PPRuNe Forums - View Single Post - Cirrus descent rate under parachute less with wind?
Old 5th Apr 2020, 12:30
  #42 (permalink)  
PDR1
 
Join Date: Nov 2015
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Originally Posted by Fl1ingfrog
"So you don't reduce the impact force - you increase it. As you say in your second statement."

This is of course is true but how the impact is absorbed is important.
This is true, but lateral velocity doesn't change how the vertical force of impact is experienced. The only thing that affects that is the vertical elasticity of the collision - how rapidly the vertical velocity is reduced. Being dragged sideways won't change that. Really chaps - this isn't rocket surgery, it's less than A-level physics or maths. It really is depressing how limited the grasp of basic mechanics can be...

The parachute analogy misunderstands what's going on. The reason why a parachutist is less likely to be injured when there's a wind is simply that it more or less forces a rolling impact. In flat calm conditions there is a strong tendency to try to absorb the impact with just bent knees because rolling feels unnatural without extensive training.

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