In what will be the first of four high-altitude balloon flights tobegin in the summer of 2013, technologists at NASA's Jet PropulsionLaboratory (JPL) in Pasadena, Calif., and Wallops Flight Facilityin Wallops Island, Va., are preparing to test new decelerationdevices that could replace current descent technologies for landingever-larger payloads at higher elevations on Mars. NASA hasn't tested deceleration technologies supersonically since1972 when it conducted four high-altitude tests of a supersonicparachute used during the Viking program. "We've been stuckwith that design ever since," said Mark Adler, NASA'sLow-Density Supersonic Decelerator (LDSD) program lead. NASA willuse the same technology again this year when it delivers theCuriosity rover to Mars.
However, planetary landers of tomorrow will require much largerdrag devices than any now in use. "What we need is newtechnology to slow larger, heavier landers from the supersonicspeeds of atmospheric entry to subsonic ground-approachspeeds," Adler said. The LDSD program is aimed at giving NASA a new and improvedcapability. Funded by NASA's Space Technology Program, the JPL-ledteam plans to conduct full-scale, stratospheric tests of threepotentially breakthrough technologies. The aim is to raise theirtechnology-readiness levels to about six, which means they could beused in a flight project, perhaps as early as 2018.
The first two are supersonic inflatable decelerators, largepressure vessels that inflate around an entry vehicle and slow itfrom Mach 3.5 or faster to about Mach 2. One of these inflatabledevices measures nearly 20 feet in diameter (six meters), the othernearly 26 feet (eight meters). The third technology is a 110-foot(33.5-meter) parachute to further slow the entry vehicle from Mach2 to subsonic speeds needed for a safe landing. All three would bethe largest devices of their kind ever flown at speeds severaltimes greater than the speed of sound. The design calls for the team to attach a test vehicle equippedwith the decelerator and parachute to a Wallops-providedhigh-altitude balloon.
Once the balloon reaches an altitude ofabout 22 miles (36 kilometers) above Earth's surface, the rocketwould fire its engines and carry the test vehicle to Martianatmospheric densities at an altitude of 31 miles (50 kilometers) atMach 4. There, the test vehicle would deploy the supersonicdecelerator, followed by the parachute. Perfect Marriage of Capabilities The project leverages the strengths of both organizations, saidScott Schaire, Wallops LDSD acting project manager. While NASA JPLand its contractors are developing the test vehicle, decelerators,and parachute, NASA Wallops is responsible for balloon operations,balloon instrumentation, and other operations associated withballoon launches. One significant NASA Wallops-provided technology is an entirely newballoon launch system -- an effort Schaire's team undertookspecifically for the supersonic tests.
With this new system, thetest vehicle will be suspended from a vertical, 80-foot tower. Itsjob is preventing the test vehicle from hitting the ground as theballoon begins to lift off. A modified apparatus that resembles afarm-irrigation system will help technicians lay out the balloonand a new spool vehicle will hold the balloon until launch. In the first test as early as August 2013, the team plans toevaluate the performance of both the decelerator and parachute."Launching small rockets from large balloons," Schairesaid.
"What could be a better project for Wallops?". I am a professional writer from Bag & Luggage Agents, which contains a great deal of information about hair pieces bun , printed ribbons wholesale, welcome to visit!
Related Articles -
hair pieces bun, printed ribbons wholesale,
|
