Old 01-26-2008, 04:25 PM
  #11  
KoruPilot
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Joined APC: Mar 2006
Position: Contract purgatory
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You miss the power lever because you are high, hot, 1000 AGL is coming up real quick and you are behind the eight ball. The power lever on the 777 are as wide as the 747 across, there are just two of them.

You see, I just don't get it, and frankly (strike me down if I am, hopefully, dead wrong) I'm not not all together buying it. The only thing that tells me that I am wrong is that the pilot's and the AIB are saying that the engines did not respond to commanded thrust; but I am wondering about exactly what data on the DFDR they (the AIB) are looking at.

Allow me to explain:

The DFDR data tells them that at some point, I understand at around 600 feet, the power did started to advance, but then after three seconds the right power came back, then eight seconds later the left power. This makes absolutely no sense from a technical malfunction standpoint (but I am no engineering expert). What does make sense, as I have over the years seen this type of thing happen on an unstable approach (with previous employers only thankfully), is that the thrust reduced below commanded (A/T) because the pilot physically retarded the power levers.

On approach and with the A/T's armed, as you reduce speed and bring out flap you bug back the command airspeed bug to the next flap setting speed which is nicely represented on the tape. As the speed approaches that setting the Thrust Management Computer tells the A/T's to advance the power. If you are in a big hurry to reduce speed, and you call for the next flap setting just prior to bug speed, the power will start to advance. This is no worries, you just grab the levers and pull them back, the thrust will follow what you are setting over what the TMC and the Auto Pilot FD system think is prudent. The problem with my theory is that as you bugged the speed back to the next setting the commanded thrust would reduce as well. But, if you set that lower flap, then forgot to re-set the command airspeed but (these thing's happen on a regular basis if people are busy and not all together focussed) then the commanded thrust would want to stay up, even increase as the aircraft would require more to fly at that speed, with that flap setting.

The flaps; who in their right mind would reduce flap when below that speed. I'd say nobody. But, if one was high on speed, greater than 170 knots on the 777 with flap 30, then they would blow back automatically and not come back out until the speed had reduced to a lower one. To me, looking at the plane on the ground, the flaps look like they are fully out, but that's probably a stupid thing to say as it is pretty touch to judge. Either way, reducing flap makes no sense, nor does the idea that a pilot would even think that it was a good idea at 600 feet.

There have also been accounts that the plane was maneuvering somewhere on final, which you just don't do at LHR (they have you on the approach way back), and a number of people said that it was very loud as the plane came close to the ground. OK, it'd be pretty loud anyway, but it would be relevant to my wholly unlikely tale here. I have not seen any graphics of the approach course so that's admittedly pretty speculative.

The RAT can been seen but if it was deployed it would have been spinning and the blades would have been gone. They at least look quite intact in the picture.

The left engine at least was spinning at a reasonable rate as all of the fan blades are badly damaged; most looked missing or bent rite back.

Who thought it was a good idea to parade the skipper and co out in front of the public the next day. Likely some management jockey who was previously working for a large car rental agency and went to the pages in their management 101 book labeled "damage control". Also, as BALPA so furiously told the BA management that this was a grand example of why they should continue to only have BA pilots fly all BA planes, as they are so very skilled, the day of the accident. . . well, if I was BA management and I wanted to put a nail in that one, and I knew thing's were not as simple as being made out, perhaps I'd put the pilots in the public spotlight so as to more easily hang their butts out in the wind when it all came crashing down in the future.

But perhaps I am a bit paranoid. That would mean of course that two separate systems failed to respond when told to do so by everything, which is something that has never happened before on how many flights; basically one in a billion. And, it would all have to happen at 600 ft on final. Just just makes no sense, but I hope there is some weakness in the system that allowed this to happen, I really do. After looking at LOSA and IOSA numbers regarding unstable approaches it does make me wonder. Let's all hope I'm an idiot shall we.
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