Virgin Galactic Crash - Page 1
Forum section: electronics / general

author: PA0PBZ
author_rank: Super Contributor
timestamp: October 31, 2014, 08:17:01 pm
content: Darn, that's bad. Now who won that trip to space?http://www.bbc.com/news/world-us-canada-29857182

author: SeanB
author_rank: Super Contributor
timestamp: October 31, 2014, 08:20:04 pm
content: Planes crash. Cars crash as well, and a lot more often, but you still drive in them.Yes the one pilot is dead, the other badly injured. However this is just going to make the next one better as they will find out what failed, why and how to make the flight better.

author: Artlav
author_rank: Frequent Contributor
timestamp: October 31, 2014, 08:43:59 pm
content: First Antares, now this, and with a fatality this time.A sad week for spaceflight - 4 launches, two failures.

author: VK3DRB
author_rank: Super Contributor
timestamp: November 01, 2014, 02:08:20 am
content: Quote from: 3roomlab on October 31, 2014, 08:31:09 pmNo loss. The rich will just have to get their jollies some other way.

author: Falcon69
author_rank: Super Contributor
timestamp: November 01, 2014, 02:15:14 am
content: how can you have an underwater floating city?

author: Rerouter
author_rank: Super Contributor
timestamp: November 01, 2014, 02:24:36 am
content: One that is not tethered to the bottom, but is maintained at neutral buoyancy at some mid level?

author: German_EE
author_rank: Super Contributor
timestamp: November 01, 2014, 07:56:48 pm
content: Yes, going into space is risky, but if they offered me a seat on this thing I would be there in a heartbeat.

author: rob77
author_rank: Super Contributor
timestamp: November 01, 2014, 08:08:40 pm
content: i wouldn't try the virgin galactic flight - it's just a sub-orbital flight after all and apparently too much risk is involved..... but i would definitely try the old school Soyuz - that's a powerful beast and actually got a good safety recordbut of course i will never try out either of those because i'm short of many many millions for that

author: calexanian
author_rank: Super Contributor
timestamp: November 01, 2014, 08:58:28 pm
content: I think Elon is taking out every other private space venture one at a time! hahahahaha.. First Orbital Sciences, not Scaled Composites, and now look out Boeing!Seriously though, I hope this does not set back private space too far. We are basically screwed since the government gutted the space program without the availability of these private firms.

author: Framebuffer
author_rank: Newbie
timestamp: November 01, 2014, 11:40:08 pm
content: Space's hard. They'll figure out what they've messed up and carry on. I personally have some hope they'll be able to get another spaceship up and running in no time

author: AlfBaz
author_rank: Super Contributor
timestamp: November 02, 2014, 01:51:56 am
content: ...and this is at least one good reason NOT to put your company logo on prototypes

author: Bored@Work
author_rank: Super Contributor
timestamp: November 02, 2014, 04:55:01 am
content: Quote from: AlfBaz on November 02, 2014, 01:51:56 amVirgin galactic is already busy distancing themselves from the accident. Oh sorry, "serious anomaly", or "mishap". Oh, how I hate this PR speak. Stupid wankers. And I hate it even more when news sites copy that PR speak.The first three paragraphs on VGs web site readQuoteNote how busy they were to add "Scaled Composites" to every paragraph. They point to Edelman for more information, a very large PR companies who probably also wrote VGs statement. And Edelman is not stranger to unethical work.

author: zapta
author_rank: Super Contributor
timestamp: November 02, 2014, 06:51:03 am
content: Quote from: German_EE on November 01, 2014, 07:56:48 pmLooking at the picture, both seats are probably smashed by now.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: November 02, 2014, 07:07:44 am
content: Quote from: Bored@Work on November 02, 2014, 04:55:01 amBut you repeat yourself.

author: Timmay
author_rank: Contributor
timestamp: November 02, 2014, 08:44:19 am
content: Quote from: calexanian on November 01, 2014, 08:58:28 pmWell governments just do it better, look at the Soyuz and Atlas V rockets. They have very high reliability rates. As for the Antares I don't know until the release the report, but so far it was an RSO call. The killed it either from the spotters down low, I think they hit the alarm for two reasons (one it was quickly destroyed and two no one was hurt which means they got into the shelter). Musk talked about how he was weary of them using the old NK engines from the Soyuz family (which Orbital Sciences is using). At first I wanted to blame it on those old engines but deviation from flight could be many things. As for Boeing (and Lockheed) they are now on their 50th successful launch so there is that. The Virgin thing I have heard was possibly from new propellant to get more performance from it and I am inclined to agree as the initial burn of had good color and shape but prior to the destruction pictures show some intensity loss and sputtering (but that isn't enough to know if it was a burst or explosion).Either way, I wouldn't be worried, aviation manuals are written in blood, and the pilots life will not be in "vain" for whatever its worth, new rules/procedures/processes will come from it. They know when yanking sticks the risks. I have lost more friends on experimental aircraft and military aircraft than I care to discuss. I was even involved in a engineering investigation from a loss of a friend and two pilots on a helicopter I last worked on and signed safe for flight (in my relief it was found to be pilot error). It sucks, everyone involved in the business know the risks from the aircraft wash team to the pilots. Just a dangerous business.

author: SeanB
author_rank: Super Contributor
timestamp: November 02, 2014, 09:15:26 am
content: That investigation is a nasty one. I was in one of them, even though the cause was engine failure from bird ingestion, and I did avionics not related other than sharing a power source. Still was a lot of anxious weeks during the investigation, having them come in and grill you over all the paperwork and having it all being examined and the smallest errors noted and shown to you.

author: German_EE
author_rank: Super Contributor
timestamp: November 02, 2014, 11:08:50 am
content: I strongly suspect that the 'anomaly' thing is the way that people in the aerospace industry normally think. When Apollo 13 went bad the transmissions from the craft were as follows:Jack Swigert I believe we've had a problem here.Jim Lovell Houston, we've had a problem. We've had a MAIN B BUS UNDERVOLT.Fred Haise Okay. Right now, Houston, the voltage is—is looking good. And we had a pretty largebang associated with the CAUTION AND WARNING there. And as I recall, MAIN B wasthe one that had had an amp spike on it once before.Fred Haise In the interim here, we're starting to go ahead and button up the tunnel again.These are professional military men talking here, test pilots and combat veterans who just deal with anything that comes along. Until the cause of the Spaceship Two accident is known then it is just an anomaly and whilst 'the spaceship blew up and crashed' is more descriptive it adds nothing to the discussion.

author: Rick Law
author_rank: Super Contributor
timestamp: November 03, 2014, 03:36:16 am
content: Quote from: German_EE on November 02, 2014, 11:08:50 amAnother example: In 1986, when the Space Shuttle Challenger blew up live on TV, with pieces flying all over the place, the accompanying audio from flight control was "...we have a major malfunction..."I would have said "we got a gigantic explosion, holy cow, that was massive. I think everybody probably just got killed..." but such out-burst would cause panic and perhaps over reaction. My guess is, the understatement is a trained response so as not to invoke panic or over-reaction. They are trying to avoid "The Hindenburg moment" on radio... I think.

author: coppice
author_rank: Super Contributor
timestamp: November 03, 2014, 04:16:43 am
content: Quote from: Timmay on November 02, 2014, 08:44:19 amSoyuz might have been an entirely government programme, but Atlas V and other American rockets were just financed by the government. All the work was don't by private industry. Sometimes there was tight NASA oversight, and sometimes there wasn'tQuoteI think you will find Orbital Sciences uses engines from the abandoned Soviet attempt to put men on the moon. These are radically different from Soyuz engines, and quite novel in their pumping scheme.

author: AlfBaz
author_rank: Super Contributor
timestamp: November 03, 2014, 06:03:22 am
content: Quote from: coppice on November 03, 2014, 04:16:43 amLike Thiokol not reporting to NASA problems with the o'rings prior to the challenger disaster

author: Artlav
author_rank: Frequent Contributor
timestamp: November 03, 2014, 01:07:11 pm
content: There is evidence that the problem wasn't the engine at all, but the tail feathering getting unlocked and deployed, tearing the ship apart by aerodynamic forces.Possibly a pilot's error combined with bad luck/bad controls design.NTSB briefing:Quote from: Timmay on November 02, 2014, 08:44:19 amUnfortunately, in spacefilght what was cutting-edge tech in the 60s-70s often remain cutting-edge tech today.Quote from: coppice on November 03, 2014, 04:16:43 amI once heard oxidizer-rich staged combustion engines described as "running at razor-thin margins between BOOM and BOOM".But they are among the most efficient rocket engines that exist so far.

author: HP-ILnerd
author_rank: Frequent Contributor
timestamp: November 03, 2014, 04:20:19 pm
content: Quote from: coppice on November 03, 2014, 04:16:43 amWhole documentary on it:

author: SeanB
author_rank: Super Contributor
timestamp: November 03, 2014, 05:09:22 pm
content: Quote from: AlfBaz on November 03, 2014, 06:03:22 amThiokol did report the o ring erosion issue, but it was considered not an issue, as there were 2 that had to erode through. Of course they also did not note that the temperature range of the rings was very small, and that cold prior to launch increased erosion. The redesign had extra strength there and different rings and such to increase the seal resilience. Nasa management was concerned about the launch window, and relegated the other concerns to a secondary role.Classic pork barrel though, the designers wanted a shorter SRB, as this would have saved a section, and given the same boost in a lighter package. But they had to use the Thiokol design, and this was limited by the shipping method of rail transport, as a barge would have involved taking them through the Panama Canal every time. The other bidder was wide like the engineers desired and local, with shipping via canal.

author: AG6QR
author_rank: Frequent Contributor
timestamp: November 04, 2014, 12:09:08 am
content: Quote from: Timmay on November 02, 2014, 08:44:19 amLet's look at the numbers. The SpaceShip Two has had 54 test flights, with one recent failure. True, those test flights didn't reach space, much less reaching orbit. So one can argue they're not in the same league as the established government programs and shouldn't be compared. But for the sake of argument, let's compare them. The failure rate seems to be around 1 in 50 so far.The Soyuz, along with the US Space Shuttle, both have had a roughly 1 in 50 failure rate for human spaceflight.The Mercury, Gemini, and Apollo programs didn't have enough flights to establish with certainty whether they would have been better or worse than a 1 in 50 failure rate, but when you combine them, they had around 30 total missions with one loss of crew and vehicle on the ground (Apollo 1), plus a close call with Apollo 13.The Atlas V has had 50 total launches, with 49 successes and one partial failure (craft reach orbit, but lower than planned). That's impressive, but a single failure could bring it to the neighborhood of 1 in 50 failure rate.The sample sizes for all of these programs are small. When the numbers are so small that a single different outcome could skew the results drastically one way or another, it's difficult to make precise comparisons of statistics.There is no space program, government or private, that has a proven track record that can demonstrate, with statistical significance, a failure rate of less than about 1 in 50. That's disturbing, and shows just how hard space is, no matter who is doing it. This is not the same as airline travel, or even automotive travel. It's not routine, and it won't become really routine until we have a LOT more experience.