TCS Daily

Apollo Creed

By Jeffrey Goldader - May 8, 2003 12:00 AM

Two paradigms that have become central features of the way NASA works are being challenged. The end result of those challenges will dictate the form, and possibly even the future existence, of the American human space flight program.

Once again, the search is on at NASA for a new spacecraft to help take the load off the space shuttle. Dubbed the "Orbital Space Plane," or OSP, this latest vehicle, whose design has yet to be chosen, is to take about half a dozen astronauts and a small amount of cargo to and from the International Space Station. Ideally, the OSP will be reusable, safe, affordable, and reliable. If the shuttle is a valid example, then NASA must choose the winning design carefully, for it may become the mainstay of the fleet for 25 years.

NASA itself describes the space shuttle as the most complex machine ever built. There is an inherent conflict between that description and the desired adjectives: safe, affordable, reliable. Of the original four orbiters, two have been lost, and more than $100 billion has been spent on the space shuttle system.

Since the space shuttle had wings and was reusable, the prevailing paradigm (intended or not) for new crewed spacecraft was that they also had to have wings and be reusable. Wings grant the advantage of greater maneuverability during re-entry than a capsule, easing the problem of reaching a suitable landing site. Reusable spacecraft were believed to offer lower life-cycle costs, since new ones did not have to be built every mission. But with wings and reusability also come complexity, the necessity of expensive technology development, and costly between-mission maintenance; and safety, affordability, and reliability become more difficult to achieve.

This is not purely a philosophical argument; the list of failed winged, reusable space launch vehicles seriously pursued by NASA since the 1980's includes at least three programs: the National Aerospace Plane (NASP), the X-33, and X-34. (The X-38, cancelled last year, is not included, since it was a down-only lifeboat for the International Space Station, not a launch vehicle.) The NASP and X-33 were utterly dependent on nonexistent technology in order to fly. The significant necessary advances in the difficult areas of propulsion and materials did not come. Over $1 billion was spent on the X-33 alone before it was cancelled, and somewhere around $200 million on the X-34, a vehicle capable of lofting small satellites into orbit (I was unable to find an estimate of NASP expenditures). The paradigm of winged, reusable vehicles has many problems, yet the very name of the Orbital Space Plane project shows the paradigm obviously lives on at NASA. But in the last few days, a surprising revelation shows there might be a challenge in the works.

On April 30, Keith Cowing's NASA Watch website published the results of a quick study commissioned by NASA. Four Apollo veterans - two high-ranking engineers and two astronauts who flew in both Apollo spacecraft and the space shuttle - were asked to determine if a vehicle derived from the cone-shaped Apollo command module (CM) could meet the goal of simply bringing crews down from the space station. The conclusion was that not only could the Apollo CM do the job, but with the addition of a propulsion module, it could meet most of the Orbital Space Plane's requirements.

Why Apollo? The Apollo command and service modules, the study report notes, were highly robust and fairly well understood. The CM in particular offered a simple system that had a perfect safety record bringing astronauts down to Earth. The heat shield was a tough resin designed to burn away during re-entry, not fragile tiles. A similar heat shield on the Russian Soyuz has had a perfect safety record since 1967. Returning from the Moon, Apollo CMs had re-entered the atmosphere at 50% greater speed than a re-entry from low Earth orbit. An enormous database still exists, as well as the knowledge of a great many active and retired Apollo program veterans.

That said, the study board noted that project would not be as simple as dusting off the plans and throwing metal together. Though the engineering drawings remain, modern production systems use CAD/CAM, not paper drawings. Every subsystem would have to be redesigned to use modern components. Yet the board noted that, as an example, a redesigned computer system might still use the Apollo algorithms. The result would be an Apollo-derived spacecraft, not a duplicate.

NASA has apparently considered and rejected such Apollo-type capsules many times before. But in the wake of the loss of the space shuttle Columbia, and estimated down-only capability for the space plane in 2010 (2012 for a flight up with crew) NASA has not only the opportunity, but perhaps the obligation, to search for simpler solutions that might be available sooner. The Apollo board noted that the CM-derived return vehicle might be available 4-6 years after the contract was signed, and a vehicle capable of sending crew to the station a year or two later. Little enough new technology development would be needed that the dates are probably much more secure than the space plane's schedule.

How will NASA greet this news? This reveals the second paradigm: the history of NASA shows it to be inherently a research and development organization, dedicated to exploring new places and new technologies. Yet at the same time, NASA is being asked to create not risky test vehicles, but operational vehicles, capable of safely, reliably, and affordably moving people to and from orbit. NASA must wrestle with the tension between developing new technology, and using proven technology. Apollo-derived capsules vs. winged, reusable spacecraft is an example of that tension. Does NASA have the institutional will and ability to forego entirely new technologies, in exchange for proven, conservative designs? And would that even be the right thing to do? Only time will tell. But the consequences of another failure are great, and the decision could well decide the future of American human space flight.

The author's views are his own and do not reflect the views of any organization with which he is affiliated.

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