PPRuNe Forums - View Single Post - AF 447 Search to resume (part2)
View Single Post
Old 8th May 2011, 22:40
  #956 (permalink)  
takata
 
Join Date: Jun 2009
Location: Paris
Posts: 691
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Machinbird
But all very dependent on power setting. If my aircraft had just lofted me to the edge of space, I would put the throttles wherever the engines seemed happiest just to keep them running and the lights and hydraulics available.
I understand that this is for the zoom part of your scenario.
But what about the boom part of it?
Would you keep full throttles, once having already a very large AOA exceedance , and all your way down during about four minutes?
from, say 40,000+ feet down to sea level?

Originally Posted by Machinbird
Do you have specific data on engine operating envelope-Olivier? I wouldn't be surprised if the engine authorized envelope would be exceeded, but the stall margin envelope is typically very dependent on power setting.
Not at hand.
But say 50-60 degrees AOA without much forward speed remaining at all (in order to stay into your 8000 m zone) will make such an angle for the airfoil to bypass in order to reach the compressors that I really doubt of the tolerance. I'm not even talking about all the tropical storm ice/water you will ingest at lower than cruise levels in the process.

Originally Posted by Machinbird
And without Direct Law, I don't think a deeply stalled Airbus has a hope of recovery. It is a THS thing.
What make you think Direct Law may be lost?
The rudder would be still limited (could be an issue at low speed for stall recovery) but other surface control would still move freely.
takata is offline