In article ,
(ed kyle) wrote:

I read the CAIB report several times. After "eliminate shedding
from ET", the No. 2 recommendation was to increase the shuttle's
ability to sustain debris damage.

That's all well and good and in principle, it's an excellent idea for
spacecraft to be damage-tolerant for entry. The biggest problem with
that recommendation vis a vis the STS orbiter is that it is an
already-existing vehicle built to meet a myriad of design
specifications and requirements. Adding a new requirement ("The
shuttle orbiter shall be capable of withstanding impacts . . . ")
which directly contradicts a basic design premise for the entire stack
("There shall be no debris shedding . . .") seriously complicates and
already-complicated situation. That's why the CAIB made
"recommendations" along these lines rather than making them hard and
firm rules for return to flight.

One of the long-term goals
was to increase the orbiter's ability to re-enter Earth's
atmosphere even with minor damage. The photos show that neither
of these "toughen up the orbiter" recommendations have been
addressed.

That's what all the various on-obit inspection and repair techniques
(which Jon and others have posted about numerous times) are designed
to address.

- Ed Kyle

--
Herb Schaltegger, B.S., J.D.
"Never underestimate the power of human stupidity."
~ Robert A. Heinlein
http://www.angryherb.net