Illustration of an Apollo spacecraft approaching the docking adaptor used for ASTP. Will a direct descendant of Apollo perform similar docking with the International Space Station? (credit: NASA)

Orbital Space Plane: Back to Apollo?

by Jeff Foust
Monday, May 5, 2003

When NASA first announced plans to develop the Orbital Space Plane (OSP) last year, most people assumed it would be exactly that: a winged, reusable vehicle—in essence a mini-shuttle—that could serve as both a crew return vehicle (CRV) and crew transfer vehicle (CTV) for the International Space Station. Many of the vehicle designs presented to the public by companies like Boeing and Orbital Sciences Corporation in recent months have indeed been either winged or lifting body vehicles, direct descendants of recent experimental designs like the X-37 or older concepts like the HL-20 and X-24.

Thus, it was something of a surprise when NASA released its initial Level One requirements for the OSP in February. Those requirements stated that the vehicle must be capable of carrying four people as well as transfer injured crew members to “definitive” medical care on Earth within 24 hours. The vehicle had to be able to act as a CRV by 2010 and a CTV, launched on an expendable vehicle, by 2012. The vehicle also had to be cheaper, safer, and more maneuverable than the Space Shuttle.

What was most notable about the Level One requirements was not what they included, but what they omitted. Nowhere did the document specify a winged vehicle, nor did it even directly require the vehicle to be reusable. This showed that NASA seemed willing to at least consider the possibility of using simple capsules—which many believe could be cheaper to develop and operate than winged vehicles—as a CRV and CTV. Indeed, one of the four notional designs presented by NASA when it announced the Level One requirements was a capsule, sitting alongside winged and lifting body concepts.

Most had assumed that any capsule developed for OSP would be of a brand-new design, with little resemblance and heritage from previous US or Russian designs. However, a study back in March by a small team of Apollo-era managers and astronauts has suggested an alternative approach: basing a capsule CRV/CTV design on the Apollo Command Module (CM). The study, which has made its way to the public in the last week, examines how much the design of a spacecraft retired nearly three decades ago can be used to influence the development of a new spacecraft that is still nearly a decade in the future.

The Space Review obtained a copy of the report, titled “Report on Top-Level Assessment of Use of Apollo Systems for ISS CRV”, last week. The appearance of the report made it clear it was making the rounds of the space community: skewed pages, slightly blurred text, and the presence of indicia from two different fax machines on the top of the pages. It all made it look like the report was being passed along unofficially, as if through some electronic samizdat press. (Fortunately, an easily-readable online version of the report is now available on SpaceRef.com.) The report, dated March 17, is based on meetings held on March 13 and 14 by a five-person team with an impressive pedigree: former astronauts Vance Brand and John Young, who between them have ten space flights, including three Apollo missions; former Johnson Space Center director Aaron Cohen; former Dryden Flight Research Center director Ken Szalai; and former NASA deputy administrator Dale Myers. All have direct experience with Apollo as astronauts, engineers, or managers.

The title of the report, at first glance, suggests something both fascinating and fantastic. It leaves one with the mental picture of engineers raiding museums, scavenging components from old Apollo CMs for use on a new vehicle. (The report quickly puts this concept to rest by concluding that existing Apollo hardware would be unsuitable because of “obsolescence, lack of traceability, and inability to qualify these components for flight.”) The report concluded that an Apollo-derived CRV/CTV “has sufficient merit to warrant a serious detailed study of the performance, cost, and schedule for this approach.” However, on closer reading, the report reveals that precious little from Apollo would be directly relevant to an OSP.

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