Test flight of NASA's Low Density Supersonic Decelerator experiment may increase the mass of payloads deliverable to the Martian surface.
NASA has prepared its high altitude Low Density Supersonic Decelerator experiment for another round of Pacific launch attempts starting this weekend and extending into early July after unseasonable wind conditions thwarted a much anticipated test flight earlier this month of technologies with the potential to deliver human scale payloads to the Martian surface.
The U. S. Navy’s Pacific Missile Range Facility in Kauai has cleared launch attempts for June 28, 29 and 30, July 1 and 3.
Timeline for NASA's Low Density Supersonic Decelerator experient. NASA
The test begins with a balloon launch from Kauai that will carry the 6,900 pound saucer shaped LDSD payload to an altitude of 120,000 feet. Once released from the balloon, the Supersonic Inflatable Aerodynamic Decelerator would be powered to 180,000 feet and a Mach 4 velocity with a solid rocket motor.
At those altitudes, the Earth’s atmosphere is thin and suitably Martian-like for the test of what is essentially an inflatable heat shield.
The 15 ½ foot wide SIAD saucer is designed to inflate to 20 feet and begin to slow with atmospheric drag. After braking to Mach 2.5 –- about three minutes after the balloon release -- a 100 foot wide supersonic parachute deploys to lower the SIAD payload to the ocean surface.
The first test flight window included a half-dozen launch opportunities between June 3-14. In each case, high altitude winds were not blowing away from the island to assure the safety of the inhabitants from the descending flight hardware.
NASA's Space Technology Mission Directorate is overseeing the development, which drew its inspiration for the rapid inflation of the SIAD from the Hawaiian pufferfish.
Pufferfish, an inspiration for LDSD. Chris Laughlin
The sea creatures are poor swimmers and susceptible to hungry predators. They become quickly inedible by ingesting huge amount of water and swelling to several times their normal size.
Currently, NASA relies on technologies that date to the successful Mars Viking lander missions of the 1970s to reach the surface of the red planet. The Curiosity rover, which weighs in at about a ton, was right at the limit of what the current technology supports as it settled to the bottom of Gale Crater with the help of NASA’s sky crane in August 2012.
A human mission of the type NASA envisions for the 2030s would require a 40 ton capability.