Jorge R. Frank wrote:
1) Columbia did not carry the RMS on STS-107.


Without a payload to drop off and pick up there was no reason to carry
the RMS.

2) The CAIB addressed the option of an inspection EVA - without the arm -
in Volume 1, Section 6.4, page 173.

Which concerns damage to the TPS if a astronaut tries to climb out of
the cargo bay and under the wing to have a look at things.
However, given where the foam impacted at just under the leading edge of
the wing, a astronaut may have been able to see the damage just by
peeking past the front edge of the cargo bay doors at what the leading
edge of the wing looked like.
Considering the concerns that NASA had shown in the past after things
like chipped tiles on ascent from popcorning of the foam, it's very
surprising that they didn't at least okay a EVA of even that limited
extent after seeing the obviously major foam impact event during ascent.
In fact, the whole reason the ET ended up with that ascent video camera
on its exterior was to record foam shedding events that were causing
unexpected damage to the tiles during ascent, and IIRC that was first
flown two flight before the loss of Columbia
Even more surprising is that they didn't okay a look at Columbia from a
reconsat; that would have completely removed any sort of safety risk
from a EVA, and frankly I find the argument that nothing could be seen
if the impact had occurred where it was thought to have occurred - ahead
of the port landing gear door - unconvincing, considering that once the
black exterior surface of the densified belly tiles was abraded away the
white interior of the tiles would be revealed, giving a almost perfect
optical contrast for detection.

Pat