For anyone interested:
If you go to the tech log forum, you will find the following point excerpted from the BEA report.
The UAS (Unreliable AirSpeed) procedure memory item of turning off the FD's was not accomplished. (FD = Flight Director).
There are even some handy pictures and graphs that show when the FD was receiving good data, and when it wasn't. Mind you, neither pilot was aware of when it was good and when it was bad, but given the procedure as stated, they should not have needed to.
This opens the question: was the PF using FD as a reference, or a primary reference for his instrument scan, even though it was not being reliably sourced by the data it is usually fed?
The reasons behind that might be habit, might be training, might be a lot of things. One of the things CVR's and FDR's don't do is read minds, so one can only guess at that. I think he at various times tried to follow the FDR. I am not on perfectly solid ground in that estimation.
For Sassypilots wife:
The Tech Log discussion features no small number of pilots who post there: gums, Machinbird, PJ2, Retired F4, CONFiture, Clandestino, bubbers44, and numerous others. I discuss things there now and again, though I have not flown much of anything in a few years, and never flew heavy metal ever. I have flown and taught flying in multipiloted aircraft, taught instruments, and instructed in simulators where you try to work a crew very hard to see how strong their systems knowledge and airmanship are. I have also investigated mishaps, including mishaps with fatalities.
I would point out that Tech Log is now where ALL of AF447 threads resides, which John T has kindly explained in the preface to the various threads.
The first three IIRC started on the R & N forum.
Rockhound
What about the following remedy for the situation?:
throttling back one engine to force a wing drop, to drag the nose out of its 40-degree up angle into a dive.
Not a good idea. See below.
SLFinAZ, Indeed,
jcj - Rockhound's 'pilot' was talking out of his seat cushion.
Actually he was entirely correct.
Not so much. He missed a fundamental detail: the difference between pitch angle and angle of attack.
So...in the early stages of the upset the statement is entirely correct...
The pilot in question was advocating this method of recovery for the last two minutes of flight, i.e. when AF447 was deep into the stall.
Not quite.
According to the FDR, the nose wasn't 40 degrees up, ever. It was somewhere around 15 degrees up, more or less, at its peak. The AoA, while there was more airspeed, began somewhere between 4 and 6 degrees as the aircraft neared and entered stall (it seems to have been a dynamic event so maybe stall AoA was passed a few degrees higher). Note that even with a roughly fixed pitch, (more or less 15 degrees) the plane slowed AND the AoA increased as airspeed decreased. This should not surprise any pilot who has done stall training.
Based on the analysis of the pitch angle and airspeed, AoA got upwards of 40 degrees as the plane went more deeply into the stall.
Sooo, Rockhound .... maybe that pilot you referenced ought to make sure he understands the problem before he suggests a solution.
Case One
Could any of you professionals here explain what knowledge of flight physics is taught to pilots in their training
Originally Posted by Clandestino
This: CDBDA AADCD BAADC CADCB BABCD AACDB BACDA. I kid you not
What?
He was explaining how to answer a multiple choice test on flight physics.
I laughed.
I have found the tech log discussions, though full of some chaffe, to have a lot of good nuggets.
I find this thread, after three years of learning about AB, AB330, FBW, sidesticks, control laws, and a few other things, somewhat entertaining.
Mind you, it is also filled with chaffe.
Fly safe. Fly the plane.