On Thu, 28 Jul 2005 08:20:52 GMT, John Horner
wrote:

Indeed. In the modern world of design, closed loop systems based on
sensors and real-time correction loops along with telemetric datalogging
and analysis are standard ways of designing high end systems. Little
of this was feasible in the days when the shuttle was first designed and
I doubt that it was put fully into place are the decades of retrofitting
and tinker.

You are joking, aren't you? Closed-loop systems were first flown in
the '30s (Lawrence Sperry and his wing leveler), although they'd been
used on steam engines long before that, being as old as the railways.

The '50s X-15 was fly-by-wire and had a finite-state machine for its
FCS. Apollo used a digital FCS, as did the F-8 DFBW airplane. The
DFBW used Apollo computers for the original flight phase and Orbiter
computers for the second flight phase. The LLRV/LLTV FCS was analog,
though.

Mary

--
Mary Shafer Retired aerospace research engineer
We didn't just do weird stuff at Dryden, we wrote reports about it.
or