>Why so fast?  Normal terminal velocity is much slower.
"The last person to try to break the highest free fall record died in
the attempt. In 1965, New Jersey truck driver Nick Piantanida suffered
catastrophic equipment failure when his facemask blew out at 57,000
feet. Lack of oxygen caused such severe brain damage that he went into a
you can discover that he will break the sound barrier at 35,000 m,
presumably reaching top speed somewhere above 30,000.
>>From: fork-admin@xent.com [mailto:fork-admin@xent.com] On Behalf Of
>>Sent: Sunday, September 08, 2002 8:36 AM
>>So uh, would this qualify for the Darwin awards if he doesn't make it?
>>RH> Today a French officer called Michel Fournier is supposed to get
>>RH> 350-metre tall helium balloon, ride it up to the edge of space (40
>>RH> altitude) and jump out.  His fall should last 6.5 minutes and
>>RH> speeds of Mach 1.5.  He hopes to open his parachute manually at
>>RH> end, although with an automatic backup if he is 7 seconds from the
>>RH> ground and still hasn't opened it.
>>RH>   "Vederò, si averò si grossi li coglioni, come ha il re di
>>RH>   ("Let's see if I've got as much balls as the King of France!")
>>RH>   - Pope Julius II, 2 January 1511

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From fork-admin@xent.com  Tue Sep 10 11:07:16 2002

On Mon, Sep 09, 2002 at 11:01:22AM -0700, John Hall wrote:
> Why so fast?  Normal terminal velocity is much slower.
Terminal velocity can be calculated by $v_{T} = \sqrt{\frac{2mg}{CpA}}$
where C is an experimentally determined coefficient, p is the density of the
air, and A is the area of the object. These calculations only work if the
object is blunt and the airflow is turbulent, blah blah blah. Terminal velocity
for a skydiver actually varies with how the diver holds themselves -- you go
faster if you pull yourself into a cannonball. That is the "A", for the
most part.
All else being equal, the terminal velocity is inversely proportional to the
square root of air density. Air density drops off pretty quickly, and I
really should be doing something other than digging up the math for that. I
think it involves calculus to integrate the amount of mass as the column of
the atmosphere trails off. I grabbed the other stuff directly out of a book :).
In '87 a guy named Gregory Robertson noticed a fellow parachutist Debbie
Williams had been knocked unconscious. He shifted so that he was head down,
hit about 200 mi/h, and caught up with her and pulled her chute with 10 seconds
to spare.
--
njl