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Old 24th Jun 2015, 18:48
  #6344 (permalink)  
John Farley

Do a Hover - it avoids G
 
Join Date: Oct 1999
Location: Chichester West Sussex UK
Age: 87
Posts: 2,206
There would be no theoretical problem to scaling the ramp principle. The practical issues of a large size one are another matter obviously.

However to obtain any real benefit in respect of reduced take off distance when using a ramp you need two things:

1 A flight control system that enables attitude control at speeds well below the normal aerodynamic stall for the aircraft concerned.

2 A minimum thrust weight ratio of around .85 to .9 so that during the limited flight time the ramp gives you (when lift is less than weight) you can accelerate quickly to where the wings alone will let you fly before your vehicle subsides back to the ground.

Sorry a T/W of .25 would rule out any real advantage
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