Low-Density Supersonic Decelerator
![]() Artist's rendering of LDSD test vehicle in flight | |
Manufacturer | Jet Propulsion Laboratory |
---|---|
Country of origin | United States |
Operator | NASA |
Applications | Technology demonstrator |
Specifications | |
Spacecraft type | Hypercone |
Launch mass | 3,120 kg (6,878 lb)[1] |
Dimensions | Diameter: 4.7 m (15 ft 5 in)[1] |
Regime | Suborbital |
Production | |
Status | In production |
Built | 3 |
On order | 0 |
Launched | 2 |
First launch | June 28, 2014 |
The Low-Density Supersonic Decelerator or LDSD is a reentry vehicle designed to test techniques for atmospheric entry on Mars. The disc-shaped LDSD uses an inflatable structure called the Supersonic Inflatable Aerodynamic Decelerator (SIAD), which is essentially an donut-shaped balloon, to create atmospheric drag in order to decelerate the vehicle before deploying a large supersonic parachute.[2] The goal of the project is to develop a reentry system capable of landing 2- to 3-ton payloads on Mars, as opposed to the 1-ton limit of the currently used systems.[3]
The vehicle is being developed and tested by NASA's Jet Propulsion Laboratory.[1] Mark Adler is the project manager.[4]
The vehicle was tested in 2014 and 2015, and a third test is planned for 2016.[5]
June 2014 test flight
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The test flight took place on June 28, 2014, with the test vehicle launching from the United States Navy's Pacific Missile Range Facility on Kauaʻi, Hawaiʻi, at 18:45 UTC (08:45 local).[4] A high-altitude helium balloon, which when fully inflated has a volume of 975,000 cubic meters (34,430,000 cu ft),[1] lifted the vehicle to 36,500 meters (119,900 ft).[6] The vehicle detached at 21:05 UTC (11:05 local),[4] and four small, solid-fuel rocket motors spun up the vehicle to provide stability.[6]
A half second after spin-up, the vehicle's Star 48B solid-fuel motor ignited, powering the vehicle to Mach 4.32 and a peak altitude of 58,200 meters (190,900 ft).[6] Immediately after rocket burn-out, four more rocket motors despun the vehicle.[1] Upon slowing to Mach 4.08, the 6-meter (20 ft) tube-shaped Supersonic Inflatable Aerodynamic Decelerator (SIAD-R configuration) deployed.[6] SIAD is intended to increase atmospheric drag on the vehicle by increasing the surface area of its leading side, thus increasing the rate of deceleration.[7]
Upon slowing to Mach 2.54 (around 86 seconds after SIAD deployment[1]), the Supersonic Disksail (SSDS) parachute was deployed to slow the vehicle further.[6] This parachute measures 30.5 meters (100 ft) in diameter, twice the area of the one used for the Mars Science Laboratory mission.[8] However, it began tearing apart after deployment,[9] and the vehicle impacted the Pacific Ocean at 21:35 UTC (11:35 local) travelling 32 to 48 kilometers per hour (20 to 30 mph).[4][10] All hardware and data recorders were recovered.[7][10] Despite the parachute incident, the mission was declared a success; the primary goal was proving the flight worthiness of the test vehicle, while SIAD and SSDS were secondary experiments.[7]
2015 test flights
A second test flight of LDSD took place in June 2015, at the Pacific Missile Range Facility. This test focused on the 6-meter (20 ft) SIAD-R and Supersonic Ringsail (SSRS) technologies, incorporating lessons learned during the 2014 test.[11] Changes planned for the parachute included a rounder shape and structural reinforcement.[9] After several weather-related scrubs, the flight occurred on June 8.[12][13] As in the first test, the SIAD structure inflated successfully but the parachute was damaged during deployment.[14][3]
Gallery
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33.5-meter Supersonic Ring Sail Parachute
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6-meter SIAD-R
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8-meter SIAD-E
References
- 1 2 3 4 5 6 "Press Kit: Low-Density Supersonic Decelerator (LDSD)" (PDF). NASA.gov. May 2014. Retrieved August 12, 2014.
- ↑ Erdman, Shelby Lin; Botelho, Greg (June 29, 2014). "NASA tests flying saucer craft for future manned mission to Mars". CNN.com. Retrieved August 12, 2014.
- 1 2 Alan Boyle. "Oh, Chute! NASA's Flying Saucer Test Ends With Only Partial Success". NBC News. Retrieved June 9, 2015.
- 1 2 3 4 Carney, Emily (July 1, 2014). "NASA's Low-Density Supersonic Decelerator Test Flight Hailed as a Success". AmericaSpace. Retrieved August 12, 2014.
- ↑ Agle, D. C. (March 26, 2015). "Take a Spin With NASA Cutting-edge Mars Landing Technology". NASA. Retrieved March 28, 2015.
- 1 2 3 4 5 Parslow, Matthew (June 28, 2014). "LDSD passes primary technology test but suffers chute failure". NASA Spaceflight. Retrieved August 12, 2014.
- 1 2 3 McKinnon, Mika (June 29, 2014). "A Successful First Flight for of the Saucer Test Vehicle over Hawaii". io9.com. Retrieved August 12, 2014.
- ↑ Chang, Alicia (June 1, 2014). "NASA to test giant Mars parachute on Earth". Las Vegas Review-Journal. Associated Press. Retrieved August 12, 2014.
- 1 2 Boyle, Alan (August 8, 2014). "Flying Saucer Videos Reveal What Worked and What Didn't". NBC News. Retrieved August 12, 2014.
- 1 2 Rosen, Julia (June 30, 2014). "NASA Mars test a success. Now to master the parachute". Los Angeles Times. Retrieved August 12, 2014.
- ↑ "Press Kit: Low-Density Supersonic Decelerator (LDSD)" (PDF). NASA. June 2015. Retrieved August 27, 2015.
- ↑ Langfold, Christina (June 6, 2015). "NASA’s Flying Saucer Look-Alike Test Flight Delayed to Monday". Wall Street OTC. Retrieved June 6, 2015.
- ↑ "LDSD Powers Up for Drop". nasa.gov. Retrieved June 9, 2015.
- ↑ Allman, Tim (June 9, 2015). "Parachute on Nasa 'flying saucer' fails in test". BBC. Retrieved June 9, 2015.
External links
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