[sci.space.shuttle] need help with launch times

choinski@primerd.prime.com (10/19/89)

This is the second posting of this message.  I am trying again because I don't
think it made it out the first time.  If it did, please bear with me -- I
have shortened it.
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Does anyone have a "quick and dirty" formula for determining the flight time
to orbit of a shuttle or rocket?  Preferably, something generic that fits
this problem:

/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\
| Assume a vehicle with a thrust/weight ratio of "T".  It takes off in a      |
| horizontal oriention (i.e. like a spaceplane) but quickly noses up toward   |
| a flight path like the space shuttle.  It follows this path to orbital      |
| insertion at an altitude of "A" kilometers above surface and travelling at  |
| the correct orbital velocity.  "A" is very high orbit (13885km if this      |
| helps, but basically "A"=(SQRT(10*g)-1)*r*6420, where "g" is in earth       |
| gravities and "r" is in earth radii).  How long does it take?               |
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Now I do not have access to high-level physics/aeronautical texts.  Any sort
of "rule of thumb" formula will help.  I am only a CS major, so really hairy
math in some of these books would get me nowhere anyways.

If you can help, please mail me your musings at the address below.  If you
happen to also have a time formula for landing time (given an atmospheric
density of "P") I would appreciate it.

Thanks!  I hope someone out there can help.

-============================================================================-
 Burton Choinski                                       choinski@env.prime.com
   Prime Computer, Inc.                                  (508) 879-2960 x3233
   Framingham, Ma.  01701
 Disclaimer:  Hey, not me man; musta been my evil twin.
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