I wish I had time to stop and discuss the above in more detail, but I am seriously busy at present and not just with flying! I agree with you,
OT and
PP, on the substance of what you guys are saying. As far as I can tell, a primary line of thought on the Board revolves around a breach at RCC 1/2 starting the "chain".
Do remember that the Kirtland shot was taken barely a minute before the total and highly visible disintegration started. Prior to that, whilst still in darkness, several "flashes" had been well observed as she passed across the dark sky. If, as is now being suggested, these were the evidence of zippering from the glove (cuff) rearwards, by the time they snapped her from Kirtland, the leading edge would have been well strippped back.
Tech note: Inconel melts at around 1350ºC, so not
too quickly in that plasma. Any exposed Al surfaces, however, would be melting like cheese. Hence the complexity of the probable heat paths and patterns.
Therefore, that pic, with any additional heat effects described in above posts, would be quite accurate. However, it is not showing the initial cause/source, but merely the final state of Columbia just before she was overwhelmed. Hope that makes sense.
Also, I would just repeat what I have said previously: bear in mind that there was probably more than one damage point (as per previous flights
ad infinitum). This time, unfortunately, it involved the RCC sections. Any
one of them would be fatal. Thus, what did which first is largely academic. The issue remains to stop bits coming off in the first place.
Check out the 1999
Annual Report (sorry - 3.6mb PDF!), and see what they were saying about possible on-orbit damage to the RCC and the proposed fix (search "Inconel"). They were thinking in terms of micro-meteorite damage of up to 0.25" and its catastrophic effect in the wrong place. Not a hunk of debris "
the size of a briefcase". You'll see what I'm getting at. The lower area of the RCC was considered most critical.
Of the three pieces of debris that detach from the ET in the crappy launch video, one which makes a fleeting appearance may have been well inboard, and one appears to strike the underside near RCC 7-9, IMHO.
Really must dash, but will chip in as time permits. God bless pioneers, all.