Criticism of The Space Shuttle Program - Retrospect

Retrospect

While the system was developed within the original cost and time estimates given to President Richard M. Nixon in 1971, the operational costs, flight rate, payload capacity, and reliability have been much worse than anticipated. A year before STS-1's April 1981 launch, The Washington Monthly accurately forecast many of the Shuttle's issues, including an overambitious launch schedule and the consequent higher-than-expected marginal cost per flight; the risks of depending on the Shuttle for all payloads, civilian and military; the lack of a survivable abort scenario if a Solid Rocket Booster were to fail; and the fragility of the Shuttle's thermal protection system.

In order to get the Shuttle approved, NASA over-promised its economies and utility. To justify its very large fixed operational program cost, NASA initially forced all domestic, internal, and Department of Defense payloads to the shuttle. When that proved impossible (after the Challenger disaster), NASA used the International Space Station (ISS) as a justification for the shuttle. Some speculate that, had NASA avoided the Shuttle program and instead continued to use Saturn and commercially available boosters, costs might have been lower, freeing funds for manned exploration and more unmanned space science. In particular, NASA administrator Michael D. Griffin argued in a 2007 paper that the Saturn program, if continued, could have provided six manned launches per year — two of them to the moon — at the same cost as the Shuttle program, with an additional ability to loft infrastructure for further missions:

If we had done all this, we would be on Mars today, not writing about it as a subject for “the next 50 years.” We would have decades of experience operating long-duration space systems in Earth orbit, and similar decades of experience in exploring and learning to utilize the Moon.

Some had argued that the shuttle program was flawed. Achieving a reusable vehicle with early 1970s technology forced design decisions that compromised operational reliability and safety. Reusable main engines were made a priority. This necessitated that they not burn up upon atmospheric reentry, which in turn made mounting them on the orbiter itself (the one part of the shuttle system where reuse was paramount) a seemingly logical decision. However, this had the following consequences:

• a more expensive 'clean sheet' engine design was needed, using more expensive materials, as opposed to existing and proven off-the-shelf alternatives (such as the Saturn V mains);
• increased ongoing maintenance costs related to keeping the reusable SSMEs in flying condition after each launch, costs which in total may have exceeded that of building disposable main engines for each launch;
• less absolute tonnage available to be lifted into space, since the mass of the SSMEs attached to the orbiter necessarily cut into the craft's 'payload budget' (more payload launched at any one time, by definition, reduces launch costs per pound).

A concern expressed by the 1990 Augustine Commission was that, "the civil space program is overly dependent upon the Space Shuttle for access to space." The committee pointed out, "that it was, for example, inappropriate in the case of Challenger to risk the lives of seven astronauts and nearly one-fourth of NASA's launch assets to place in orbit a communications satellite."