View Single Post
Old 23rd Aug 2010, 18:03
  #86 (permalink)  
EXWOK
 
Join Date: Sep 2007
Location: UK
Age: 53
Posts: 124
Also, regarding the 4000psi pressure adopted - the control surfaces most definitely did need powerful actuators; as you now know they were very active, especially on approach and transonic, and as well as IASs of up to 530kts you have all the lever arm changes brought by shifting centres of pressure over the surfaces caused by shockwave movements.

If you want to fly supersonic, frontal area is everything so 4000psi also has the benefit of keeping the PFCU cross-section down.

I'm sure M2Dude will be able to give a better explanation of this aspect - it's nearly seven years since I flew the beast (that's depressing) and it's hard enough to remember detail of the flying bits, let alone the complex engineering aspects.
EXWOK is offline