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Wednesday, July 6, 2011

Was the Space Shuttle a Mistake?


Shuttle assembly: NASA’s first space shuttle, Columbia, was assembled at Kennedy Space Center in Florida in November 1980. It completed 27 missions before breaking apart during reentry into Earth’s atmosphere in 2003.
Credit: NASA

COMPUTING


The program's benefits weren't worth the cost—and now the U.S. is in jeopardy of repeating the same mistake, says a leading space policy expert.
  • BY JOHN M. LOGSDON
Forty years ago, I wrote an article for Technology Review titled "Shall We Build the Space Shuttle?" Now, with the 135th and final flight of the shuttle at hand, and the benefit of hindsight, it seems appropriate to ask a slightly different question—"Should We Have Built the Space Shuttle?"
After the very expensive Apollo effort, a low-cost space transportation system for both humans and cargo was seen as key to the future of the U.S. space program in the 1980s and beyond. So developing some form of new space launch system made sense as the major NASA effort for the 1970s, presuming the United States was committed to continuing space leadership. But it was probably a mistake to develop this particular space shuttle design, and then to build the future U.S. space program around it.
The selection in 1972 of an ambitious and technologically challenging shuttle design resulted in the most complex machine ever built. Rather than lowering the costs of access to space and making it routine, the space shuttle turned out to be an experimental vehicle with multiple inherent risks, requiring extreme care and high costs to operate safely. Other, simpler designs were considered in 1971 in the run-up to President Nixon's final decision; in retrospect, taking a more evolutionary approach by developing one of them instead would probably have been a better choice.
The shuttle does, of course, leave behind a record of significant achievements. It is a remarkably capable vehicle. It has carried a variety of satellites and spacecraft to low-Earth orbit. It serviced satellites in orbit, most notably during the five missions to the Hubble Space Telescope. On a few flights, the shuttle carried in its payload bay a small pressurized laboratory, called Spacelab, which provided research facilities for a variety of experiments. That laboratory was a European contribution to the space shuttle program. With Spacelab and the Canadian-provided robotic arm used to grab and maneuver payloads, the shuttle set the precedent for intimate international cooperation in human spaceflight. The shuttle kept American and allied astronauts flying in space and opened up the spaceflight experience to scientists and engineers, not just test pilots. The space shuttle was a source of considerable pride for the United States; images of a shuttle launch are iconic elements of American accomplishment and technological leadership.
In control: NASA workers disconnect and dismantle Endeavour’s cockpit. The shuttle completed its final mission on June 1 and will be displayed at the California Science Center in Los Angeles.
Credit: NASA
But were these considerable benefits worth the $209.1 billion (in 2010 dollars) that the program cost? I doubt it. The shuttle was much more expensive than anyone anticipated at its inception. Then-NASA administrator James Fletcher told Congress in 1972 that the shuttle would cost $5.15 billion to develop and could be operated at a cost of $10.5 million per flight. NASA only slightly overran development costs, which is normal for a challenging technological effort, but the cost of operating the shuttle turned out to be at least 20 times higher than was projected at the program's start. The original assumption was that the lifetime of the shuttle would be between 10 and 15 years. By operating the system for 30 years, with its high costs and high risk, rather than replacing it with a less expensive, less risky second-generation system, NASA compounded the original mistake of developing the most ambitious version of the vehicle. The shuttle's cost has been an obstacle to NASA starting other major projects.
But replacing the shuttle turned out to be difficult because of its intimate link to the construction of the space station. President Reagan approved the development of a space station in 1984, but the final design of what became the International Space Station (ISS) was not chosen until 1993. The first shuttle-launched element of the ISS was not orbited until 1998. It took 13 years to complete the ISS. Without the shuttle, construction of the ISS would have been impossible, leaving the U.S. with little choice but to keep the shuttle flying to finish the job. This necessity added almost two decades and billions of dollars of cost to the shuttle's operation. Whether the shuttle is ultimately viewed as successful will in large part be tied to the payoffs from the space station that it made possible. It will be years before those payoffs can be measured.
I have previously written that it was a policy mistake to choose the space shuttle as the centerpiece of the nation's post-Apollo space effort without agreeing on its goals (Science, May 30, 1986).
Today we are in danger of repeating that mistake, given Congressional and industry pressure to move rapidly to the development of a heavy lift launch vehicle without a clear sense of how that vehicle will be used.  Important factors in the decision to move forward with the shuttle were the desire to preserve Apollo-era NASA and contractor jobs, and the political impact of program approval on the 1972 presidential election. Similar pressures are influential today. If we learn anything from the space shuttle experience, it should be that making choices with multidecade consequences on such short-term considerations is poor public policy.
John M. Logsdon is professor emeritus at the Space Policy Institute, George WashingtonUniversity, and author of John F. Kennedy and the Race to the Moon. In 2003, he was a member of the Columbia Accident Investigation Board.

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