PPRuNe Forums - View Single Post - AF 447 Thread No. 6
View Single Post
Old 22nd Aug 2011, 21:37
  #332 (permalink)  
A33Zab
 
Join Date: Jun 2009
Location: somewhere
Posts: 451
Likes: 0
Received 0 Likes on 0 Posts
@Machinebird:

In this case probably not. In Alt 2 law, the aircraft is trying to hold a pitch attitude.
Now, that is new information! Any reference?
ALTERNATE is Nz LAW, like NORMAL LAW.
Stick relaxed it will retain 1g, SS deflection is a Δ gee command.

If SS (pitch) remained relaxed after the A/P drop-off event it would not
have been in this upset situation.

For SS (pitch) relaxed:
If you follow the Nz (Normal Acceleration) traces for every Nz above 1g
the elevator would have been deflected ND.
For Nz below 1g the elevator would have been NU to achive the 1g.

So it depends at which time the SS (pitch) was relaxed and you have to
keep in mind that after that the Nz trace would have been very different.

IMHO if altitude did permit this A/C (SS relaxed) would have
been stabilized finaly to normal flight.
A larger and sustained SS ND command (initiating THS to drive to normal value)
would have helped a lot!
A33Zab is offline