NASA tests flying saucer designed to land heavier payloads on Mars
By Anthony Wood
July 1, 2014
NASA has successfully carried out the first of three airborne tests for its Low-Density Supersonic Decelerator (LDSD), a saucer shaped test vehicle which will one day be used to slow down scientific payloads entering the atmosphere of Mars. This new system of atmospheric deceleration will allow the agency to contemplate heavier, more ambitious endeavors, building towards a manned mission to the red planet.
The proving mission was designed to test two elements of the LDSD, the Supersonic Inflatable Aerodynamic Decelerator (SIAD), and the supersonic parachute. The SIAD is in effect a large, tightly packed inflatable doughnut that surrounds the rim of the saucer-shaped test vehicle. Once deployed the SIAD will increase the surface area of the spacecraft, thus creating extra velocity-killing drag as it interacts with the Martian atmosphere.
The second part of the test focused on the Decelerator’s supersonic parachute. This technology has been in use since 1976, when the agency used the system to successfully deploy two Viking landers onto the Martian surface. Updates to the system for the LDSD project have mostly centered around scale, with the supersonic parachute deployed in the skies over Hawaii being by far the largest specimen ever tested. It measures 110 ft (34 m) in diameter, twice the size of the parachute used to land the Curiosity rover in 2012.
On June 28, the LDSD began its ascent tethered to a vast balloon which would lift it 120,000 ft (36,576 m) above the Earth's surface. At this stage the test vehicle detached from the balloon, firing its rocket to push it a further 60,000 ft (18,288 m) higher in order to reach its operational height of 180,000 ft (54,864 m).
The mood in the control center at the US Navy's Pacific Missile Range Facility in Kauai, Hawaii was initially jubilant, with the SIAD inflating flawlessly around the saucer-shaped hull. However, the feeling of celebration quickly soured. Soon after deployment it became clear that the supersonic parachute had failed to fully open, instead finding itself dragged limply in the wake of the LDSD.
Despite this lack of parachute deployment, the data collected from the flight itself was to remain unharmed, stored as it was in the NASA equivalent of a black box. Upon splash down this black box separated from the LDSD, allowing search and recovery ships to locate it thanks to its integrated GPS system, and retrieve the test data for further analysis.
In a press conference later that day, NASA representatives stated that the test had been far from a failure, and had in fact been a complete success.
"We are thrilled about yesterday's test," stated Mark Adler, project manager for the LDSD at NASA's Jet Propulsion Laboratory, Pasadena, California. Adler continued, "The test vehicle worked beautifully, and we met all of our flight objectives. We have recovered all the vehicle hardware and data recorders and will be able to apply all of the lessons learned from this information to our future flights."