AF 447 Thread No. 8

[PJ2]

mm43;

Thanks for the link. IIRC, the time for the airspeed to return to normal was painfully short...less than a minute? but by that time the airplane was established in the stall. In the original sim exercise, (I did two), it took about 4 minutes to slow down from 270kts to about 186kts, in level flight. At the time I never contemplated the possibility of a pitch-up and it is remarkable how quickly the energy is lost. That said, Owain Glyndwr has posted data which posit a successful recovery as low as 6000ft. He readily acknowledges that few if any transport line pilots would point the airplane down the necessary -10deg pitch to do so but the higher-level scenarios, which still require just a -10deg pitch attitude, recover successfully.

bubbers44;

Indeed, why not just hold 2.5 and make that the target in the drill?

For almost all conditions that would be fine and that is how I have argued - perhaps not "2.5", but the last-known. Clearly it is what all other crews did, to a greater or lesser degree.

What I can see out of this extended conversation is a subtle need to at least protect the airplane from going downhill. What perhaps wasn't anticipated was someone pitching up to 15deg in cruise and that has motivated my argument all along.

To me, and perhaps to most transport pilots, if it started going downhill a bit we'd just bring it back up, hopefully gently, (but that assumes that the altimeters are working!...but there's still the GPS.

Five degrees caters to all weight/altitude conditions, but I know from having looked for years and years at the ACMS data in cruise flight (A330-300) that the pitch doesn't vary much from 2.0 to 3.0 degrees even in the kind of turbulence AF447 was in. So keeping it at 2.5 and then working from there, fine-tuning it just in case that was a transient pitch attitude or power setting, is very doable.

I'm pretty sure we have to look beyond the "cheap new hire pilot" notion here. A great deal of commentary has already been offered by a number of contributors on the topic.