PPRuNe Forums - View Single Post - Maximum Landing Impact
View Single Post
Old 28th November 2006 | 08:42
  #6 (permalink)  
chornedsnorkack
 
Joined: Aug 2005
Posts: 834
Likes: 0
From: Estonia
Originally Posted by A-3TWENTY
In the company I am flying for there was a hard landing reported with 2.1G . What´s the equivalence in FPM ?
Cheers
There is not, and cannot be, equivalence between g-s and fpm.

The reason is the following: a plane touching down at some fpm has to be decelerated to zero rate of descent resting/rolling on the ground (here omitting the case where the rate of descent is nonzero when rolling on a sloping surface). The rate of descent is not stopped instantly (this would require infinite force) - it is stopped over extended timespan, while the aircraft continues descending at a decreasing rate - and the length of the landing gear is decreasing.

If the landing gear does not travel a long distance, low descent rates would generate substantial g forces.
chornedsnorkack is offline  
Reply