Retro Rocketeers
If a capsule was good enough to get a crew to the moon, these old-timers say, it's good enough to get a crew back to Earth.
- By James Oberg
- Air & Space magazine, May 2004
Lockheed Martin has considered both lifting bodies and ballistic capsules for the proposed Crew Exploration Vehicle. The rounded capsule is shown attached to a service module, which provides propulsion.
Lockheed Martin
(Page 3 of 4)
To keep the stretched Apollo capsule from getting too heavy, the group counted on 40 years of progress in lightweight composite materials. And even though upgrading to a station-compatible cabin air pressure of 15 pounds per square inch, three times Apollo’s pressure, would add weight, that wasn’t considered to be an insurmountable problem.
This was only the basic vessel, though. Inside the roomier command module, practically nothing would remain the same. “Virtually every system would have to be redesigned, even if it were decided to be replicated,” the group concluded in its report. “Entirely new electronics systems and displays will be required.”
Szalai recalls wondering, “Could you use any of the [old] hardware? We spent a few hours, system by system. None of it was supportable; vendors were long out of business. Could we even use the seat? No, we knew how to build better ones now.” One item did survive, though. The Apollo hand controller, used for pilot inputs, could “probably be replicated,” the report stated, although the software that ran it would have to be rewritten from scratch.
“By the end of the first day,” Szalai recalls, “we knew where we were going.” The team disbanded for the evening, some heading to the homes of relatives, some to dinner (and further discussions) at their hotel. The next morning, they turned to Apollo’s landing method, the classic splashdown. Here the group departed from tradition: They agreed that there is an advantage in coming down on dry land: After all, the Russians had been doing this for years with Soyuz capsules (see “Aiming for Arkalyk,” Aug./Sept. 1998). Dry landings would eliminate the expense of rescue ships but would require the engineering of new descent hardware.
Myers, briefing the House subcommittee on space a few months later, called the dry-land landing system “the only major new technology, other than long-duration storage in space,” needed to convert an Apollo command module to a lifeboat. The requirement to make an emergency return anywhere on Earth within 24 hours would add expense and complication, since NASA would need a large number of landing sites to be on standby. But if a service module were attached to provide steering and propulsion, the number of sites would drop dramatically.
Testifying before that same panel, Michael Griffin, a former NASA chief engineer, dismissed worries about landing accuracy. Now with In-Q-Tel of Arlington, Virginia, Griffin told the panel: “Most of the Apollo landing dispersions would have fit easily within the boundaries of Dulles Airport. It is not necessary to do better than that.”
Szalai’s group then turned to the subject of heat protection. The ablative material used on the Apollo heat shield—a phenolic epoxy resin—is no longer manufactured. Fortunately, better materials have come along since, some of which have even been flight-qualified. In fact, the heat shield for an Apollo-derived crew rescue vehicle would have a key advantage over the original: It could be a clip-on, discarded after the fiery return to Earth. And that, said Griffin, made the Apollo-derived rescue vehicle “a system with only one non-reusable component that…can be, almost literally, dirt cheap.”
If the Apollo command module appeared to be a perfectly good lifeboat, all the same advantages applied to the crew transfer, or “up” vehicle. The capsule could easily be perched on an expendable rocket, like a Delta or Atlas, for delivery to orbit. If NASA wanted to return to the moon, a wingless capsule looked even more appealing. Griffin told Congress that a semi-ballistic capsule like Apollo’s would be “much better adapted [than winged vehicles] to any requirements to go beyond low Earth orbit.”
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