CAPE CANAVERAL, Fla., Feb. 18 (UPI) -- NASA issued requirements Tuesday for a new spaceship that will be safer than the shuttle and Russia's Soyuz capsules, big enough to hold at least four astronauts, and available to serve as an emergency escape vessel for International Space Station crews by 2010.
"It's reached the point where we need an alternative system to the space station," said Dennis Smith, manager of the new Orbital Space Plane program at NASA's Marshall Space Flight Center in Huntsville, Ala.
Outlined by NASA last year, the space plane has taken on added impetus with the grounding of the space shuttle fleet in the wake of the Columbia accident. Seven astronauts died Feb. 1 when the shuttle broke up over Texas as it glided toward a landing strip in Florida to conclude a 16-day research mission. An investigation into what caused the accident is under way.
The accident leaves Russia in charge of re-supply and crew rotation missions to the ISS, where two NASA astronauts and one Russian cosmonaut currently live. NASA's over-arching goal in the space plane program is to supplement the Russian Soyuz capsules that now serve as the station lifeboats with a U.S. vessel capable of ferrying at least four crew members home in case of a medical or other emergency. NASA wants the space plane, which will be launched on an expendable rocket, available by 2010 or sooner.
"(After the accident), we looked if we could do it faster, but the plan we have in place already is a year faster than what shuttle development took," Smith said.
Compared to the shuttle, NASA wants the new ship to be less time-consuming to prepare for launch, better able to meet its launch dates, and have more ability to maneuver in orbit. In addition, returning astronauts should be able to fly in the space plane without pressurized flight suits, program requirements released Tuesday show.
By 2012, NASA wants the space plane, or a future variant of it, available to launch crews to the space station as well.
With regard to safety the document said: "The risk of loss of crew shall be, with high confidence, lower than the space shuttle for the transport mission," and "lower than the Soyuz for the rescue mission."
In addition, NASA wants the system designed for minimum life-cycle costs, available for use through at least 2020, able to stay in orbit for four to six months at a time, and able to carry cargo to and from the space station to support "a minimal level of science."
NASA tried for years to develop a new reusable spaceship like the shuttle, but found the technological hurdles too great to overcome. Last year, the old program was split into two: an advanced technologies research and development effort and the Orbital Space Plane, which will more closely resemble the Russian Soyuz and U.S. Mercury, Gemini and Apollo spaceships, than the reusable space shuttles.
"A fully reusable singe-stage-to-orbit shuttle only makes sense if you're flying its several times a week," said John Pike, a space program analyst with GlobalSecurity.org. "The largely reusable shuttle makes sense if you're flying it several times a month, but if you're flying just several times a year, you basically want to throw away the booster and just reuse the expensive electronics and life support systems."
Concurrent with the space plane effort are two related programs to design, build and test an automated rendezvous and docking system and an on-pad escape system that would jettison a crew's capsule to safety in case of an accident at launch.
"Safety will be a key focus," Smith said.
