In article ,
Mark Percival wrote:
Would it have been possible for the o-ring to burn through on the other
side of the SRB (ie: away from the tank)? Was it just bad luck it burned
through where it did?

Not entirely just bad luck. The SRB rear attach struts put extra stress
on that area of the casing, tending to pull the joint farther open there.
Transient loads from the struts during ignition probably contributed to the
initial leak and likely O-ring damage there; transient loads during
windshear shortly before the accident probably re-opened the leak.

The joint design was generally a poor one, with margins particularly thin
in the conditions of that launch, and a leak could have happened anywhere,
but that particular area was predisposed to it.

If the above is possible then what would the effect had been on the
remainder of the rise to orbit? Would the Challenger been destroyed
anyhow?

Had the leak been elsewhere, there would have been some chance of
survival. The **** hit the fan not because of the leak itself, but
because of the stream of hot gas playing on the attach struts and the ET;
more or less simultaneously, (a) the struts failed and the SRB pivoted
around its forward attachment, so its nose mashed in the side of the ET,
and (b) the ET aft dome tore loose. So the ET disintegrated, and the
orbiter was thrown violently out of control at Mach 3 and broke up. The
failing SRB stayed pretty much intact until Range Safety blew it up some
seconds later.

If the struts had held and the ET not been exposed to excessive heat, the
SRB would have stayed in one piece for a while, perhaps long enough. If
the leak was in a position where it didn't damage the orbiter wing, then
there could have been problems with side thrust from the leak, and from
forward thrust falling off because of the gas lost to the leak (the
shuttle can't cope with any substantial difference in thrust between the
two SRBs), but there was a chance.

If not then would have one of the abort modes been called after SRB
burnout? How bad would the gasses leaking pushed it off course?

Hard to say. It might even have been possible to carry on to orbit.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |