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NASA's Orion Mock-Up Fails Parachute Test
leetrout writes "Fox News has the story on a parachute test failing on a mock up of the new Orion spacecraft. 'This is the most complicated parachute test NASA has run since the '60s,' said Carol Evans, test manager for the parachute system at NASA's Johnson Space Center in Houston. 'We are taking a close look at what caused the set-up chutes to malfunction. A failure of set-up parachutes is actually one of the most common occurrences in this sort of test.' Space.com has the video."
Not really; parachutes are actually pretty finicky pieces of equipment. Parachutes for people are something we've been doing for about 80 years now, they are produced and packed with incredibly exacting care, and every parachutist actually carries two parachutes, just in case. And you *still* occasionally hear about parachute accidents where the parachute didn't work right. The main problem is that it is very easy for the rigging to get tangled, and when that happens the parachute doesn't open correctly and the whole deal drops like a rock.
Actually, there were no reserve chutes; after the "setup" chutes cut away, two chutes are supposed to open to orient the craft, and then after they cut away three deployment chutes pop which pull out and deploy the three main chutes. Due to the craft not having been set up correctly (where "correctly" is in reference to the conditions that the craft should be flying under at that point in the descent), the craft's landing chutes could not do their job, and the test is essentially void.
They mention that Orion uses the same basic chute system configuration as the Apollo craft did.
-- Humans, because the hardware IS the software.
Additionally, what failed was not the parachute system destined for the actual mission, but instead the parachutes that are used to stabilize the capsule away from the delivery craft so that the real system can be accurately tested. The test didn't fail, the set-up for the test failed.
True as well as witty.
If you read TFA, you will see that the capsule was falling faster than the intended deployment speed, causing the drogue chutes to cut away before the main chute could be deployed.
So this clearly a bug in the test procedure. The test procedure was testing outside the intended speed range. Whether this was at a speed the system should ultimately work at or not, we don't know from the information given.
In other words, the test failure doesn't necessarily show the parachute design, fabrication or installation was faulty. Of course this must be sobering for anybody who's on the short list to be on the first team that relies on the system.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
A Parachute Test Vehicle (PTV) test failed at El Centro, Calif. The PTV was released from a B-52 aircraft at 15,240 meters and the drogue chute programmer was actuated by a static line connected to the aircraft. One drogue chute appeared to fail upon deployment, followed by failure of the second drogue seven seconds later. Disreefing of these drogues normally occurred at 8 seconds after deployment with disconnect at deployment at plus 18 seconds. The main chute programmer deployed and was effective for only 14 out of the expected 40 seconds' duration. This action was followed by normal deployment of one main parachute, which failed, followed by the second main parachute as programmed after four-tenths of a second, which also failed. The main chute failure was observed from the ground and the emergency parachute system deployment was commanded but also failed because of high dynamic pressure, allowing the PTV to impact and be destroyed. Investigation was under way and MSC personnel were en route to El Centro and Northrop-Ventura to determine the cause and to effect a solution. TWX, George M. Low, MSC, to NASA Hq., Attn: Apollo Program Director, Jan. 11, 1968.
Source: http://www.hq.nasa.gov/office/pao/History/SP-4009/v4p2h.htm
For those that hate space.com:
http://mfile.akamai.com/18566/wmv/etouchsyst2.download.akamai.com/18355/wm.nasa-global/Constellation/CDT2_256.asx
See also:
http://www.nasa.gov/mission_pages/constellation/orion/pa_chute_test.html
I hold it, that a little rebellion, now and then, is a good thing. -- Thomas Jefferson
The parachute system is so complex because they need to slow the capsule down in stages before full deployment. If you just popped the main parachutes after rentry, they'd tear clean off and the passengers/payload would continue unabated until they rejoin the surface. Permanently.