
“Shuttle
Columbia Mission…” A weird mental slip has occurred here, as surely every spaceflight enthusiast knows that Columbia, the first of the STS orbiters to fly into space, met a fiery end during reentry on 1 February 2003. STS-121 is being flown by
Discovery.
Though it’s tempting to criticize NASA leaders for going ahead with STS-121 before fully solving
the external tank insulating foam shedding problem that led to Columbia’s loss – a policy of proceeding when potentially critical defects were known to exist has been shown to be responsible for the loss of both Challenger and Discovery, 2/5 of the total flightworthy fleet, and a huge blow to public and commercial acceptance of the system – this time, I believe they’ve made a correct choice. Key to accepting the risk of flying before the foam shedding problem is corrected is that STS-121 is that, unless Discovery fails to achieve her planned orbit, she’ll rendezvous with the ISS. EVAs are planned to inspect her leading edges and tiles for damage, and if sever damage is found, the crew will be left on the ISS until Atlantis can be flow to return them (likely 9/2006 or later). It’s unlikely that such damage could be repaired, but at least loss of life would be avoided.
It’s saddening to me that late 2010 will likely see the last flight of a winged, runway-landing spacecraft for some time to come. NASA’s next manned system,
”Project Constellation”, which it appears will be a 3-6 person, modernized Apollo-like system, seems a step backward from the 8+ person shuttles, even though Constellation’s “CEV” is planned to have much greater flight capabilities than the shuttle – slightly better than the 35-year-old Apollo system. The Constellation CLV+CEV system will be about 1% reusable (by mass), compared to the shuttle nearly 99%.
I can’t help but speculate that the extended leadership of NASA – a group including the US Legislature and Executive – isn’t being backward, and, for lack of a better description, a bit
nostalgic in their thinking. While the STS ultimately fell short of its design goals of a highly economical and reliable “space truck”, the CLV+CEV system doesn’t even have the goal – IMHO, it’s just “what Apollo would have look like if it’d been done in the 2010s”. Having been burnt (absolutely no pun intended) by the difficulties of highly reusable systems (the shuttles) and having to date failed to achieve a successful single-stage-to-orbit design, US spaceflight leadership appears to be retreating to a comfortable, proven design, reminiscent of NASA’s glory days.
Perhaps the private sector – or China, or some nation no one expects - will dare where NASA dares no longer. Perhaps NASA will regain its institutional nerve. For an American born in 1960 who joyfully assembled a plastic model of every manned spacecraft NASA has flown, these seem somewhat downbeat times.
Edit: Like the shuttle, the CLV's solid-rocket boosters are recoverable, so the system's reusability by mass is actually about 3%, not 1%.
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