BA B777 Incident @ Heathrow (merged)

[egbt]

I say again.......the right engine fan blades are plainly visible and still intact. This means the engine was not delivering power when the aircraft and both nacelles hit the ground. Even at idle power one would expect to see the blades stripped by the sudden deformation of the nacelle, such as is plainly evident in the left engine. This suggests the engine may have run down between 600 feet and impact.

Or they pulled the fire handles once over the road?

[Nigel_the_Normal]

My sources tell me that John was duped into making a statement as they had gained access to his Mothers house.

There is a standing instruction not to speak to the press.

[blueoreas]

I just found this interesting.

http://www.imp-detail.org/archive.php?apid=112



Aircraft: B767 Undifferentiated or Other Model
INSTRUMENT MALFUNCTION AUTOPLT ABNORMALITY. CLR OF CLOUDS, FL350, ECON CRUISE 'MACH .78,' SMOOTH AIR. THE FO WAS FLYING THIS LEG WHEN 30 NM NE OF LEFKO INTXN ON GREEN 26 PROCEEDING DIRECT TO REDFIN, JAX CENTER CLRED US DIRECT REMIS FOR A WARNING AREA HAD GONE ACTIVE. AT APPROX XA:44 ENE OF REMISS WE ENCOUNTERED THE EVENT. FIRST THING I NOTICED WAS THE AMBER AUTOPLT AND AUTO THROTTLE EICAS MSG AND AUDIBLE ALERT FOR A DISCONNECT. WE ALSO NOTICED SOLID YELLOW LINES THAT WENT THROUGH ALL FLT MGMNT CTL DATA ON BOTH CAPT AND FO ADI'S AND HSI'S. I LOOKED AT THE TOP EICAS ENG INSTRUMENT AND NOTED NO N1 OR EGT DIGITAL READOUTS, ONLY WHITE CIRCLES REMAINED. LOWER EICAS REFLECTED THE SAME. NO DIGITAL INFO FOR F2, FF, OIL PRESSURE, OIL TEMP, OIL QUANTITY, VIB. BOTH CDU'S WERE BLANK. AN IMMEDIATE CHK OF THE ELECTRICAL PANEL INDICATED NO MALFUNCTIONS, A TEST OF INDICATOR LIGHTS REVEALED NO BURNED OUT LIGHTS. CENTER AUTOPLT WAS ENGAGED AND SHOWING PANEL ACTIVE WITH NORMAL INDICATIONS. STANDBY ADI INDICATED WE WERE STARTING A LEFT BANK. WITH WARNING OF AUTOPLT AND AUTO THROTTLE DISCONNECT I GRABBED THE YOKE AND HIT THE AUTOPLT DISCONNECT SWITCH AND DIRECTED THE FO TO FLY. HE MAINTAINED LEVEL FLT AND STATED THAT THE AUTOPLT WAS STILL ENGAGED. I ATTEMPTED TO DISENGAGE THE AUTOPLT WITH THE DISENGAGE BAR BY PULLING IT DOWN AND WAITING. THE WHITE AUTOPLT CMD LIGHT REMAINED ON. I WENT BACK TO THE YOKE AND AGAIN HIT THE DISCONNECT AND FELT THE YOKE PRESSURE THE FO WAS HOLDING. [Brief synopsis: while flying, an alarm sounded indicating that the autopilot had disengaged itself. The following displays that indicate the status of the aircraft stopped functioning: ADI (Attitude Direction Indicator), HDI (Horizontal Situation Indicator), EICAS (Engine Indication and Crew Alerting System - the acronyms the pilot references on this system are N1 (compressor rotational speed), EGT (exhaust gas temperature), and FF (fuel flow)), CDU (cockpit display unit, a radar display). The pilot performed several system checks which all claimed that equipment was functioning normally. When the plane started making an uncommanded left turn, the pilot attempted to manually disengage the autopilot (which was still operating despite the warning saying it had stopped) but was unable to.] I CALLED ATC AND ADVISED WE WERE HAVING SOME KIND OF AN ELECTRICAL ANOMALY. JUST AFTER THE CALL TO ATC THE AUTOPLT DISENGAGED AND THE WHITE CMD LIGHT WENT OUT AND ALL SYSTEMS RETURNED TO NORMAL OPS. I DIRECTED THE FA 1 TO SEARCH THE ACFT FOR UNAUTHORIZED ELECTRONIC EQUIP BEING USED. I THEN RPTED TO ATC THAT OPS WERE NORMAL. THE EVENT LASTED APPROX 45 SECS. [...] FA 1 RPTED A CELL PHONE WAS IN USE BY PAX. I DIRECTED FA 1 TO HAVE IT TURNED OFF AND CONFISCATED TO ME. PAX STATED IT WAS A NEW PHONE BY AT&T, MODEL SIEMENS CEO168, HE WAS INSTALLING NEW PHONE NUMBERS IN DATA BANK AND NOT TALKING ON PHONE. MAINT WAS CALLED AND STATED THE ACFT HAD NO PREVIOUS HISTORY OF THIS TYPE OF EVENT. ONE AREA OF CONCERN WAS A POTABLE WATER TANK GAUGE QUANTITY PROB. THE FO AND I COMPLETED A COMPLETE SYSTEMS CHK CONCLUDING OPS NORMAL. WITH PASSENGER'S CELL PHONE OFF AND IN MY POSSESSION THE FO AND I AGREED WITH DISPATCHER TO CONTINUE THE FLT WITH CAVEAT THAT SHOULD ANY OTHER SIMILAR EVENT OCCUR WE WOULD LAND ASAP. [...] FROM NAVIGATION POINT REMISS WE PROCEEDED UNEVENTFULLY TO SFO. [...] THE CELL PHONE THAT WAS ON AT THE SAME TIME IS RPTED TO BE A POWERFUL NEW TYPE IN THE SEARCH MODE. THE LOCATION OF THE PHONE DURING THE INCIDENT WAS THE CABIN AT SEAT ROW X WHICH IS ROUGHLY ABOVE THE ELECTRONICS AREA. DURING THE FAILURE THE STANDBY ENG INSTRUMENTS ACTIVATED.

[Hand Solo]

Originally Posted by captwilga

Modern jet engines just don't stop until the fuel supply is cut off and autothrottle/ engine management systems don't either. When was the last time your car engine quit!

Not really a great example. My brother's modern engine managed German car has conked out three times with the same fault. When my different engine managed car went mental the mechanic knew what it was immediately. Just because the MBTF is much higher on an aircraft than a car it doesn't mean the failure won't happen eventually. Unless you can verify that absolutely nothing happened to affect the link between the flight deck and the FADECs I'd steer clear of allusions to fuel starvation.

[Feathers McGraw]

FrequentSLF (and others talking about this aspect)

It's one thing to install Wi-Fi transceivers in an aircraft, and quite another when a consumer-grade product such as a laptop Wi-Fi transceiver is used aboard.

The former kit will be individually tested and be very carefully designed to have very low spurious (i.e. out-of-Wi-Fi-band) emissions.

A laptop might have poor spurious emissions because of a fault in assembly or manufacture, but as this is not tested for 100% of the production runs (it relies on type-approval of a small sample of units) there is ample opportunity for a problem like this to be limited to a single laptop and perhaps to the combination of that faulty laptop and an aircraft with a small defect in screening or grounding of the avionics, perhaps due to wear and tear or a maintenance error.

Note that Wi-Fi is usually not designed with power control of its transmitters (it's short range, so fixed output power is OK) whereas cellular phones are designed to have power steps to maximise the capacity of each cell and to reduce the variation in signal levels at a base station (essential for CDMA systems such as 3G).

The latter suggests that allowing indiscriminate use of Wi-Fi devices is riskier than allowing the use of mobile phones in the air.

[AmericanFlyer]

FADEC Software?

There have been many remarks made about how independent the two engine control systems are:

• Separate power supplies
• Separate computers
• Separate almost everything

However, I believe it is highly likely that both computers were running the same software. If the software were fed the same inputs, and there was an error in the software, they could both output the same erroneous controls to the engines. I'm not saying that this is what caused the crash. What I'm saying is that just because everything appears to be physically separate does not mean that they could not fail simultaneously from the same fault, if that fault is a software fault.

I have worked professionally in the software development business for thirty-eight years, and I have personally seen this very type of software fault cause the failure of many online banking systems. It is very difficult and expensive, but worthwhile, to avoid. Many persons do not realize how dependent their very lives have become on computer software and silicon today.

On the space shuttle, there are three main computers which handle operations and decision-making processes. NASA had them independently programmed in three different languages by three independent teams of software developers, but to the same specifications in terms on inputs and outputs to avoid this very issue. In case of disagreement, two of the three computers could vote to over-rule the third computer output.

[Super VC-10]

No power until 600'. Not permitted under BA's ops. You have to be in the stable configuration normally by 1000' but ALWAYS at 500'. We have a call at 500 with a reply "stable" or "Go Around".

The thing is, if "Go Around" power isn't available (as seems to be the case here) then the book goes out the window, and it's down to seat of pants flying the thing.

Stable at 1000' - Check!
Stable at 500' - nope! Throttles not responding! Hang on to your hats!

[ChristiaanJ]

Originally Posted by RatherBeFlying

I would assume ... a windshear transition that presented it with an airspeed decay. The a/t would then be asking for more thrust which was not obtained.

Windshear AND engine power loss at the same time sounds like a bit too much of a coincidence, especially if loss of power alone is enough to explain what happened. We'll see.

Given the high AOA shown crossing the roadway...

It's still doubtful that phone video actually shows BA038.

[Fugazi1000]

AmericanFlyer.

Very interesting (if a little irrelevant), but what if all 3 computers disagree? Something must arbitrate.

[Nigel_the_Normal]

Flyer

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

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

You people really make me want to puke with your ill informed bull****.

[bsieker]

Electronics, Cameras, Structural Integrity

Originally Posted by 787FOCAL

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

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

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

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

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

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

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

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

Originally Posted by fcom

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

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

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

Originally Posted by slink

The A340 accident was totally different.

(Referring to the Accident at Toulouse-Blagnac)

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

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

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

[pasoundman]

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

Absolutely NO.

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

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

[yakmadrid]

Could not agree more with rubik101.


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

[Contacttower]

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

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

[mocoman]

highly likely that both computers were running the same software

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

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

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

[Hand Solo]

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

[PJ2]

snowfalcon2

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

Nonsense.

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

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

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

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

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

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

[Sallyann1234]

@FrequentSLF

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

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

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

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

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

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

[ribt4t]

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

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

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

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

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

[Nightstop]

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