News Low-Density Supersonic Decelerator (LDSD) Atmospheric Test Flight

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NASA is focusing on developing the technologies to land the heaviest ever payloads on Mars for obvious reasons. Whether this technology will see use sooner or later is an open question. This thread will be limited to covering the test flight of the LDSD, Low-Density Supersonic Decelerator, because the technology may not have significant press updates for years after this. If that assumption turns out to be incorrect, this thread may be merged with an older LDSD update here.

A concise summary of the test flight is written in the article "NASA's Saucer-Shaped Craft Preps for Flight Test"

During the June experimental flight test, a balloon will carry the test vehicle from the Hawaii Navy facility to an altitude of about 120,000 feet. There, it will be dropped and its booster rocket will quickly kick in and carry it to 180,000 feet, accelerating to Mach 4. Once in the very rarified air high above the Pacific, the saucer will begin a series of automated tests of two breakthrough technologies.

A Star-48 engine will rocket the ship to altitude, where the airbags (or supersonic inflatable aerodynamic decelerator) will deploy at four times the speed of sound, increasing the size of the aeroshell and thus providing more drag. The 30 meter parachute will open at over twice the speed of sound.

This is what the demonstrator looks like:

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While the sled test revealed some flaws in the parachute, it remains important to test the rest of the decelerator system in a relevant environment to the Martian atmosphere: Earth's upper atmosphere. With a test in a similar environment, it may be interpreted to bring the system up to a Technology Readiness Level (TRL) of 7, close to the flight proven level of 9.

The LDSD was unable to fly on any planned launch windows between June 3-14 at "the U.S. Navy's Pacific Missile Range in Kauai, Hawaii" due to unacceptable winds. The test has been rescheduled to occur between June 28 and July 3.

Finally, a video about the test:

A recap of where the technology has been:

 

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Since the first launch window is tomorrow, the live stream should be linked directly for anybody interested: ustream.tv/nasajpl2.

The launch window extends from 8:15-9:00 AM HST, 11:15-12:00 PM PDT, 2:15-3:00 EDT, or 6:15-7:00 PM GMT.

NASA has live updates, but I'll write another post tomorrow on whether LDSD launched.

 

[RisingFury]

I wonder if will ever reach a point when the mass and size penalty for a given payload weight will be smaller for a orbit-to-surface rocket descent than it is for the heat shield -> parachute -> rocket descent.

It seems they're clawing very hard to increase drag and keep the weight down. I must say, the airbags are pretty clever. One certainly wouldn't consider some type of fabric as being reentry shield material

 

[DaveS]

LDSD is GO for launch! Watch it on NASA TV.

 

[ADSWNJ]

Update at 20:21Z (16:21 EDT) ... vehicle at 90,000 feet and ascending slowly by balloon (damn slowly, if you are used to rocket launches!!). Looking to float to 120k ft in the next 30 mins, then drop and fire the rocket to get to 180k ft for the test.

---------- Post added at 08:35 PM ---------- Previous post was at 08:24 PM ----------

20:34Z ... 100,000 ft

---------- Post added at 08:46 PM ---------- Previous post was at 08:35 PM ----------

20:46Z ... 1110,000 ft

 

[RGClark]

LDSD is GO for launch! Watch it on NASA TV.

Thanks for the link. This is a very important test to prove our capability for landing large payloads on Mars, as for manned landings.


Bob Clark

 

[ADSWNJ]

Dropped at 21:05 right on time ... rocket firing

 

[Fabri91]

Apparently a bad parachute.

 

[Quick_Nick]

Despite a failure, "The Low Density Supersonic Decelerator (LDSD) will still have gathered required data about landing heavy payloads on Mars and other planetary surfaces. As such, the mission was successful." All about the science points!

 

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I've been waiting for a video of the flight to be posted, but there doesn't seem to be one. There will be two more flights of the vehicle sometime in the future to perfect the technology. NASA released some photos of the recent test.

JPL: "First LDSD Test Flight a Success"

 

[Quick_Nick]

I just noticed that JPL posted this before the flight:
"This first of three LDSD flights will determine the flying qualities of the test vehicle. As a bonus, the flight plan also includes deployment of two new technologies -- an inflatable device and mammoth parachute. However, those landing technologies are not officially scheduled to be tested until next summer, in two additional LDSD flights."

So the partial failure occurred in a component that wasn't even scheduled for testing for another year. Bonus science ahead of schedule.

Edit: JPL after the test:
"Because our vehicle flew so well, we had the chance to earn 'extra credit' points with the Supersonic Inflatable Aerodynamic Decelerator [SIAD]," said Ian Clark, principal investigator for LDSD at JPL. "All indications are that the SIAD deployed flawlessly, and because of that, we got the opportunity to test the second technology, the enormous supersonic parachute, which is almost a year ahead of schedule."

 

[IronRain]

Another picture:

and a video:

 

[IronRain]

 

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NASA released some impressive HD footage from the flight.

NASA: "Ride Shotgun With NASA Saucer As It Flies to Near Space"

Hitching a ride aboard the 7,000-pound saucer were several high-definition video cameras. The arresting imagery is providing the engineers and scientists on the LDSD project with never before seen insights into the dynamics involved with flying such a vehicle at high altitudes and Mach numbers.

"As far as I am concerned, whenever you get to ride shotgun on a rocket-powered flying saucer, it is a good day," said Clark. "We hope the video will show everyone how beautiful and awesome the test was, and to just to give folks an insight into what experimental flight test is all about."

The high-resolution images and video clips taken during the LDSD test flight are available at:

http://go.usa.gov/N5zm​

The LDSD cross-cutting demonstration mission tested breakthrough technologies that will enable large payloads to be safely landed on the surface of Mars and allow access to more of the planet's surface by enabling landings at higher altitude sites.

[...]

 

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The next flight test will occur in June.

JPL: "Media Spun Up on NASA Cutting-edge Mars Landing Technology"

NASA's Low-Density Supersonic Decelerator (LDSD) project will be flying a rocket-powered, saucer-shaped test vehicle into near-space from the Navy's Pacific Missile Range Facility on Kauai, Hawaii, in June.

Media were on hand at NASA's Jet Propulsion Laboratory, Pasadena, California, on March 31 to witness one of the final tests that a LDSD test vehicle will undergo before shipping out to Hawaii. During the "spin table test," the 15-foot-wide, 7,000-pound test vehicle was spun up to 30 rpm to check its balance.

In mid-April, the vehicle will be flown to Kauai. During the June experimental flight test, a balloon will carry the test vehicle from the naval facility to an altitude of about 120,000 feet (36 kilometers). There, over the Pacific, it will be dropped and its booster rocket will kick in and carry it to 180,000 feet (55 kilometers), accelerating to Mach 4. Once in the very rarified air high above the Pacific, the saucer will begin a series of automated tests of two breakthrough technologies.

The supersonic inflatable aerodynamic decelerator (SIAD-R) -- essentially an inflatable doughnut that increases the vehicle's size and, as a result, its drag -- will be deployed at about Mach 3.8. It will quickly slow the vehicle to Mach 2.5 where the parachute -- the largest supersonic parachute ever flown -- will deploy. About 45 minutes later, the saucer is expected to make a controlled landing onto the Pacific Ocean off Hawaii.

[...]

 

[BrianJ]

Coverage of today's test flight now on NASA TV
http://www.nasa.gov/multimedia/nasatv/index.html

 

[MaverickSawyer]

Bad Chute! Bad Chute!

 

[Thunder Chicken]

Bummer. I am still looking for video to see this test. Did the canopy blow out like last time?

Large canopy deployment at high Mach number is a *hard* engineering problem. In the words of a dear friend, this problem is "chock full of suck". Conventional reefing and blow-out protection that would even work under such a condition would likely lead to a collapsed canopy. Worse yet, the parachute deploys into a turbulent subsonic wake, and when opened the canopy extends beyond that wake. Exceptionally hard to simulate computationally, and physical wind tunnels can't touch the size and speeds involved. The least bad option is to keep going full Wiley Coyote on it, test it full scale, and try to learn as much as possible from every prototype failure. They may need to crash a bunch of these before it is all figured out.

 

[MaverickSawyer]

Bummer. I am still looking for video to see this test. Did the canopy blow out like last time?

Large canopy deployment at high Mach number is a *hard* engineering problem. In the words of a dear friend, this problem is "chock full of suck". Conventional reefing and blow-out protection that would even work under such a condition would likely lead to a collapsed canopy. Worse yet, the parachute deploys into a turbulent subsonic wake, and when opened the canopy extends beyond that wake. Exceptionally hard to simulate computationally, and physical wind tunnels can't touch the size and speeds involved. The least bad option is to keep going full Wiley Coyote on it, test it full scale, and try to learn as much as possible from every prototype failure. They may need to crash a bunch of these before it is all figured out.

The Chute deployed partially, then the canopy shredded. The previous test was better, as there was still SOME canopy left. There didn't seem to be any functional canopy this time.

 

[Thunder Chicken]

The Chute deployed partially, then the canopy shredded. The previous test was better, as there was still SOME canopy left. There didn't seem to be any functional canopy this time.

Somewhere an engineer saw that video and scribbled in a notebook "Don't do this - BAD idea". Progress! :thumbup: