Terminal Velocity

Mark sez:
}The accepted terminal velocity for a falling human body is
}around 120 MPH (200 kph).

While high drag jump suits allow lower speeds. (90Mph)

Hmm... those figures still seem fairly close.  What do you mean
by 'accelted terminal velocity'?  Is that a person wearing a
streamlined suit in a tucked down position?  If it is, then I
can see the 200kph speed being relevant for grav belt travel.
After all, a person in a grav belt is trying to travel as fast
as possible, and a parachutist is trying to travel as slowly as
possible.  (To allow for better aim, and safety)

The documentary I was referring to was an interview with the
guy Mark spoke of however (Capt. Kittinger)  In the interview he
claimed that he had indeed gone supersonic.  Now, Mark's source
of data sounds much more precise than the rather sensationalistic
documentary I saw, but I find the discrepancy rather disturbing.
After all, there was the guy telling how he went supersonic,
without an aircraft.  Now, Mark sez he only hit Mach 0.9.  :-(

However, Mark does say that at his highest velocity, he did have
a 6 foot drag 'shute out which may have kept him from actually
hitting Mach 1.  Thus, it seems to me that it could indeed be
*theoretically* possible for a person in a grav belt (and a thin
atmosphere) to actually go supersonic.

Catie:
Drag is a non linear function as the velocity of travel
approaches the speed of sound.  I'm no aerodynamics jock, but if
I recall, the non-linear terms build up around the speed of sound
and then drop off.  The function is discontinuous at the speed of
sound.

Thus, you need a certain amount of thrust to get to the speed of
sound and then once beyond it, less thrust is needed to maintain
speed.

Halliday and Resnick are dealing with nice sophomore physics
students who don't have to worry about supersonic stuff.  :-)

Scott "2G" Kellogg
(Then again, *MY* fave freefall bit was Col. Coon in
_Dr. Strangelove_!  Talk about *TERMINAL* Velocity...
WAAAHOOOOO!!! :-)