A wingless space lifeboat designed to bring astronauts home from the planned International Space Station takes its maiden free flight Monday, gliding in after being dropped 23,000 feet above the Mojave Desert.
NASA’s X-38 aircraft is a so-called “lifting body,” built to glide through the sky on lift generated by its aerodynamic shape before deploying a huge controllable parachute. The aircraft has no landing gear; it sets down on skids.
The craft is the prototype for a “crew return vehicle” that the space agency is developing for the space station. Planners envision a six-person craft attached to the outside of the station, ready to carry crew members home if there’s an emergency and a space shuttle can’t be launched in time.
The white-over-black X-38 looks something like a patent leather shoe with a spat - but with tail fins that would look good on a Cadillac from the 1950s.
The aircraft has flown before, but never on its own. The previous flights have been attached to a pylon under a B-52’s wing.
In the new test, the unmanned craft will be carried aloft beneath the wing of a plane and released at 23,000 feet. It will make an unpowered descent, slung beneath a steerable parachute called a parafoil.
When deployed, the parafoil has an area of 5,500 square feet - as much surface area as the wings of a Boeing 747.
“Right now we’re just trying to get it down on the range,” said Bob Baron, the X-38 project director at NASA’s Dryden Flight Research Center.
Two small parachutes will precede the main chute, which will deploy around 15,000 feet. Landing is expected to be fully automated, but ground controllers will be able to take over if a problem arises.
Touchdown will be on a bombing range because Edwards’ famous dry lake beds are wet from storm runoff. And strong winds postponed the test rom Saturday until Monday morning.
Like the first space shuttle Enterprise, the X-38 is a prototype for use in the atmosphere and will never go into space. The Enterprise was lofted off the back of a jumbo jet to test the unpowered landing technique used by shuttles.
The X-38’s lineage goes back to the lifting-body aeronautical experiments of the 1960s and ‘70s when the Air Force and the National Aeronautics and Space Administration employed a fleet of wingless little craft.
The plywood-shell M2-F1 led the way, initially towed into the air by a Pontiac convertible speeding across Rogers Dry Lake, and earning the nickname “Flying Bathtub.”
The tests demonstrated that spacecraft could return to Earth as gliders, with the aerodynamic shape of the vehicle providing the lift that normal aircraft get from wings.
“We just took on the old knowledge that we had, all the data we had, and said this would not be a bad shape for something like a crew return vehicle,” Baron said.
A more advanced version of the X-38 will make a descent from space in 2000 and an operational Crew Return Vehicle must be ready by 2003, Baron said.
From space, the crew return vehicle - traveling backward - will fire a rocket engine to slow its speed and begin the fall from orbit. The rocket will be jettisoned and the craft will rotate to bring its nose forward for the fiery plunge into the atmosphere. The parafoil will begin to deploy around 50,000 feet.
The craft could evolve into a form that can also be used for ascents, Baron said.