A new player has entered the business of delivering people and cargo to the International Space Station, using technology that harkens back to the space shuttle era. NASA awarded a contract this week to develop Dream Chaser, a spacecraft that will land on runways.
Since retiring the space shuttles in 2011, NASA has been in the embarrassing position of having no way to launch its astronauts into space, other than paying for rides on Russian Soyuz craft.
Considering the tensions between the U.S. and Russia over the conflict in Syria, the Americans would like to bring space flight back onto American soil as soon as possible.
To that end, NASA has handed over the task of delivering cargo and people to the International Space Station to the private sector, which can do it cheaper and more efficiently than government programs. Up to now it has worked with two private firms, but adding a third player — Sierra Nevada Corp. with its Dream Chaser — increases reliability and also keeps costs low through competition.
The most successful private space company so far has been Space-X, which has already sent its unmanned Dragon capsules to the station six times, made a successful return to launch pad with its re-useable Falcon 9 booster, and is developing a manned version of its Dragon capsule.
The other private contractor is Boeing, which is developing the Orion Crew capsule, designed for deep space missions, and has, so far, made one unmanned test flight.
A SpaceX Falcon 9 rocket lifts off on April 14, 2015.
Both of these designs return to Earth under parachutes and splash down in the ocean, an old technique used by the earliest space missions half a century ago.
The new player, Sierra Nevada Corp., has been invited to join the competition with a reusable, winged spacecraft that looks like a scaled-down version of a space shuttle. The lifting-body design was taken from an emergency escape vehicle that was originally designed for the space station, but was dropped because of budget restraints.
Lifting bodies use the entire vehicle as a wing, so they can be smaller and lighter than conventional aircraft. The concept goes back to the 1950s, when several prototypes were flown but never put into production. In fact, the opening sequence of the '60s television series Six Million Dollar Man showed the actual crash of one of these prototypes.
Dream Chaser is designed to sit on top of a regular rocket booster, the same technology currently used to launch satellites. The big difference is how it returns to Earth.
Instead of a wet landing in the ocean or thumping down onto land under parachutes, Dream Chaser will glide back from space and gently land on a runway — the way space shuttles used to do. It's small enough that it could land at any major airport, but will most likely land back at the Kennedy Space Center on a runway designed for shuttles.
A smooth runway landing is much easier on the crew and cargo than a sudden splashdown in the ocean, followed by nauseating rocking and rolling until you are hauled out by helicopter. It is also easier on sensitive scientific experiments that are returned from space to be examined by scientists on the ground.
NASA is covering its bases by adding a third contractor, which is exactly the way it should be. Space flight is in a transition from the hugely bureaucratic, over-budget government contracts of the past, to private companies that must deliver a product efficiently or be forced out of business. Competition keeps the costs down and will make space flight more widely available.
This is the same type of transition that brought airplanes out of the hands of the military and enabled the growth of the airline industry.
With space flight in the hands of the private sector, there is a better chance the rest of us normal folks can finally get up there.
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