BA 777 "lands short" at Heathrow

[Spooky 2]

Yeah...and it had some 100 tonnes of fuel when it left Beijing.

What matters is how many tonnes of fuel it had when the engines spooled down.

My guess is ZERO tonnes.

Hey woody with all your experience why don't you just call them up and tell them how it was. What a fooking idiot you are. BTW how much time do you have in the 777 or anyother Boeing ailiner for that matter?

 

[ForgedBlade]

That's a very good observation and does throw a different light on the subject. Here is another one. If the crew had the two crossfeeds open to balance fuel thay may have run a wing tank dry and in turn flamed out both engines at once. Boeing does not approve of fuel balancing during this phase of flight and in addition the aircraft is not very susceptible to any out of balance fuel condition. There may be some sort of an EICAS warning for this fuel config during landing but I cannot recall. Nothing more than pure wild ass speculation at this point so I guess we should stand back and let the pros sort it out.

You can leave the X-Feeds open during landing and even run one tank dry and it won't matter. It's the 777, not a 737! Wait until the final report comes out!

 

[Prog 2/2]

Nice pic in the avatar. Looks 'analog', and real.

Yea, my bit is since the pilots said (in the AAIB statement) the autothrottles commanded a thrust increase and it didn't happen, and then they applied the thrust levers forward and it didn't happen,
presumably while the engines were failing,
that the A/C had some sort of autothrottle failure (power loss to them) or electronic fuel system failure of some sort. If the autothrottles failed or lost power would they disconnect automatically or not? If this happened would the engines fail? Would you be able to use the thrust levers manually if the autothrottles failed or lost power? Thanks 777 drivers.

Lots of conclusion jumping going on here.

First, you presume the engines failed, or were failing. There's nothing in the AAIB prelim that even hints at the engines failing. Not responsive to a thrust lever input is not the same as failing.

Second, where do you get the idea that the A/T system failed? The prelim clearly states that the A/T were calling for an appropriate increase in thrust that didn't materialize. The A/T is just a servo (or two) that moves the throttle lever to specified angle based upon the inputs from a bunch of different sources. If the power to drive the servos quits(which has not yet been proven in this case), then big deal, you just move the T/L by hand as you've always done. No A/T doesn't mean no engines.

Wth that said, an electronic glitch that impedes the ability of the engine EEC's to meter the proper amount of fuel based on the T/L angle is a different story.

 

[Papa Woody]

Hey woody with all your experience why don't you just call them up and tell them how it was. What a fooking idiot you are. BTW how much time do you have in the 777 or anyother Boeing ailiner for that matter?

Why does my experience in a 777 matter?

I am not claiming any special knowledge behind my conclusion that the MOST LIKELY explanation for this accident is fuel exhaustion.

That is: the engines, electrical system, A/T's, etc., were operating normally. And the engines did what engines do when they stop receiving fuel!

Those 108-inch fans suddenly became a liability out there in the London fog as they defied the thrust-lever-angles, instead defiantly milling the wind.

Of course, my primitive C-150 on mogas lacks the technological wizardry to keep its engine operating without fuel: maybe someone on this board with 777 or other Boeing experience could explain how Boeings are designed to run without gas.

If I were speculating about some obscure "cross-feed during landing, EICAS message, A/T-commanded-but-not-delivered thrust lever angle computer glitch", then you could conceivably question my time-in-type-or-manufacturer-model.

But regardless, we all know what most likely occurred.

And thanks for the insult!

 

[Spooky 2]

Why does my experience in a 777 matter?

I am not claiming any special knowledge behind my conclusion that the MOST LIKELY explanation for this accident is fuel exhaustion.

That is: the engines, electrical system, A/T's, etc., were operating normally. And the engines did what engines do when they stop receiving fuel!

Those 108-inch fans suddenly became a liability out there in the London fog as they defied the thrust-lever-angles, instead defiantly milling the wind.

Of course, my primitive C-150 on mogas lacks the technological wizardry to keep its engine operating without fuel: maybe someone on this board with 777 or other Boeing experience could explain how Boeings are designed to run without gas.

If I were speculating about some obscure "cross-feed during landing, EICAS message, A/T-commanded-but-not-delivered thrust lever angle computer glitch", then you could conceivably question my time-in-type-or-manufacturer-model.

But regardless, we all know what most likely occurred.

And thanks for the insult!

Fuel starvation ceratinly could have been the problem and I simply don't have the answer at this hour. My experience in the 777 is limited to about 3,500 hours and some significant training experience at both the airline I worked for and Boeing. I'm most troubled by the fact that neither Boeing nor BA has has any type of fleet inspection stand down which one would have expected if there was a known aircraft mechancal issue. Your attitude on the other hand is simply that of a pitiful observer with no acknowledged information regarding how the airplane operates much less how BA crews are trained, dispatched, or for that matter anything operational other than he must have run our of fuel. Forgive me if I'm wrong about your qualification to speculate on this accident as if there is something I'm missing, shame on me, otherwise, please.......

 

[michael707767]

Fuel starvation ceratinly could have been the problem and I simply don't have the answer at this hour. My experience in the 777 is limited to about 3,500 hours and some significant training experience at both the airline I worked for and Boeing. ..

question for ya. What is the standard flap setting for landing in a 777, 25 or 30? Also I read somewhere that the procedures for most if not all airlines require the use of autothrottles all the way to landing, whether or not it's an autoland. Is that true?

 

[poppi]

Learmount suggested, however, that water could have got into the fuel, frozen at high altitude, thawed as the plane came into land and caused a slush in the tanks. This may have blocked fuel to both engines. Reports yesterday suggested that BA ground staff were warned to check the fuel mix in all its 777s.

 

[Hvy]

question for ya. What is the standard flap setting for landing in a 777, 25 or 30? Also I read somewhere that the procedures for most if not all airlines require the use of autothrottles all the way to landing, whether or not it's an autoland. Is that true?

No...it's not true.

 

[Filkster]

I'll go with an electrical interruption causing a loss of signal to the fadec followed by the gear coming down causing some kind of boeing sofware subroutine to decide the thrust levers are not working and commanding the engines to do whatever they are programmed to do in that situation.

RF
Lets keep Bill Gates out of Aviation.

http://news.sky.com/skynews/article/0,,30400-1301161,00.html

 

[Spooky 2]

No...it's not true.

Sorry Heavy but it is true. The Boeing FCTM states that the AT's should be used for all landings, hand flown or AL. This is a departure from thre B757/767. I don't have my manuals in front of me at this hour but I can quote Chapt. and verse out of the FCTM later today if need be.

Normal landing flaps are 30. Alternate landing flaps are 25. 1 EO flaps are 20 but if you have already gone to 30 and then lose the engine you can do a 30 flap landing. AL are done with 30 only. The airplane is capable of AL with an engine out. BTW, I don't any of this has anything to do with the BA accident.