NASA launches flying saucer for test flight to Mars
Xinhua, June 9, 2015 Adjust font size:
After nearly a week of weather-related delays, NASA launched its rocket-powered "flying saucer" on Monday to test the technologies that could someday help get heavy payloads to Mars, but the saucer's parachute deployed only partially.
The saucer-shaped low-density supersonic decelerator, or LDSD, was lifted off by a massive helium balloon from the U.S. Pacific Missile Range Facility in Kauai, Hawaii, at 7:45 a.m. local time (1745 GMT).
The flying saucer is equipped with a doughnut-shaped device called the supersonic inflatable aerodynamic decelerator (SIAD) and a super-strong parachute, both designed to slow down a spacecraft as it descend through the Martian atmosphere.
The helium balloon, roughly the size of three football fields, has taken about three hours to reach its float altitude of 120,000 feet (36,576 meters). About 45 minutes after the balloon reached test altitude, the saucer-shaped LDSD test vehicle was dropped.
A fraction of a second after dropping from the balloon, and a few feet below it, four small rocket motors fired to spin up and gyroscopically stabilize the saucer. Just over two seconds later, a Star 48B long-nozzle, solid-fueled rocket engine kicked in with 17,500 pounds of thrust, sending the test vehicle to the edge of the stratosphere, or about 180,000 feet (54,864 meters), at a speed of Mach 4, or four times the speed of sound.
At about Mach 3.8, the test vehicle deployed the supersonic inflatable aerodynamic decelerator. The 6-meter-wide SIAD decelerates the vehicle to approximately Mach 2.4.
Then the 33-meter-wide supersonic test parachute was supposed to unfurl to slow the descent even more. But the chute didn't open fully as planned. The stress of the supersonic air flow ripped the fabric apart. Without a workable chute, the low-density supersonic decelerator headed for a hard splashdown in the Pacific Ocean.
The flying saucer had its first field test on June 28, 2014. The inflatable decelerator worked as expected, but as soon as the parachute opened, it was shredded apart. The test was deemed a success by engineers, despite the vehicle's huge parachute apparently failing to deploy properly, according to local media.
The LDSD project, led by the Jet Propulsion Laboratory and sponsored by NASA's Space Technology Mission Directorate, involves two breakthrough technologies: a SIAD and an innovative new parachute. These devices may help scientists deliver double the current amount of payload, 1.5 metric tons, to the surface of Mars.
They also will greatly increase the accessible surface area that can be explored, and will improve the landing accuracy from a margin of approximately 10.5 km to a little more than 1.6 km. All these factors will dramatically increase the success of future missions to Mars. Endi