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NASA Releases Footage of "Flying Saucer" Braking Test, Declares Success
According to the AP, in a story carried by the San Jose Mercury News, NASA engineers insisted Friday that a test of a vehicle they hope to one day use on Mars achieved most of its objectives, despite a parachute that virtually disintegrated the moment it deployed. The engineers laid out at a news conference what they've learned in the six weeks since the $150 million high-altitude test of a vehicle that's designed to bring spacecraft -- and eventually astronauts -- safely to Mars. Engineers said they achieved the main objective: getting a flying saucer-shaped craft to 190,000 feet above the Earth at more than four times the speed of sound under test conditions that matched the Martian atmosphere. Ars Technica has (beautiful, high-speed, high-definition) video of the test that shows the parachute tearing itself apart, as well as the many parts that went as planned.
bumper sticker, y'know.
190000 feet = 57912 meters.
Just helping NASA to prevent getting their units mixed up again.
This is not the sig you're looking for.
I saw the live press release on nasa.tv (highly recommended). The principle scientists involved recognized the parachute failure, but emphasized that this is unknown territory, and the mission objectives -- which were to make an attempt and gather as much data as possible about that attempt -- were fully realized.
Yes, the parachute failed. The vehicle was going something like Mach 2 at the time, having successfully aerobraked from Mach 4.7. They got excellent video of the entire process, and only four days (or something like that) after the mission, already had revisions on the parachute in mind to prevent such failure.
This was the first of THREE planned tests. Was the mission successful this time? Absolutely not, if you expected to have a first time test succeed. But if you were looking to gather data on potential failure mechanisms, it was an overwhelming success.
And, it should be noted, the deceleration inflatable ring (which has some kitchy acronym) worked very well, and importantly, they got good data on the design and how much it deviated from perfection (1/8 of an inch deflection at Mach 4.7 ... I dare anyone to do that with rigid materials, let alone inflatables). And the blute (the droge which pulls out the main parachute) worked entirely as intended. The downside? The shape of the parachute apparently needs to be more rounded.
They are exploring entirely new territory. Who here really, really, thinks that every such testing and development mission is going to be successful? Anyone? Raise your hands, I want to see, because NASA would love to hire engineers (hell, screw NASA, *I'd* hire engineers) who have that level of talent. They're called experimental missions because the outcome is not known.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
Nobody had ever tested a big parachute at supersonic speeds at "high-altitude-on-mars-like" atmospheric density (that's why it was done at 180,000 ft..). There's been a huge number of questions about how these things deploy (or not, as the video shows), and since there aren't any wind tunnels around that run at 1 torr at supersonic speeds.. Gotta do the test.
This is also why the new capsule designs (Orion, MPCV, etc.) look like Mercury/Gemini/Apollo... they did (really expensive) testing of various body shapes back in the 60s, and everyone wants to use the same data today.
There are modeling codes for the capsule kind of application..although.. you're trusting in a model of a fairly non-linear and poorly understood problem.. hypersonic flow.. you're well beyond using Bernoulli here.
Parachutes can't slow things down much on Mars anyway which is why this is a far lesser deal than if it was designed to land on Earth. There's a nice bit on the website for the Xplane game about their Mars simulation stuff that describes it well. Their Mars flyer you can play with is like a U2 that steers like a cow and has to land at supersonic speed since parachutes can't do much to slow it down.
"Mars had canals and the Galaxy was the universe?"
Nobody on slashdot is that old
Hubble proved that other galaxies were other galaxies in the 1920's
I'm no doctor, but I think you may be undervaluing the contributions of food and oxygen.
They got it working in testing after that initial failure - and even that failure provided extremely useful high-speed video of its deployment.
Note the colossal wind tunnel. This latest, flying saucer tested parachute is way larger than that Curiosity parachute - so they've figured out a whole new testing regime. One that helpfully more closely matches conditions in the Martian atmosphere, too.
Tedious Bloggy Stuff - hooray?
You should probably NEVER watch Idiocracy then.
Chas - The one, the only.
THANK GOD!!!
This is one of those extremely RARE moments when a government team has done something great for the taxpayers. They wanted to test Mars entry hardware at a scale too large to fit into any wind tunnel that could simulate Mars and SHOCKINGLY they did NOT propose spending a decade and billions of dollars building a new super-sized "Mars upper-atmosphere simulation facility". They also did NOT propose spending billions on a whole fleet of mars-bound EELV payloads to experiment with new hardware ideas in the actual martian upper-atmosphere. This team actually did something that still has me a bit stunned (NOT that it COULD be done but rather that government people chose to do it) - they designed a scheme to achieve the sim with a balloon, a solid rocket motor, and a borrowed US Navy test range. Assuming the next two tests in the series work as planned, this team will have a proven method of testing all sorts of space probe hardware (not just for Mars) very affordably right here on Earth. Tis saves time and money and will enable lots more innovation because more testing can fit within budgets and more risks can be taken.
Well Done!
Now if we could just get the other 99.99% of the government to act even slightly this responsibly and creatively...
Spinning and de-spinning a vehicle is primarily a function of the torque applied to the object's moment of inertia. Air friction doesn't become a big factor until you reach high rotational speeds (much higher than apparant from this video).
Have gnu, will travel.