Columbia investigation update for February 16-22

The investigation into the reentry breakup of STS-107 continued to garner coverage this week. Audio recordings of the last few minutes of transmissions between the doomed shuttle and NASA controllers were released (NYT). Authorities continued to request the participation of the public, both as potential sources of unaired photographic data and in the search for fragments of the shuttle.

It appeared certain that the craft’s disintegration had begun by the time the shuttle was over California (NYT). No debris from that far west has yet been located.

NASA added non-NASA personnel to the investigative panel amid concerns that the original constituents were all too closely linked to the space agency (NYT).

In a peripherally-related development, on Thursday, NASA released basic specification requirements for a shuttle replacement, a four-person space plane.

By February 14, The panel had released a preliminary determination that concluded a small rupture in the shuttle’s left wing had allowed superheated plasma to enter the structure of the wing on re-entry and led to the temperature readings and eventual structural failure (NYT).

As the week began, serious consideration of an orbital impact with space junk, the results of the past few decades of spaceflight launches, was highlighted as a possible cause of the posited hole. Impacts with even very tiny particles at orbital speeds have long been known to pose a threat to spacecraft.

By week’s end, however, it had been reported that investigators were returning to an examination of the external fuel tank insulating foam which was seen to strike the wing at liftoff. Charges had emerged of off-the-books maintenance performed by subcontractors to the foam, and NASA had begun to examine alternative methods for applying and maintaining the insulation prior to the flight (NYT).

As I write this, an AP report disclosed that a Boeing-authored analysis of the liftoff incident states that three chunks of foam, not the single one previously reported, were observed to have impacted the orbiter. The report is “dated eight days before the spacecraft broke apart Feb. 1 over Texas.” Much to my irritation, the Yahoo! link content changed after I wrote this. Here’s a link to the story on an AP wire subscriber’s site – maybe it will hold still long enough to be read.

The New York Times reported “NASA Had Planned Changes on Shuttle Foam” on Thursday, and also “Disagreement Emerges Over Foam on Shuttle Tank” on Friday. This latest story alleges that the foam, if cut or unsurfaced, can absorb water and therefore, the chunk seen to hit the wing could have been denser than NASA has estimated. The Times’ coverage, which so far has been excellent, is rounded up here, although this may be a transient link as the naming scheme is not subject specific, and as I recall, it looks very similar to the 9/11 roundup URL.

Spaceflight Now ran an article noting that the main fuselage of Columbia remained intact for “at least a half-minute” following the last voice transmission from the craft, and also introduced a round-up of their own, the Investigation Status Center. The site also noted the probable location of the wing breach, and reported that investigators have indeed seen U. S. Air Force imagery taken from high-powered telescopes based in Hawaii.

Alas, I still haven’t found my mythical NASA blog (now, of course, this entry will appear in the searckh i just linked). Space folks, if you know where such a thing might be, pass it along!