Landing on Mars is hard. Gravity barely a third that of Earth's helps, but without oceans to splash down in or much in the way of an atmosphere to slow a spacecraft things get tough. As a result, engineers have spent a lot of time trying to come up with designs that will allow missions to touch down gently.
The best way to test these is to take the vehicles to heights where the atmosphere is as thin as that on the red planet. Footage from the latest effort is pretty awesome.
While the parachute's performance was disappointing, the results for the craft itself were more encouraging. "Our test vehicle performed as advertised," said NASA's Ian Clark. "The SIAD [Supersoinic Inflatable Aerodynamic Decelerators] and ballute, which extracted the parachute, also performed beyond expectations. We also got significant insight into the fundamental physics of parachute inflation. We are literally rewriting the books on high-speed parachute operations, and we are doing it a year ahead of schedule."
"There's a lot of physics to this problem that we're now gaining new insights into that we've never had before, and we're learning more about what it takes to build parachutes this size that can be safely deployed at these conditions," Clark said. "We're going to take all of that knowledge and feed it back to our flights for next year."
The Moon landings had to be done without an atmosphere at all, which meant using a lot of fuel, even with the light lunar gravity. Carrying that much fuel to Mars would be hugely expensive. Since the Viking Program NASA has been using parachutes to slow landers down. As they note, this has been used successfully as recently as 2012 with Curiosity. Nevertheless, as projects get more complex, and therefore heavier, it becomes harder and harder for parachutes to do what is needed on their own. If the craft is carrying people, the scale of the problem grows dramatically.
Currently under development are two types of SIAD that aim to slow the craft from Mach 3.5 to less than Mach 2 and a parachute that will reduce the speed to subsonic levels. If successful these will allow NASA to double the payload it can deliver to Mars from the current 1.5 tonnes.
Via Space.com
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