SpaceShipTwo 'Enterprise' crashes

[HawkMan]

shouldn't the unlock have an automatic "lock" system that prevents unlocking at dangerous speeds unless you also flip an override.

[DocM]

With NTSB now appointing a team to look at the human-spacecraft interface that may be what comes out of this. It should also be easy to implement a feather interlock tied to the mach guage given the glass cockpit.

[DocM]

Things are starting to crystallize around co-pilot error,

Washington Post....

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A number of sources, who spoke on the condition of anonymity because the company has forbidden interviews with the media, described seeing Alsbury unlock the feather and then appear to realize there was an error, moving quickly as if he was trying to shut off the motor, but it was too late.These sources said that within the company, there is a growing recognition that Alsbury, the co-pilot, unlocked the feather early, although it is not clear why.

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Vvirgin Galactic statement,

Statement from Virgin Galactic

04.11.14

Over the past several days, we have received new information about the tragic incident that resulted in the death of Scaled Composites co-pilot Michael Alsbury and injuries to pilot Peter Siebold. Our thoughts and prayers remain with the families and friends of these brave men. The following summarizes what has been learned from the formal investigation.

On October 31, 2014, SpaceShipTwo conducted a powered test flight and experienced a serious anomaly that resulted in vehicle failure. The National Transportation Safety Board (NTSB) is in charge of the investigation and we are cooperating fully with their work. While we cannot speculate on the causes of the incident, the NTSB has provided important information about the facts surrounding this case and in their final onsite press conference they described a timeline of events based on the telemetry data in their possession. The investigation will now continue offsite.

Based on information they have released about their investigation to date, the NTSB has recovered the intact engine and rocket propulsion fuel tanks with no signs of burn through or mid-air explosion. This definitively dismisses the premature and inaccurate speculation that the problem was related to the engine or the fuel.

The NTSB also evaluated the vehicles feathering mechanism, which is the unique technology that turns the wing booms into position for re-entry. The NTSB indicated that the lock/unlock lever was pulled prematurely based on recorded speed at the time, and they have suggested that subsequent aerodynamic forces then deployed the feathering mechanism, which resulted in the in-flight separation of the wings and vehicle. At this time, the NTSB investigation is still ongoing and no cause has yet been determined these are purely facts based on initial findings. We are all determined to understand the cause of the accident and to learn all we can.

At Virgin Galactic, safety is our guiding principle and the North Star for all programmatic decisions. Our culture is one of prioritizing safety as the most important factor in every element of our work, and any suggestions to the contrary are untrue. We are committed to learning from this incident and ensuring something like this can never happen again. To that end, we will work closely with the NTSB and will focus intense effort on its findings and guidance.

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[+Warwagon MVC]

I wonder if you could download this into Flight Simulator X

[SarK0Y]

The flight card says the LOCK lever is not to be UNLOCKED below 1.4 mach. Most likely because of transonic turbulence.

in fact, i no'll be surprised, if it will need reconstruction from the very scratch. the're no an answer how given scheme could handle emergency state:

 

1. any issue of feathers means deadly crash.

2. any issue of engine means deadly crash.

3. many another minor troubles could provide the same way.

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Shuttle seems astonishly more reliable & safe. Branson said about baby steps of space tourism, but (sorry to say) why to invent a wheel, if all stuff for suborbital flights have been put on table??? Theoretically it's possible to set ss2 on strong foot w/ given scheme. Meanwhile, price shall skyrocket sicko-insane, it's gonna be even more costly than conventional space flights.  very Branson's problem: he just has delegated project to nerdy guys w/o any clue in what they're wanna do.

[DocM]

Shuttle was a death trap, as 14 graves can attest.

ANYTHING goes wrong in the first 3 minutes of flight and the crew is dead. (Challenger)

A tile falls off and they're at very high risk. (several missions, with damage to underlying structures)

A crack in the RCC leading edges or landing gear seals and they're dead. (Columbia)

But this is irrelevant because SS2 isn't an orbital spacecraft. It's suborbital.and not subjected to the same forces.

As to SS2, what seems to be necessary is an interlock preventing the feather between mach 0.80 and mach 1.20.

There is not enough data to show an engine defect. We thought there was 2 days ago, but that was wrong.

[HawkMan]

The tiles on the shuttle seems to have been mostly an age issue, they worked fine for decades. But the shuttles never got new replacements. And had they rebuilt them with modern technology they could have had working escape capsule and a better one piece one use replaceable heat shield. Personally I say they should have kept working on the aeorospike powered shuttle replacement with a 36 hour cycle time before it was ready for relaunch.

 

To bad all decent projects where cancelled or miniaturized and given to the military. The "private" shuttles under development look like east block cars from the 60s.

[SarK0Y]

@DocM

 

We're very lucky more Shuttles didn't burn during re-entry.

the're no luckiness -- Just good Engineers to keep thing on-run. + it'd be enhanced as well. However, yeah -- Soyuz-like vehicles much more safe & cheap consequently. 

 

As to SS2, what seems to be necessary is an interlock preventing the feather between mach 0.80 and mach 1.20.

one droplet, 2nd one etc & you get a Sea :) are you sure how many 'trifles' there have to be "healed" to make thing flying safely???

 

There is not enough data to show an engine defect. We thought there was 2 days ago, but that was wrong.

i don't say this event was because of the engine. i Just mentioned the future flights must be more protected against engine issues. if ss2 doesn't take right altitude, chance to airbrake becomes very vague: flow loads get too high to angle feathers.

[HawkMan]

Soyuz has limited practical use compared to a shuttle and isn't really comparable. As for it being safer... well its the only option they have, but if the launder blows they're as dead as the shuttle crew. Other than that its just a cone with a heat shield.

[SarK0Y]

Soyuz has limited practical use compared to a shuttle and isn't really comparable. As for it being safer... well its the only option they have, but if the launder blows they're as dead as the shuttle crew. Other than that its just a cone with a heat shield.

actually, it's wrong to compare Soyuz & Shuttle so strightly:

 

1. Soyuz is good to rotate crew safely for orbital stations.

2. Shuttle is the space mule, it's good to return weighty things on ground.

3. Meanwhile, Shuttle is very restricted to take weighty cargo off the ground. So the best approach would be Energia-like rocket.

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In short, optimal variant is to have purpose-devoted solutions. all-in-one things need to run more advanced hi-tech than state-of-the-art ones.

[DocM]

The problem with shuttle tiles wasn't age, it was fragility. They're basically a silica glass foam with a solid overlayer.

You can easily crush Shuttle tiles with your hand. Any tank foam, ice or other debris and they sustain damage - sometimes hundreds of them on each flight. STS-27 (Atlantis) had more than 700 tiles damaged during launch.

Soyuz has fired its launch abort system once to save the crew at launch, decades ago.

On the other hand, 2 Soyuz crews have been lost by; malfunctioning parachutes (Soyuz 1), and a cabin vent valve accidentally opening at service module separation exposing the crew to a vacuum (Soyuz 11).

[Tews]

I wonder if you could download this into Flight Simulator X

 

Tacky WW, tacky.. :angry:

[DocM]

Marc Zeitlin, a former Scaled Composites engineer, shared this,

There is approximately a 2.5 second window during the whole 70 seconds of powered flight during which unlocking the feather is catastrophic. The feather is supposed to be unlocked at the end of the gamma turn, at approximately M1.4, still during powered flight (obviously) as a check to ensure that feathering can occur when required after burnout. This was part of the failure mitigation strategy, given the lock system unlock failure probability estimates.

The unlucky part here was that the error in unlocking was performed about 10 seconds or so early, at M0.95 rather than M1.4, and during that 2.5 second window of vulnerability.

[DocM]

ParabolicArc has posted a series about the SS2 Enterprise accident. Segment links and setup in the link below. A good read. 

http://www.parabolicarc.com/2015/11/12/3-seconds-disaster-spaceshiptwo-accident-3/

[malenfant]

Excellent articles. Burt Rutans claims in the final article perked my interest. I wonder what he has in mind? 

[Draggendrop Veteran]

Yes...excellent articles...Thanx for posting Doc...could not believe my eyes as the damage unfolded....uuugh....

[Draggendrop Veteran]

Virgin Galactic to Begin SpaceShipTwo Flight Tests Next Month

 

VSS Unity roll out on Feb. 19, 2016. (Credit: Virgin Galactic)

 

Quote

Virgin Galactic says it will begin flight tests with its second SpaceShipTwo in August at the Mojave Air and Space Port in California, a company official told Bloomberg News.

 

The tests, which will likely begin with captive carry flights, will come nearly two years after the first SpaceShipTwo crashed on Halloween morning 2014. Co-pilot Mike Alsbury died in the accident.

 

The story says that powered flights of the suborbital space plane will begin in 2017.

http://www.parabolicarc.com/2016/07/09/virgin-galactic-spaceshiptwo-flight-tests-month/

 

with reference to this article.....

 

Virgin Galactic to Restart Flight Tests of Commercial Spaceship

 

Virgin Galactic's SpaceShip Two VSS Unity spaceship during its roll-out ceremony at the Mojave Air and Space Port in February. Photographer: Ricky Carioti/The Washington Post via Getty Images

 

Quote

Virgin Galactic Ltd., the commercial space company founded by billionaire Richard Branson, is set to resume test flights next month in a new spaceship that replaces the craft that crashed in a fatal accident two years ago.

The company is due to complete ground tests in August and move to testing the vessel in the skies while attached to an aircraft, according to Jonathan Firth, vice president at Virgin Galactic. The spaceship, named Unity, is scheduled to begin the final stage of testing -- independent, fully powered flights -- next year.

Branson is vying with Amazon.com founder Jeff Bezos’s Blue Origin to be the first to ferry private adventurers to the edge of space in reusable craft. Virgin Galactic’s flights have been grounded since October 2014, after its SpaceShipTwo broke up in mid-air, while Bezos’s offering has successfully fired and landed its craft multiple times.

Virgin Galactic has yet to set a date for the first commercial flight, and Firth said this would depend on the results of the tests.
‘More Conservative’

“We’ve thrown out so many dates in the past that we weren’t able to keep to, we’re being a bit more conservative this time,” he said in an interview in London.

The designer of both spaceships, Scaled Composites LLC, should have protected against the flaw that caused Unity’s predecessor to tear apart, the U.S. National Transportation Safety Board has said. The crash occurred when a pilot prematurely activated a brake, killing him and injuring a co-pilot.

The new spaceship has a similar design to the original one, which underwent about 30 powered flight tests before the incident. 

Virgin Galactic has almost 700 bookings at $250,000 a ticket, Firth said. The cost could fall to less than $100,000 if other entrepreneurs can successfully create competing flight programs, stimulating demand and pushing down prices.

Virgin Galactic also has a satellite business, which will use an old Boeing Co. 747 jumbo jet from its sister airline, Virgin Atlantic Airways Ltd., to fling rockets into the atmosphere. It’s scheduled to begin flight tests in late 2017. Firth said the unit could be split off into a separate company using the Virgin brand.

“If you look at the history of Virgin, we’re always thinking of the structure of our organizations,” he said. “I wouldn’t discount anything.”

http://www.bloomberg.com/news/articles/2016-07-08/virgin-galactic-to-restart-flight-tests-of-commercial-spaceship

 

This could take some time......

[Beittil]

Knowing VG it will be going at an absolute snail pace...