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Old 19th December 2003 | 04:02
  #19 (permalink)  
John Farley

Do a Hover - it avoids G
 
Joined: Oct 1999
Posts: 2,201
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From: Chichester West Sussex UK
Tough T!

Another time then. The big g (up to 3) tends to come with the smaller ramp angles because once the angle starts to increase beyond 10 you get so many ballistic seconds even at max weight you can afford to start from very close to the ramp and so only have 50 kts or so when you hit it.

Initially we could see the gear being bottomed at high weights and high speeds and had ideas of changing the damping of the oleo (rigid would be ideal) to stop any risk of shock loading at the end of its travel. But it turned out not to be necessary. Another win win win thing.

(I'm sure its obvious but normally gear is designed for the landing impact which can be a very big force applied for a very short time which gives high closure rate that is resisted by the dampers. Gears often break on a heavy landing long before the oleo has bottomed for this reason. Change the time of applied force to a second or so going round the ramp and even a much reduced force can bottom the damper)
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