[OT] Space shuttle explosions and computers (was Re: Who invented the internet?)

From: Eric Smith <eric_at_brouhaha.com>
Date: Wed Feb 17 22:49:21 1999

Allison wrote:
> FYI the speed attained at
> that point is some 3600mph far from orbital velocity.

I'm not sure how to parse that. Are you saying that it was traveling at
3600 MPH, which is far from orbital velocity (i.e., a missing comma), or
that it was travelling at 3600 MPH less than orbital velocity?

(In any case, the use of the word velocity is incorrect. Velocity is
a vector, as I had drilled into me in Physics class.)

The NASA reference I posted earlier claims:
        At this point in its trajectory, while traveling at a Mach number
        of 1.92 at an altitude of 46,000 feet, the Challenger was totally
        enveloped in the explosive burn.

The best information I have suggests that the Space Shuttle does not
use the Honeywell DDP-516 in any capacity, and that engine control is performed
by the some of the IOP processors that are part of the IBM AP-101S
computers. The entire AP-101S, including both the GPC and IOP, occupies
about 0.025 cubic meters, masses about 30 Kg, and consumes about 550 W.
A DDP-516 occupies about 2.5 cubic meters, masses about 250 Kg, and consumes
over 1000 W.

The AP-101S replaced an earlier AP-101B computer that was twice the size.
Anybody know where I can find one for my collection? :-)
Received on Wed Feb 17 1999 - 22:49:21 GMT