As the millions who watched video of NASA’s “Flying Saucer” test over Hawaii last June know, the so-called Low Density Supersonic Decelerator is a two-stage device. The first stage is a huge, durable, donut-shaped balloon that inflates around the entry vehicle, reducing its speed from March 3.5 or higher to Mach 2 or slower. The second is a 30.5-meter-diameter parachute that further slows the vehicle to subsonic speeds. NASA will need this kind of capability if it ever wants to land payloads much heavier than the Curiosity rover on Mars.
Preparing the giant parachute for its trip to the stratosphere was a lot of fun, as this video indicates. It was far too large to be tested in a wind tunnel, so Jet Propulsion Laboratory engineers were forced to get creative, using the four-mile test track at the Naval Air Weapons Station at China Lake, California, in the Mojave Desert, to mount a sled powered by solid booster rockets. The parachute was dropped from a Knighthawk helicopter from a height of 4,000 feet, after which it fell until it latched onto the sled. Then it got pulled (with 100,000 pounds of pull thrust, to approximate a supersonic trip through the thin Martian atmosphere) for the ride of its life.
The video rewards repeated viewings. We don’t know who chose Metallica’s “Enter Sandman” for the score, but we’re not necessarily opposed to it.