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From: tcliftonr@cc.curtin.edu.au
Newsgroups: rec.skydiving
Subject: Re: Graph of osc'n due to high windforce
Message-ID: <1991Jun25.194227.8803@cc.curtin.edu.au>
Date: 25 Jun 91 11:42:27 GMT
References: <1991Jun18.150541.5220@rodan.acs.syr.edu> <983@lhdsy1.chevron.com> <1991Jun21.145113.6028@Stardent.COM> <994@lhdsy1.chevron.com>
Organization: Curtin University of Technology
Lines: 18

In article <994@lhdsy1.chevron.com>, yzarn@lhdsy1.chevron.com (Philip Yzarn de Louraille) writes:

> Since we agree that the [extreme high altitude] skydiver's terminal
> velocity is slowing down as he/she gets lower in the atmosphere, how
> could his/her acceleration be greater than g? I don' get it.

The wind force is 16 N/kg upwards, his/her weight is 9.8 N/kg downwards.
So the net force is 6 N/kg upwards, giving a net acc'n of 6 m/s2 upwards.

Just as I feel my weight reaction push back up on my feet at 9.8 N/kg, 
or one gee, this re-entering jumper feels 16 N/kg or 1.6 gee pressing
back up on torso and limbs.  

And it is just that force which will be used for skydiving with 
- for the deliberate accelerations.  We are familiar with about one 
gee of wind force to work with.  But these high-altitude-challengers
will get much more than one gee, up to 16 N/kg, for about thirty 
seconds.  Pioneers!