NASA Approves Shuttle Launch over objections

NASA Administrator Mike Griffin has affirmed the decision to launch the STS-121 Shuttle mission in the window beginning 1 July. During the Flight Readiness Review needed to approve the mission, both the Office of the Chief Engineer and the Safety Office registered objections. They felt the possible loss of insulting foam from the brackets holding external lines in place on the external tank (ET) - brackets that had been shielded from the turbulence of launch by the now-removed protuberance air-load (PAL) ramps - was a danger not yet mitigated.

Griffin said of the dissenters: "Looking at their specific discipline areas, they would recommend that we stand down. But there are larger considerations. If we stand down, now we back up station assembly flights. One of the areas that surfaced during the CAIB (Columbia Accident Investigation Board) investigation was the issue of schedule pressure on NASA. Now schedule pressure for us is a fact of life, but it has to be balanced. I do not want to make decisions today which are going to result in having all the schedule pressure in creating station assembly in the last year or two." Griffin did acknowledge the stakes involved: "If we lost another vehicle I will tell you right now that I would be moving to shut the program down."


COMMENT: While I've noted before I am not a technical expert on the Shuttle, this decision has a very bad feeling to it. The admission that schedule pressure does matter, even though Griffin couched it in terms of making sure NASA had a workable flight rate between now and the program end in 2010, is sure to make some Shuttle veterans very concerned. According to an article in Spaceflightnow.com (which also has a longer version of Griffin's comments), loss of foam on the ice/frost ramps appears in NASA's risk matrix in a box labeled "probable/catastrophic." (See http://www.spaceflightnow.com/shuttle/sts121/060617july1/). All I can say as a believer in human spaceflight is that I hope for a safe flight, but I wish I could say I felt confident of it.