PPRuNe Forums - View Single Post - AF 447 Thread No. 5
View Single Post
Old 3rd Aug 2011, 12:43
  #1399 (permalink)  
DozyWannabe
 
Join Date: Jul 2002
Location: UK
Posts: 3,093
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by BOAC
I proposed a 'gut feeling' that 15-20,000 ft would have been the lowest practical unstall height to avoid a crash.
Agreed.

This would have meant 1 1/2 - 2 minutes to recognise they were stalled. I also suggested that a pitch change to around 30-40 degrees below the horizon was needed to unstall the wings.
Also agreed. If the "Assiette" trace is reliable, the lowest the nose-down pitch ever got was approx -10 degrees (2:11:55, 32,000ft), but due to a combination of the aggressive up-elevator input and the THS position, this was immediately reversed and nose-down was never successfully maintained for more than around 14 seconds.

This does raise the question of what would have happened if the PF had simply let go of the stick at this point and used rudder to control roll as and where necessary?

I'm reminded of the infamous Aeroflot A310 crash where the relief captain's teenage son was at the controls, unwittingly engaged CWS and banked into a stall. All he (and the crew) had to do to resolve the situation until very late in the sequence was to let go of the controls, and the bank angle protections would have righted the aircraft. Unfortunately the crew had not been fully trained in either aspect of the A310's features in that regard.

Originally Posted by deSitter
I saw on some show about aviation disasters, a German pilot talking about the sidestick, and how there was absolutely no feedback from the airplane and its controls; that inhuman attention to the minutiae of data that is constantly streaming from the instruments was persistently required ... That told me everything I needed to know about Bussism.
Was it Survival In The Sky (aka Black Box in the UK), and was the pilot's name Heino Caesar, perchance? In which case you'd have got a less-biased answer asking Reagan what he thought of Lenin.

If what he said was true then you'd have seen a whole plethora of FBW Airbus crashes by now, and the type would have a significantly worse safety record than others, instead of the near-parity that is actually the case.

Last edited by DozyWannabe; 3rd Aug 2011 at 13:17.
DozyWannabe is offline