The long-awaited flying saucer test finally happened in the Hawaiian skies this weekend. The primary mission of evaluating the test vehicle was a complete success, but the bonus missions of evaluating new landing technologies were more mixed, with the parachute failing to deploy.
The saucer-shaped test vehicle being lifted aboard the Kahana recovery vessel after the first free-flight of the Low-Density Supersonic Decelerator.
The Low-Density Supersonic Decelerator (LDSD) project has three planned test flights: the one this weekend was designed to test the launch vehicle itself, while the next two flights are designed to evaluate prototype landing technologies for future Mars missions. That means that the primary mission for the first test flight this weekend was really straightforward: to prove that the saucer-shaped test vehicle can actually fly, a key preliminary step in using it to test out new technologies for Mars landings. If it also served as a test for the landing technologies, that's a research-bonus.
The thin atmosphere on Mars makes landing delicate equipment carefully challenging. The two new technologies being developed in the LDSD project are an inflatable disc, Supersonic Inflatable Aerodynamic Decelerator (SIAD), that increases drag on the vehicle, and an enormous parachute, Supersonic Disk Sail Parachute (SDSP). If they work, they'll open up the possibility for bigger and bigger equipment on Mars, raising the maximum payload weight limit to over two tons! In order to test this equipment on Earth, the tests need to take place in the upper stratosphere, where the air is thinner.
The LDSD is at the upper-left, at the tip of the contrail, while the balloon that provided initial lift is to the mid-right.
Here's how the day worked out:
A balloon launched at 8:45 am local time on Saturday, carrying the test vehicle to about 36,600 meters (120,000 feet) over the Pacific Ocean. At 11:05 am, the balloon dropped the test vehicle, at which point the saucer fired its rockets, initiating powered flight to boost it to an even higher altitude. Once the vehicle reached the upper stratosphere at 54,900 meters (180,000 feet), the rockets cut out, and the bonus mission of testing the landing prototypes began.
Two members of the recovery crew swim towards the test vehicle, with recovery vessel Mana'o II in the background.
The disc worked great, inflating and increasing drag for the plummeting test vehicle, but the parachute failed to (fully) deploy. The saucer smacked into the Pacific Ocean at 11:35 pm. The inflatable disc didn't just slow the vehicle during its decent; it also acted a bit like a child's water-wings and kept the vehicle afloat while crew recovered the saucer. They even managed to clamber aboard, very briefly using the aircraft as a boat. All the test hardware and the black box data recorder were recovered without difficulty.
Speaking at a press conference after the test, project manager Mark Adler is delighted by the primary mission's total success, and the mixed success of the bonus missions:
"We are thrilled about yesterday's test. 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."
If you're wondering why he's so unreservedly giddy about the test flight when the parachute failed to deploy, that's because the planned parachute test is nearly a year away. It is only because the test vehicle performed perfectly, and SAID inflated perfectly, that we even had a chance to check out the parachute's performance this early in the testing sequence!
The flying saucer resting after its first flight aboard recovery vessel Kahana.
Read more at the LDSD project page. Images credit NASA/JPL-Caltech