The dismal economic record of the space shuttle is well known. The safety flaws in the shuttle’s design are not as well known. When the first shuttle disaster hit seventeen years ago, we wrote the following letter in an effort to get a wider understanding of how dangerous the space shuttle is, and hopefully introduce some free market thinking.
This letter was run in its entirety in the November 1986 edition of Physics Today, the general interest magazine of the American Physical Society. One other technical journal ran it in highly abbreviated form.
As is typical in areas run by government, nothing has changed over the past seventeen years. Hopefully the second shuttle disaster will provide the impetus to ground the shuttle permanently and allow free market alternatives to flourish.
Physics Today, November 1986
To the Editor:
The recent tragic loss of the space shuttle Challenger has reopened many basic issues regarding our national space program. Many mildly enthusiastic supporters of the shuttle, and even some opponents, have been so moved by the loss as to advocate building a replacement shuttle to continue the original shuttle program. However, if we seek a suitable memorial to the brave individuals who perished in the shuttle accident, then we should learn from this disaster and not repeat previous mistakes.
The place to start is with the design of the shuttle itself. NASA has recently released film of the shuttle launch that indicates signs of trouble some 15 seconds before Challenger exploded. Most discussions of this issue have focused on the decision not to monitor more closely the performance of the solid-fuel boosters. This misses the essential point. Even if the shuttle crew had known at the instant of launch that the shuttle was going to explode in little more than a minute they would still have died. The Shuttle has no safety margin at launch. Either everything works right or the crew goes down with the ship.
The space shuttle is the first manned US space vehicle that has no provision for emergency escape during launch. The Mercury, Gemini, and Apollo programs all recognized the great dangers and uncertainties in any propulsion system capable of boosting man into space and made explicit provision for the type of accident that blew Challenger apart. The decision was made, early in the shuttle design, to remove these safety precautions to meet payload, crew size and mission length requirements. Given the nature of both solid- and liquid-fuel rockets, the laws of probability guarantee that something would eventually go wrong either at the launchpad or during the boost phase. And given the rather incredible design choices made, it was inevitable that astronauts would die in either of these cases.
It is possible to obtain a reasonable safety margin by returning to the equipment used in the first few shuttle launches. There the crew was limited to two astronauts to allow the installation of ejection mechanisms. Of course, this sacrifices one of the major goals of the shuttle, the ability to take payloads and mission specialists into orbit.
Unfortunately, there is another safety problem that has no easy remedy. The problems with the insulating tiles are well known, and the potential for disaster if a tile is lost over a critical area of the shuttle reentry is obvious. What is not so well known is that such a disaster has almost occurred. One shuttle on the reentry came within seconds of burning through a main wing support due to loss of tiles. The failure of this support would have caused the shuttle to crash, killing all on board.
Given the size of the shuttle, it is not feasible to return to the proven heat-resistant alloys used on previous manned space vehicles. Given the problems with keeping the tiles attached during launch and reentry, it is inevitable that despite NASA’s best efforts a critical tile will someday fall off and another shuttle crew will go up in flames with their shuttle.
If the shuttle were a reliable and economical way to get into space, then it might make sense to try to live with its inherently poor safety margins. Unfortunately the reliability and economic records of the shuttle are dismal. Its reliability is so questionable that even before the Challenger loss the Air Force was developing an expendable launch vehicle to supplement the balky shuttle. Another of the major goals of the shuttle was very rapid turnaround time. As for economics, the shuttle will never fly again without massive subsidies once again in stark contrast to the original NASA promise.
The nation’s space program has three alternatives. It can continue the shuttle program with whatever “quick fixes” are deemed necessary, it can develop alternatives to the shuttle, or it can leave the launch business altogether. Continuing with the shuttle means future disasters like the Challenger explosion. The price in precious lives and in replacement shuttles will be much too great. Letting NASA develop alternatives is equally unpalatable. The shuttle’s performance compared with NASA’s promises about its performance creates a very serious credibility problem for NASA. To entrust this group with the responsibility for finding a replacement for the shuttle is to risk another piece of aborted technology ruined by bureaucratic and political intrigue.
Getting NASA out of the space-launch business is not as naive a proposal as it might seem. There are many ways of getting into space. Expendable launch vehicles, air-breathing ramjets and sane shuttle designs are only three possible options. It is impossible to predict which method will prove the most reliable or economical. If we are to cut the expense of space travel dramatically, we must free the space-launch business from bureaucratic management and put it squarely into the innovative, cost-competitive environment of the free market. Launching payloads into space is a service that market forces can provide, just as they provide automobiles, computers, and clean laundry. There is no rational justification for US taxpayers to subsidize the expense of rocket development and rocket launches. Let those who directly benefit pay the bill, and let the rest of us spend our money on items we deem important.
Market forces are no panacea. Space exploration will continue to be the domain of brave, intelligent and courageous men and women who are willing to risk their lives pushing technology to its limits. There is no shortage of such people and there is also no shortage of space entrepreneurs willing to push our people and technology to their limits to create a reliable, cheap and safe space transportation system. All we need do is get government out of the way and let them do it. If we learn this lesson from the Challenger loss, then we will have created the most suitable memorial to the individuals who died on that flight.
John Bartel Tom Coughlin Charlestown, Massachusetts 2/86
February 4, 2003