A key system for the first manned Orion deep space mission has been cleared for flight after NASA completed the final tests of the crew capsule parachutes on Wednesday. At the US Army Yuma Proving Grounds in Arizona, the last of of eight tests were completed using a dummy Orion capsule as the space agency put the parachute system through a series drops that included both normal and emergency flight conditions.
As the old saying goes, what goes up must come down, and when the first manned Orion mission returns to Earth it will be coming down at speeds not encountered by astronauts since the days of the Apollo Moon landings. When it re-enters the Earth's atmosphere, the crew capsule will be traveling at hypersonic speeds of 6.8 miles per second (11 km per second), or 32 times the speed of sound.
Atmospheric drag will eat up most of this velocity, but it will still be traveling at 300 mph (483 km/h) as it slows to subsonic speed. This has to be reduced further to 20 mph (32 km/h) if the spacecraft and crew want to avoid being smashed to pieces on impact. This is the job of the parachute system. Similar to that first developed for the Apollo Command Module, Orion's landing system consists of 11 parachutes covering an area of up to 36,000 ft² (3,300 m²). These are deployed in sequence using mortars, pyrotechnic bolt cutters, and 30 mi (48 km) of Kevlar cords over the capsule's roughly 10-minute descent through the Earth's atmosphere, slowing it down before it splashes down in the Pacific Ocean.
According to NASA, this midair maneuver has to go off perfectly even in the face of mishaps like a mortar failure of a parachute tearing, which is why the space agency has been dropping a mock Orion capsule out of the back of a C-17 transport plane over the Arizona desert from a height of over 6.5 mi (10.5 km).
These tests will not only benefit the next Orion mission, but will also be used to speed up the development of crew capsules by SpaceX and Boeing. NASA says that the data from the flight tests will be used to produce computer models and will reduce the number of live tests needed for the commercial manned spacecraft that will shuttle crews back and forth from the International Space Station.
"We're working incredibly hard not only to make sure Orion's ready to take our astronauts farther than we've been before, but to make sure they come home safely," says Orion Program Manager Mark Kirasich. "The parachute system is complex, and evaluating the parachutes repeatedly through our test series gives us confidence that we'll be ready for any kind of landing day situation."
Source: NASA
