance in case of a crash landing.
The question has been triggered by a letter addressed to the FAA by a Boeing engineer with a long structural design experience.
The FAA rejected the engineer's criticisms in october.
The letter of the engineer: http://seattletimes.nwsource.com/ABPub/2007/09/17/2003889769.pdf
A paper on FAA's rejection (sorry couldn't find the FAA's formal response) : http://www.asminternational.org/MSTemplate.cfm?Section=News_Releases2&Site=SMST&template=/PressRelease/PressReleaseDisplay.cfm&PressReleaseID=1247&News=1

If you are interested in that subject, I suggest you pursue it in the thread devoted to it:
http://www.pprune.org/forums/showthread.php?t=292713

Luc

[Unwell_Raptor]

Like most people (even most Prune readers) I am not a pilot. I have nothing to add to what has been said about the accident but I must say how revealing it is when some people completely lose it because 'non-professionals' ask questions and, yes, speculate about the accident. More than 90% of people in any airliner are not pilots, but their a*ses are on the line just the same as the guys at the front.

The public want to know and are entitled to know what goes on. Deference is dead. If you are a pilot, the rest of us are customers. Allay our fears. Tell us what you know. Some questions will be stupid, some fears irrational, but the public are still entitled to courtesy and consideration when they ask for information or reassurance.

It's called professionalism actually. Doctors are used to dealing sensitively with the fears of their patients. try to emulate them.

[NigelOnDraft]

Has anyone else considered the possibility of there being no fuel left?Errr... so how did the engines stay running on no fuel :ugh:

[derekl]

PPRuNe is a great forum because it is, within limits, reasonably open to non-Professional Pilots. There are those like myself who have such a deep-seated love of flying that they will travel in back of a 101% loaded 747 and still smile at the experience.

But like others, I have a real connection with all this stuff. My software engineering company supplies software to Boeing: as soon as I see something like this, I really want to know more about what *may* have happened. It's almost certainly nothing to do with us, but we live and learn very quickly about doing things better. We are thirsty for knowledge, learning and correction, particularly where systems failure may have played a part.

We need our forum, and this really is an excellent one. Early speculation can be constructive, provided it is well-informed.

[bassanoclapper]

not read all the posts but has fuel starvation due to water in the tanks been looked at??

It has and the grapevine suggests that any of the fleet recently returning from PEK are having fuel samples taken

[Sunfish]

I'm a low time PPL with some airline engineering experience but some of the speculation here is mind bogglingly stupid. For the record, the autothrottle system will probably be made by Honeywell.

Ferchrisake fergetaboutit until the authorities provide a report or accept my interim explanation - it was ice on the points.

[bus me in]

Is there a Nigel out there that can clarify BA's monitored approach handover stage from PF to PNF? Well done to all the crew involved, esp the SFO who landed! We all know any landing you can walk away from is a good one.

[H.Finn]

Many, many years go, when I was a young pilot, there was an incident in where I live, with Airbus A300's. Company was Karair, at that time a charter subsidiary of Finnair, they had two A300's, with highest utilisation of the type then, basically flying non-stop between Finland and the Canary Islands. About 18 hours airborne per day per aircraft, if I recall correctly. At some point, it was discovered that there was a huge chunk of ice floating in the fuel tank of one of the aircraft, as the condenced water never had time to melt, and thus had never been drained from the system between the flights. The aircraft had actually been very close to fuel starvation because of this. Of course, about 20 years have passed, lessons have been learnt, and this could not happen again, couldn't it...?

[Green Guard]

#401 #419 too
apron :
not read all the posts but has fuel starvation due to water in the tanks been looked at??


Well if you fly inverted in this part of world (or if you fly not inverted in Oz), you may get a problem with a water in fuel tanks AT THE END OF FLIGHT !

[ILS27LEFT]

Excellent team, both in the flight deck and in the cabin.
Gliding down a 767, without both engines from 2 miles away, it is not as easy as it sounds. Obviously the weather helped, the wet grass and soft mud helped, the visibility helped, the type of aircraft helped, but it could have all gone terribly wrong. Just a tiny mistake could have meant disaster.
Same type of incident on 27-right could have had totally different results as well, with the same crew, but we cannot ignore the objective fact that the two men in uniform at the front did an incredible job, they performed the best possible landing for the given conditions. They deserve a huge medal.

We also have to thank the extremely professional BA Cabin Crew who have again demonstrated how essential good training and skills become in case of a real emergency.
This should put a bit more into prospective the attitude of those moody passengers who often enjoy to treat Cabin Crew with disrespect, especially those in the Premium Cabins.
Yesterday they were all saved, also by the Cabin Crew, and this was the team's aim whatever their behaviour had been on board during the previous 12 hours.:mad:

This is a lesson for all.

Somebody here has even criticised the pilots for not advising the Cabin Crew of the impending crash-landing, but we all know well that in those precious seconds the main priority was to bring the machine down in the best possible way. Any distraction would have proven fatal.

Well done to all BA crew, you have demonstrated again that "serious training" is essential when you have to effectively deal with emergencies. Cabin Crew is essential too.
But lets' remind to all involved that in all fields, in all industries, we should never become too slave of our own procedures, e.g. if the pilots would have wasted time on "formal procedures" (e.g. "announcements") therefore under-estimating the real danger, everybody would have possibly died.
:yuk:

Looking back they have done a perfect job.:E : a perfect landing of a 767 without both engines, on the grass.

Why both engines failed?..think: what is the only bit they have in common?...:ok:

[eagle21]

When they say there was no response from the engines does it mean the engines did not react to the demand?

[Jumpseat777]

I cant believe all the horse%$^ that is put on here...I mean seriously if you dont know what you are saying and no one knows everything then please go ahead and say it first...Now I am not going to speculate at all on the crash..but please some simple facts on the 777 as someone who works on it everyday..
1.B777 is a fly by wire aircraft..it is not as simple as a wire to an engine..please
SYS involved include AIMS CMCS Arinc 629 OPAS FADEC

Throttle inputs go to an AIMS(Airplane Info Mngmnt Sys..and vice versa
Engine is managed by a dual channel FADEC system. The EEC is part of this system(the heart).The EEC ctrls
Engine Systems
Starts and Autostarts
T/R operation
Power to the EEC is thru dedicated alternator via PCU(Power ctrl Unit)

The Trent 884 is growth version of the RB211 developing @84000lbs of thrust
Fuel supply to this engine from airplane fuel system thru eng fuel pump(two stage) Pump supplies fuel to Fuel Metering Unit and servo fuel for actuators.Fuel flow tx and thermocouples supplies fuel flow and temp readings to cockpit via EEC.

APU is a electric and pneumatic power source both on ground and in air.
Also has a FADEC.In Air mode APU started by loss of power to both electric buses
A cold start APU would require approx 45 sec to strt from start command to being online functionally.that is able to supple electrics and pneumatics. Dual starting sys electrics and pnuematics if air px available air starter used. APU can start upto cieling for this aircraft 43100 ft for this aircraft. It is routinely done a s a test procedure during flights. APU has a an APUC for ctrl.

Fuel SYS
One ctr and two main tanks later version has larger tanks not more .At low fuel in center tanks automatic fuel feed from main tanks, and center automatically feed wing tanks.The FQIS( fuel quantity indicating system) uses ultrasonic probes not capacitor type. Same also used to detect water!
Ans also sends maintenance alert if water detected. Low fuel quantity also shows as an alert this time on EICAS and tank readout if particularly low on one.All dark panel involes all buttons and valves in for flight unless isolating for trouble.

Electrical Power
NBPT(no break power tx principle)
ELMS (Electrical Load Mngmnt Sys) This ctrls distribution of power on aircraft
Hardware includes the obvious
1 IDG 120Kva each per engine
1 Genny on the APU also 120kva
2 BUGs(backup generators) 20kva each variable freq converted to constant by backup convertor
5 TRU (Transformer rectifier unit) make dc power
1 RAT supplying 7kva
Main and APU batteries
Power sys normally operates as two independent channels Each channel one bus each bus supplied by onside genny.Apu can supply either or both with load shed coming in on overload.
Ground handling bus supplied by APU
Hot battery bus supplied by ground service bus via main and APU battery chargers
Stdby bus rcvs power from left tx bus or from stdby inverter if loss of power
BUGS are always running unless INOP and will supply pwr if main ac bus looses pwr.
BUGs not available then RAT will supply power to Flight instrument buses
ELMS GCU and BPCU montor ctrl and distributed electric power.

Now thats just an overview...just to correct some of the $%$ written here, I am sorry but by mouthing off people here are no better than those overpaid idiots on TV who then mouth your words.

The informed people here who have held off judgement before final analysis is available bravo.... but one thing I was told through school would be that no one thing can bring down an aircraft its always a chain of events not immediately visible to general eye. Crash scene footage or the way certain items are after the fact can say or do nothing this isnt CSI lol!!!

If any facts above are untrue please do correct me.

Thanks

[asuweb]

It means simply that the engines did not respond to a demand for increased thrust. The reasons for this will be the focus of the investigation.

[Pancake]

Eagle21 When they say there was no response from the engines does it mean the engines did not react to the demand? From the AAIB today:

At approximately 600 ft and 2 miles from touch down, the Autothrottle demanded an increase in thrust from the two engines but the engines did not respond. Following further demands for increased thrust from the Autothrottle, and subsequently the flight crew moving the throttle levers, the engines similarly failed to respond.
So the answer is 'yes'.
P.

[Luc Lion]

...
At some point, it was discovered that there was a huge chunk of ice floating in the fuel tank of one of the aircraft, as the condenced water never had time to melt...
Ice floating on Jet A1, I'm having problem understanding this.
Ice has a density of 0.9167 kg/L at 0°C
Jet A1 has a density of 0.775–0.840 kg/L at 15°C (ref density being 0.81)
Their density will increase at lower temperatures with some differential, but not to the point of inverting their 10% difference...

[interpreter]

Jump Seat 777. Well you certainly gave it to us. Well done - and thanks for taking all the time to put that lot together. I must confess that as a mere ex-RAF and now PPL the shear/vortex theory met the description of violent banking and porpoising on late finals with high engine noise. Just goes to show how wrong one can be. Obviously the old adage "convert speed to height" whenever you can worked and full marks to the officer with hands on.

Looking forward to hearing the full story, especially what steps the flight deck took to remedy the problems as they arose arose. One question: was the lower than normal glide path due to reduced power or was more power demanded as final flap selected? Is final flap selected on the 777 earlier than 600 feet - especially in gusty conditions?

[PlatinumFlyer]

Possible A/T problem? The report says the A/T tried twice, then the crew pushed the throttles. What would have happened if they disconnected the A/T, THEN pushed the throttles. I realize time was short.

[BGQ]

PJ2 the B777 does not have an equivalent for the airbus min groundspeed function

[frangatang]

Now perhaps the cabin crew can stop yapping away to each other when coming into land and bloody well pay attention in the last moments of flight. Brickbats to my cabin crew who were in great celebration at this event when we arrived some time later and spent an hour waiting for stand,which gave the precious dears a box4 plus overtime. Certainly know where their priorities lie!

[jwcook]

First off - well done ...

Now can anyone tell me if both the power buses failed if that would effect the engines in this way?.

As I understand it and please correct me if I'm wrong, the 777 FCS reverts back to a secondary mode then fails over to a very basic mode then finally to a last cable and pulley system for a few selected control surfaces.

If this was the case then I agree with the guy who said the pilots\crew deserve medals as big a as fryingpans....

Cheers

[BGQ]

Lets just get one thing right please. Every pilot professional or not is taught to Aviate (fly the plane) Navigate and then communicate in that order. With any low level emergency it is extremely likely that the flight deck crew are not going to get as far as communicate that is why we have highly trained professionals in the cabin who are trained to act on their own initiative in this type of circumstance.

[Clandestino]

It already did. There was fuel in the tanks - untill they ruptured following hard landing, that is.

[fox niner]

To Flip flop flyer and others who think pprune sucks bigtime: take it easy. If you really want to know what happened, log on to this site. Just take a look at the Gol-embraer accident in brazil and the ensuing thread. or take a look at the Congonhas 737 overrun thread. There are a lot of real professionals on this planet, and somehow they all meet here. That is a great resource! It is free, accessible to everyone and 24/7.
Sure, there will be sub-standard remarks by some.
But also remarks by people who actually know a lot of stuff. And they will keep the quality of the discussion in check.

When they say there was no response from the engines does it mean the engines did not react to the demand?

That is correct. The engines did not react at all (apparently). It is like flooring the pedal in your car and nothing happens.
---------------------------
Now, I have been thinking...... What strikes me as possibly relevant is that both engines failed to respond to A/T input simultaneously. What makes these two engines, fitted on this 777, not unique?

1. they are/have been in the same, identical ambient conditions from PEK to LHR. ---- cold soak problem of some sort?
2. they are consuming the same fuel.---- bad quality uplifted in china?

I would discount fuel starvation. It says in the AAIB preliminary report that a lot of fuel was leaking from the plane. So evidently there was some on board. Also, suppose the crew left the crossfeed open and forgot to close it, when balancing fuel. And thereby depleting one wing tank. This I find very unlikely. Because if that is what happened, one engine would quit before the other one does. This is because the engine, which is further from the wing tank that is being used, gets to consume the fuel that is in the crossfeed. It will give you about a minute's worth of additional fuel.
So in my more or less educated opinion, no fuel starvation. Not from one wing tank, and also not from both wing tanks. (i.e. 0000 kgs on board)

Bad fuel quality is always a possibility.
Also, some computer glitch. I have no clue at all.

Once again, two engines don't fail at exactly the same time. To me that sounds relevant.
Anyone else?

[Bill.Martin]

Now can anyone tell me if both the power buses failed if that would effect the engines in this way?.


I can't claim any B777 specific knowledge, but interesting question nonetheless as we are talking about an aircraft with FADEC.

So, at the risk of starting a Red Herring swimming, it's worth noting that there have been at least 12 reported incidents of power supply disruption on type, 3 of them classed as Major by Investigators, as detailed in AAIB SB/2007/2 (http://www.aaib.gov.uk/cms_resources/S2-2007%20N786UA.pdf) ...

[AirScrew]

I want to join those ahead of me on this thread and say that I am very dismayed at the content of this thread.

PPrune founders and moderators. You have a great forum.

To the Professional Pilots on this thread, and the amateur pilots behaving professionally: Congratulations on trying to keep a level head when all around you are losing theirs.

To the myriad of other pilots, amateur, pro, whatever, I am disconcerted and disgusted at your lack of professionalism.

I cannot imagine another profession/industry where such uninformed nonsense is pedaled in public. As a rough estimate, more than 50% of respondents who look like professionals' and quote facts, are so inept and wide of the mark, that they show their professional and industry in a very poor light. This can do nothing more than give the press on this forum the impression that there sporadic and patchy training and no SOP's.

It also worries me greatly when I ask myself how many of the 'pilots' on this forum could have coped with such a circumstance. Whatever the cause, it has to be handled. The lack of clarity, thoughtful analysis, and consistency is astounding.

[CityofFlight]

SLF here....could someone please tell me if 600 ft 2 miles out is standard? Seems pretty low.

It's a shame some folks here get their blood pressure up over another person's comments. Yes, opinions are like a$$holes and everyone has one. No need to be blasting, just ignore and look away.

Am still applauding the crew :D:D and mourning the loss of the 777. What a pity. :{

C of F

[iainfs]

600 feet is standard for 3 degree glidepath at 2 miles.

[H Peacock]

SLF here....could someone please tell me if 600 ft 2 miles out is standard? Seems pretty low.



300ft/nm ie 1500ft at 5nm = 3deg GP, so spot on!

:)

[Mad (Flt) Scientist]

I cannot imagine another profession/industry where such uninformed nonsense is pedaled in public.
ANY industry in the public eye is subjected to amateur opinions. laws are passed and government decisions made on how the "man in the street" thinks about a topic, not the "experts". Ask any genetics researcher in the USA. Or any nuclear power engineer, ANYWHERE. or any doctor. Or policeman. Or soldier. need I continue?
As a rough estimate, more than 50% of respondents who look like professionals' and quote facts, are so inept and wide of the mark, that they show their professional and industry in a very poor light. This can do nothing more than give the press on this forum the impression that there sporadic and patchy training and no SOP's.
I doubt anyone is deducing anything about airline SOPs from an anonymous online bulletin board. But if they were, the absence of that board wouldn't make them any more enlightened. They'd just ask someone down the pub for their opinion instead.

I really don't know why people get so torqued up; the title says "Rumour Network" not "Professional Pilots Accident Investigation Board". Especially at such an early stage one expects rumours and confusion. And even if much of what is suggested is wrong in a given case, it may no be wrong in terms of a topic to think of. For example, fuel starvation may have nothing to do with this accident - but how many people thought a little bit more about their fuel load today, I wonder ....

[pavvyben]

Is it possible that there was a FADEC failure of some kind?

[Spui18]

the title says "Rumour Network" not "Professional Pilots Accident Investigation Board"
Well quoted Mr Scientist.
The delightful thing about PPRuNe is that you can talk quite freely about the aviation world around you, as you see it. This is not an educational site per-sée (sp?)
Rubbish should be pointed out by all, but for the rest it's a free for (within reason) all.
Keep it up folks (and Danny)

IFTB

[Jeff Claims]

pavvyben - I don't think FADEC failure is likely, as there appears to have been a possible common-mode failure affecting the ability of BOTH engines to respond to throttle demands, and the FADECs on the two engines are functionally, electrically and physically independent.

Of course, it may not be a common-mode failure - failures of both FADECs occurring with a short time of each other are not impossible, just very unlikely.

JC

[NigelOnDraft]

JS7771.B777 is a fly by wire aircraft..it is not as simple as a wire to an engine..please
SYS involved include AIMS CMCS Arinc 629 OPAS FADEC

Throttle inputs go to an AIMS(Airplane Info Mngmnt Sys..and vice versa
Engine is managed by a dual channel FADEC system. The EEC is part of this system(the heart).Thanks for that...

The "Safety Case" for any 2 (or more) engine aircraft is that it can afford a single engine failure for any of many causes. On takeoff, approach, cruise or whatever...

Your post implies, but I am sure is a "simplistic" view, that 1 system (AIMS) could, at a single "point", cause both engines to fail - despite 2 independant Thrust Levers (Throttles!). This would seem to me the "Safety Case" principle is in doubt :rolleyes:

I fly what is known as the ultimate electric jet - A320 types... But, AFAIK, we do not have the equivalent of the AIMS, and that the 2 TLs essentially go to the 2 engines separately (I am sure, as with most things Airbus, I do not understand it completely!) i.e. to get a double engine failure, we require a double fault somewhere, which in probability terms is unlikely...

Any light you can shed on this aspect i.e. a single system (AIMS?) as a single "point" through which 2 x TL and ATHR control the gines would, errr, be "enlightening" ;)

[Clandestino]

Kudos to AAIB, preliminary report got out very quickly. Everyone please do read it.


Whatever happened here, it seems that one-sixty till four saved the day. Good thing that established by 1000 is not the way to play at LHR.

[max motor]

NoD

There air two independent AIMS systems (cabinets)

Baz

[reventor]

Sorry I'm too dense to keep up. A few questions:

1) Did the pilots deliberately put the plane down on the grass?
In the case of issues with the landing gear (as hinted in some unverified accounts) and/or they anticipated a stall and hard fall, perhaps the notion of a softer surface than tarmac might have some appeal.
2) Would the outcome, in retrospect, likely have been as fortunate had they landed (with same force) on the runway?
With the fuel spilling out, perhaps it was just as well they avoided the tarmac and a potential rain of sparks all over the place.
3) Was the stall-like nose up movement at the very end as seen in the video intentional or an unwanted consequence of whatever failures the aircraft suffered?
4) If intentional, what was the purpose of it, assuming the angle of attack was higher than it should have been for a smooth landing, as appeared to be the case to my untrained eyes?
5) It is generally not entirely unreasonable to assume that the timing of the failure was crucial? A little shift in time and they either fall down in the residential area or make a reasonably normal landing.

There, I've proven that I have no clue how these flying cans work, my apologies for interrupting your discussion. My reasoning above comes from a lifetime of never flying a plan. Just trying to get a grasp on some basics and perhaps understand how fortunate the outcome really was.

[AirScrew]

Mad,

we'll have to agree to disagree.

Your comments are aimed at the comments from amateurs on this forum, and you are right.

I'm concerned at the number of professionals (just check the profiles) who make incorrect or unprofessional assertions.
This isnt just any old group of chaps(ess') down the pub, its the elite of the flying fora.

[Bill.Martin]

I don't think FADEC failure is likely, as there appears to have been a possible common-mode failure affecting the ability of BOTH engines to respond to throttle demands, and the FADECs on the two engines are functionally, electrically and physically independent.


Although the design goal would be for the all engines to be functionally, electrically and physically independent, the QF2/7JAN08 incident (VH-OJM / MSN 25245) is being unofficially attributed to a common mode failure affecting the power feeds from all 4 engines and the APU (this was a 744).

And given the history of power supply disruption on B777 (see my previous post, referencing AAIB/SB/2007/2), I'd say that FADEC issues can neither be ruled in nor ruled out at this juncture.

[NigelOnDraft]

MM There air two independent AIMS systems (cabinets)
Thanks for that... just to check, 1 system is for Eng #1, and one for #2 etc.... not 1 AIMS system for #1 and #2, with a backup AIMS to be engaged when? how?

Reventor Did the pilots deliberately put the plane down on the grass?
had they landed (with same force) on the runway?
Was the stall-like nose up movement assuming the angle of attack was higher than it should have been for a smooth landingThere, I've proven that I have no clue how these flying cans workYour last point leads to the earlier... Where the aircraft got to i.e. ran out of altitude, at what speed, and at what "angle of attack", and related "rate of descent" are all fundamentally "linked" by pure physics. Given it seems thrust was fixed, the pilots' level of control was really related to balancing the other factors for the best possible outcome i.e. not being independantly "controlled".

As a pilot, and given what the AAIB said, I would say the combination of Angle of Attack, where it got to, speed it got there with etc. was pretty damn near "optimal" for survivability.... = I think they did bl**dy well ;)

[tubby linton]

The early fbw airbus have a tape connector under the thrust levers.It looks like the tape that connected your Pentium 0 desktop to a very basic printer.
Perhaps the connector has been bridged or earthed to produce a corrupted or missing signal?

[BerksFlyer]

Just a passing thought...

Why is the reference to AoA being made when it is impossible to tell the AoA just by looking at the plane?

AoA is the angle between the wind and the chord line. Not the angle between the chord line and the ground, which is infact pitch angle.

[EpsilonVaz]

The early fbw airbus have a tape connector under the thrust levers.It looks like the tape that connected your Pentium 0 desktop to a very basic printer.
Perhaps the connector has been bridged or earthed to produce a corrupted or missing signal?


Or perhaps a magical fairy was a stow away from China and used material from the throttle system to roll joints during the flight.

[Jeff Claims]

Bill.Martin - it is possible that there could have been a common-mode failure of the aircraft power supplies to the FADECs, but the FADEC's PRIMARY power sources are independent, dedicated, engine-mounted generators. A FADEC will only use aircraft power if its engine-mounted generator is incapable of supplying sufficient power, so common-mode loss of aircraft-supplied power would cause both engines to shut down only if both dedicated generators had also failed.

JC

[tubby linton]

Epilson.You obviously have never seen where coffee and other objects get to in a flightdeck!

[MikeAlphaTangoTango]

One thing I don't get. At 600', to be stabilised on approach, the engines should have been above idle thrust. So the statement from the AAIB they failed to respond to an increase in demanded thrust is only half the story. If they continued to provide the level of thrust they were already at before the commanded increase, there's no way they should have landed 1000' short of the start of the runway. Moreover, it appears that No2 was barely rotating when it swallowed a bellyful of LHR's finest turf. I wonder how far out the problems really started, 2nm or quite a bit further?

[Aileron Drag]

Taking a different angle on this, I was pleased to see that the FO has now been given credit. The public seem to think that an aircraft is operated by a 'man and a boy', rather than a team. I hope Joe Public (AND the press) take this lesson. It's teamwork.

Flying to the 'angels wings' on the 777 (the maximum pitch attitude) is very difficult, and one relies on one's colleague to advise on RoD, altitude, and lateral position in relation to the runway. This was a great team job. Having flown with Pete, it doesn't surprise me that he and his colleague did so well.

[ILS27LEFT]

OK, we know the 2 engines failed to respond simultaneously.
This is very strange, they are totally independent: only a couple of bits are shared, either fuel or throttle.
It has happened ok, we all know, but why it happened just on short final and not during the previous 12 hours of perfect functioning. The fact that this fault developed just a few seconds before touch down could mean this is more likely fuel related. Otherwise it must be something else, but what?
...fuel related?
If it was fuel related this was totally unexpected and all indicators were showing perfect values so it is possibly going to be some sort of sensors fault or fuel contamination, but if it is contamination why this became a problem only in the last 30-60 secs of a 12hr + flight?...

Excellent job done by all crew.
If you read this message please note I think you are heros.

[Danny]

Just a quick note to the detractors... you should see some of the stuff we have been deleting from this thread. If you think some of the speculation from some of the contributors is bad, you should read what we have had to go through and delete.

PPRuNe is not a definitive site and whilst the moderators are actively trying to keep some semblance of coherence and prevent the hoards of "experts" who post some astoundingly stupid theories, what remains is, hopefully, a reasonable selection of questions and suppositions that make the thread entertaining AND informative. I would really like to write a book with the content of what we have in fact deleted from threads like this. It would be a best seller in the comedy section of most bookstores. :rolleyes:

We try to keep the posts tracking along the lines of the subject matter. There will always be some deviation. Questions that are just so banal (in our humble opinion) or blatantly conjured up by someone with the IQ of a dipstick, together with responses equally as uneducated, are removed in order to keep things sane.

If you think the detractors are having a coronary over what they've read so far, they'd have been eviscerated if they'd have had to read the stuff we've deleted. There is a balance to be had and some very basic questions are allowed as they help to enlighten those who are not so sure of all the terminology to understand better what is being debated.

So, thanks to everyone who has contributed and "yah boo" to those who'se whose literary attempts have been removed for the sake of sanity and preservation of IQ and normal blood pressure. No need to respond to this post as it will also probably be deleted if it isn't relevant to the thread topic.

Please leave the rest of this debate to the issues and not the emotions of the Mr Angry's of Bournemouth. :hmm:

[Mechta]

Thanks to Noddyscar for this much earlier in response to my question:
"......Noddyscar Fuel Drain check on DY chk

On the 777 daily check for ERs you usually do the Fuel Drain check for water contamination

Drain 1 gallon from center fuel tank sump drain valve as per AMM.

I guess if this was not done in PEK due cold weather, the water content in the tank could have been higher than realised. Would explain both engines flaming out. Crew thinking indication they had fuel........"

Fox Niner wrote: '......The 777 is not prone to fuel icing. the fuel tanks are positioned in the wings in such a way that the OAT can not "reach" the fuel and cool it down as much.

I have not seen a colder fuel temperature than around -30 degrees C on the B777, also overflying siberia. A 747 is much more affected by fuel cooling.
In China we get uplifted with jet A1 or TC1. (russian grade).......'

I can't see how the wing design is going to make much difference to the fuel temperature, except that a thinner wing of larger area may cool the fuel more quickly than a deeper wing. The fuel is sitting on a slap of light alloy (the lower skin) with the ullage (air space) above it. The tanks are vented to atmosphere, so the fuel temperature is going to fairly rapidly cool to outside air temperature, but be warmed a bit by heat loss from the pumps and any pumped, but unused, fuel.

If the water in the fuel above the tank drain was frozen (is that possible?), might this have resulted in a false sample reading, if one was taken at PEK?

Are the jet pumps, to emulsify water in the fuel, in the engine feed tanks(?) running all the time, pilot actuated, or automatic as required?

The question I'm leading to, is whether water content in the fuel could have reached a percentage that it reduced the engine's performance enough to cause what happened?

The 777 uses a different (ultrasonic) fuel gauging system to just about everything else in the air. Could it have lead the pilot to believe he was looking at fuel when it was in fact water; if the water detector was fully submerged in water and not showing a water level? The fuel densitometer should have picked this up, but if it wasn't in the water, perhaps it couldn't indicate this?

Maybe the descent through moisture laden air, causing a lot of water to enter the tank vents, as the outside air entered to maintain pressure equilibrium in the ullage, was 'the straw that broke the camel's back' and the fires went out.

Jumpseat777 was the first to mention that the gauging system is ultrasonic. To clarify his description of the gauging system, the water detector is also an ultrasonic probe, but it points down, to detect a water/fuel interface, whereas the other probes (around 60 of them, all told) look up, to detect the fuel/air interface by measuring the speed of sound in fuel. This gives a fuel height, which if known in three places in a tank, gives a level, and hence a volume. The densitometer reading allows this to be converted into a fuel mass. It is conceivable that the software now allows the fuel probes to detect the false surface of water in them as a secondary return, but I am not aware of this. Can anyone confirm?

Elsewhere on the net, someone has stated that it takes seven gallons of water before the water detector gives a reading. Anyone know how many gallons of water it takes to fully submerge it?

[sevenstrokeroll]

wondering what the spool up characteristics are on the trent engine.

does anyone know if the plane had an uninterrupted idle descent from cruise?

just wondering...you guys know what I mean.

[Bill.Martin]

a common-mode loss of aircraft-supplied power would cause both engines to shut down only if both dedicated generators had also failed


JC: I agree, but given the AAIB statement that "engines did not respond", I would suggest we have no valid status information on the engines or their ancillary equipment (e.g. generators), so a common mode failure which could have affected FADEC can neither be ruled in nor ruled out from the current available information.

[Doors to Automatic]

Danny - Have you kept everything that was deleted? It would be great to see a comedy "out-takes" thread of the incident in JB :p

[non iron]

Difficult to believe the the problem developed at not much above flight idle at 400ft., a mile out.
Somebody is for the high jump.

[ILoadMyself]

AirScrew,

I am not worthy! Or deserving. Of your disapproval of the majority of correspondents on this fine site.

In the world outside the aviation industry anything that moves (or doesn't move) is open to scrutiny by would-be "barrack-room lawyers".

I've had a bellyfull over three decades.

The aviation industry is safe because it is supervised to a degree that most souls would find insufferable. None more so than the team on the flight deck.

Nature teaches us how to trust people. Hence, a decision was made to present the Captain, Senior First Officer and Cabin Service Director (apparently with orders not to look the least bit happy) to inspire public confidence.

The facts will out.

In Black Box Veritas.

Mr (Flight Lieutenant) Jonathan Tapper and Mr (Flight Lieutenant) Rick Cook did not have a Black Box. Soon, hopefully, their memories will receive the respect they deserve.

[Xeque]

Maybe all the cockpit screens went blue with the dreaded message 'Windows fatal error'.:ooh::mad:
Seriously, at that stage of a long flight, which tanks would be in use? Wing tanks, fuselage tanks or both? Would both engines draw fuel from the same tank at that late stage of the flight? What would make two engines, designed to operate independently, cease functioning together so late in the flight? Cross-feeding contaminated fuel? Well, maybe but surely that would have manifested itself as a problem earlier. I would bet that they didn't run out of fuel - there are reports in this forum of fuel leakage after the event and in an earlier post I mentioned the fire brigade hosing down under the aircraft long after the incident took place. I think the answer to this has to be (somehow) fuel management systems (computer) related so let's see.
Another (late) thought. Avgas floats on top of water (hence drain tests on my C152 for first flight of each day). What happens with Avtur? Is it lighter than water too?

[booke23]

A question for someone with 777 engineering/operations expertise.

Does the 777 have any sort of fuel heaters that heat fuel before the fuel gets to the fuel filters/water seperators?

If so, do these require to be switched off on the approach check list?

[pb365]

You obviously haven't been reading or listening to the news; the remaining fuel in the tanks was well above the permitted minimum.:=

[pb365]

According to the most recent news bulletin from the BBC a considerable amount of fuel leaked on to the runway - see my previous post.

[airmuster]

"Danny" & "Doors on Auto"

Have you kept everything that was deleted? It would be great to see a comedy "out-takes" thread of the incident in JB :p

Think it would be great idea.......... worth considering anyway.;)

[Green Guard]

Originally Posted by H.Finn
...
At some point, it was discovered that there was a huge chunk of ice floating in the fuel tank of one of the aircraft, as the condenced water never had time to melt...

I am sure it is possible to form and happen, but ONLY under one condition. If you are on domestic flight within Finn-land.....

[Jumpseat777]

For the record

Yes not part of the airplane its part of the engine...dual purpose cools the oil heats the fuel... Fuel/Oil heat exchanger..no switches no manual input works as long as fuel flows...

and someone asked about AIMs its dual its actually a cabinet full of IC cards called card files

[ILoadMyself]

Danny,

Outstanding work to keep the site going in the face of overwhelming demand.

I find your calm commentary and TightSlot's quiet, but uncompromisingly firm, good humour inspiring.

Even just seeing a contrail makes me happy. Flying should be impossible. Unless you're an angel.

God alone knows what cheers a hack on the rolling tv news. Other peoples' misery, I suspect. A life without romance is not a life IMHO!

[simfly]

The AAIB report implies (to me anyway) that the engines did not "cut out" as is being reported by many, but maybe stayed at the same power setting despite the movements of the power levers.... Obviously not being able to add power as required at that time resulted in a landing short.... if so, the opposite could also happen, the auto-throttle/crew trying to reduce power, and landing long if nothing happened :confused: Strange goings on onboard G-YMMM!

[sector8dear]

Exactly, stayed at "current" power and perhaps after full landing flap applied. Think is "total" failure aircraft would not have made it. Must have been some thrust......

[PJ2]

BGQ - re a/t, ok, thank you. Again, I don't think this is an area of high interest in terms of causes, but merely something to understand.

Bill.Martin;

Unquestionably in mission-critical systems, the design goal is for system, control and indicator independance.

The disturbing aspect of this, apropos your remarks simfly, (and I may have missed other comments already made to this effect) is, both engines "failed", (ok Sir Ralph, "failed to respond") at the same time. This was not a single-"engine" failure - this was an "across the beam" failure involving independant systems - far more disturbing I should think.

Since FADECs are truly independant with their own generator (PMA) and electrical backups for FADECs are part of the design, and since documented engine roll-back behaviours almost always involve only one engine*, the need to examine the "corpus collosum" if I may, of the autothrust system , may be more highly indicated than in other areas of investigation, (and the investigators, I realize, will have comprehended this almost immediately after the initial determination of failure mode(s) ).

ILoadMyself; terrific post - very true, and well stated - tip 'o the hat.

*I found a documented case involving a CFM56 which if nothing else, makes interesting reading for further knowledge on such systems. It can be found at, "TSB Report on Cathay Pacific A340 (http://www.tsb.gc.ca/en/reports/air/2002/A02P0261/a02p0261.asp)"