PPRuNe Forums - View Single Post - AF447 wreckage found
View Single Post
Old 19th Jun 2011, 18:09
  #1788 (permalink)  
RetiredF4
 
Join Date: Jun 2009
Location: Germany
Age: 71
Posts: 776
Received 3 Likes on 1 Post
camber of THS

aquadalte
Chris Scott:
I know you do. When I made my studies, conventional stabilizers were designed to produce negative lift. At that time, there were no preoccupations with fuel saving or drag reductions...
I think (although not sure) that, with the advent of CGCC computers and in order to save fuel, that new big jets suffered a slight redesign of the stab profile. New jets are not designed to be stable. They are designed to fly with near zero trimming. It is therefore a waste of lift and fuel, to design stabs producing negative lift, together with 5 Ton of Fuel...
I will pay closer attention next time I fly and will take a closer look at the stab profile.
No need to wait, look at the pictures Confiture posted in the other AF447 thread.

FBw could not change the laws of physics, if you use cambered airfoils, the lift of the wing has to be upward and that of the tail downward at 0° AOA to have some kind of positive stability, when the confusers go on leave.

Last edited by RetiredF4; 19th Jun 2011 at 19:19.
RetiredF4 is offline