NASA reveals early results of LDSD “flying saucer” test flight
NASA’s Low-Density Supersonic Decelerator (LDSD) “flying saucer” test vehicle successfully reached near-space in late June, allowing them to test certain Martian landing conditions, and NASA held a video-rich briefing about it today, August 8.
“A lot of the focus of the agency […] is developing technologies to facilitate human exploration of Mars,” said Jeff Sheehy, senior technologist with the Space Technology Mission Directorate, during the briefing. “You gotta get there, you gotta land there, you gotta live there, and you probably wanna return from there. So these technologies that [Mark Adler, project manager of the LDSD at NASA’s Jet Propulsion Laboratory (JPL)] and [Ian Clark, principal investigator of the LDSD project at JPL] have been working on are all about landing on Mars. Landing on Mars is really hard,” he said.
It is a balloon-launched vehicle, meaning that a balloon with a volume of 34 million cubic feet carried the 7,000 pound payload to an altitude of 120,000 feet at about 1,100 to 1,200 feet per minute. The balloon expands as it gets higher, and when the saucer reached target altitude, the balloon dropped the LDSD vehicle.
After that, the vehicle’s two spin motors fired, bringing it to a spin of about 50 rpm, and then the Star 48 solid rocket motor fired for about 71 seconds to accelerate the vehicle to Mach 4.3. “Then we fire the spin-down motors, the thing comes to a dead stop, and then flies very stably at Mach 4. So we’re very happy about this,” Adler said. “At this point, we’ve actually achieved most of the objectives of the flight that we had this summer.”
The main objective was to show that they could get the vehicle to the correct altitude and airspeed to properly test new technologies for future missions to Mars. It was necessary to bring the vehicle to about 180,000 feet where the atmosphere has about the same density as the Martian atmosphere, and to ensure it could fly successfully at Mach 4.
“We’ve been developing a number of technologies as part of this project, technologies that will enable us to land payloads significantly larger than the Curiosity rover, land on the places on Mars that we’ve never been able to get to before, and land them more accurately,” Clark said.
Two such technologies were carried on the flight and will be tested further next year on the same type of test vehicle. One, the Supersonic Inflatable Aerodynamic Decelerator (SIAD) is a large air brake wrapped around the diameter of the saucer-shaped vehicle that deployed during the flight.
The second is a supersonic ballute and the Supersonic Disk Sail Parachute it was designed to help deploy. With more than double the area of the parachute used for the Curiosity mission, this is the largest supersonic parachute ever flown. During the test flight, when the parachute deployed, it quickly began to tear apart.
“We’ve learned a lot from this video already,” Clark said. “For one, that we have more to learn about supersonic parachute inflation.”
Two more flight tests are planned for the project.
LDSD is part of NASA’s Space Technology Mission Directorate, which, according to NASA, “is innovating, developing, testing and flying hardware for use on future NASA missions. Over the next 18 months, the directorate will make significant new investments to address several high-priority challenges in achieving safe and affordable deep space exploration.”
Check out footage from the test here:
Rae Botsford End is a freelance writer and editor whose primary work currently is writing technical white papers, contributing to SFI, and working on a speculative fiction novel that she hopes to have published soon. Rae wanted an opportunity to report on the various space-related events in and around Florida's Space Coast and approached SFI's founder about the possibility. Rae now covers an array of subjects for our growing website.