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Virgin Galactic spaceship crash


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Interesting questions! Regarding risks, I can see from a basic engineering background that the platform is inherently safer than the Shuttle (it is not stuck to the side of a large and very unstable b

This is indeed very sad, though the project as a whole has always made me deeply uncomfortable for various reasons. Olly

It never ceases to amaze me - how easy it is to travel 60 miles horizontally yet how hard to travel 60 miles vertically. My thoughts are with those left behind.  Test pilots have some control over wha

Tragedy in all terms, sadly these things happen through mans endeavors to learn and my heart goes out to all involved but especially the families of the pilots, hope the other guy pulls through.

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Sad news.

Getting into orbit will always be risky..... all the energy needed has to be stored in a small volume.... a dangerous situation however you look at it.

I expect a few of the future Celeb passengers are reassessing the risks now.

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It never ceases to amaze me - how easy it is to travel 60 miles horizontally yet how hard to travel 60 miles vertically.

My thoughts are with those left behind.  Test pilots have some control over what they do - the loved ones don't.

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Sounds like the pilot that wasn't killed in the crash is showing signs of recovery.

A very lucky man.

My thought go out to the family of the pilot who was not so fortunate.

D.C

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...the project as a whole has always made me deeply uncomfortable for various reasons.

Olly

Very sad day for all involved and I really feel for both crews' families.

Olly, why does this approach make you uncomfortable? To me, carrying the spaceship to 45k' reduces the amount of fuel it needs to carry, making it safer, and the rubber compound fuel certainly seems to be a relatively safe bet - while there is no the oxidant getting pumped into the rocket chamber, it simply won't burn meaning it should be very difficult to makeit explode - a simple puncture won't do it, for instance.

Looking at the video, I do not see the big explosion normally associated with fuel going off and suspect it is a control issue rather than anything else. The new motor is obviously suspect but a failed (new design?) oxidant pump could easily cause a control failure with erratic burn. Pure speculation, obviously, but I do not see anything particular to the WK / SS platform that makes me think it is inherently unsafe (not like the Space Shuttle, for instance!)

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Olly, why does this approach make you uncomfortable?

I can't speak for Olly but it makes me uncomfortable as well. Are they being realistic about the risks and is a quick joyride worth it? Is the craft a serious step towards better access to orbit or a dead-end development? Is it a worthwhile project or a plaything for the bored and wealthy?

I feel much the same way about people climbing Everest, after reading that it kills one-in-twenty climbers and some of the personal accounts of people in difficulty. 

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Sad news.

Getting into orbit will always be risky..... all the energy needed has to be stored in a small volume.... a dangerous situation however you look at it.

I expect a few of the future Celeb passengers are reassessing the risks now.

The Russians were putting craft into Orbit in the 1950,s.It amazes me that in 2014 we are still having these Technical problems.

My sympathies for the Dead pilots family,and best wishes for the injured pilot.

Mick.

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The Russians were putting craft into Orbit in the 1950,s.It amazes me that in 2014 we are still having these Technical problems.

My sympathies for the Dead pilots family,and best wishes for the injured pilot.

Mick.

I don't think the dangers have ever been fully overcome.... especially as each new generation of vehicles brings new problems.

Even the ancient tried and trusted Russian launch rockets still occasionally go wrong.

Perhaps the safest launch route will be via a space tether... if it is ever feasible.... just climb a ladder into space!

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I was reading something the other day that explained that the space shuttle external tank was 96% fuel by mass and 4% structure. For comparison, a coke can is 94% contents with 6% being the can itself - but a can doesn't typically need to withstand high g-forces, pressure changes and aerodynamic loads. Efficient rocketry is always going to be a difficult engineering challenge. The larger the payload the more fuel required, but then you need more fuel again to launch the extra fuel! This is the tyranny of the rocket equation, escaping from Earth's gravity well is hard.

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Are they being realistic about the risks and is a quick joyride worth it? Is the craft a serious step towards better access to orbit or a dead-end development? Is it a worthwhile project or a plaything for the bored and wealthy?

Interesting questions! Regarding risks, I can see from a basic engineering background that the platform is inherently safer than the Shuttle (it is not stuck to the side of a large and very unstable bomb that will go off with even minor structural failure) and it does naturally fall into a fail-safe condition so the risks are going to be lower but definitely not negligible - obviously this is a qualitative view rather than a quantitative one so I would not even attempt to guess how much safer...

Is it a serious step forward? Difficult to tell. I like the idea of air-launch first stage but make no claim it is the future - I actually like the Sabre / Skylon idea more. For me, though, any pioneering step is a step forward: at worst it will show that an idea will not work; at best it will give us an insight we did not have before and in between is the creation of new tech that can be reused. The throttled solid fuel motor and the fail-safe design both look like concepts we will see again.

Worthwhile project or plaything? Why can't it be both? If the rich want to fund a project that takes us a big step forward, surely this is a good thing?

There is always going to be a cost to pushing the boundaries: the pilot of this craft paid the ultimate price but went into the venture with a clear view of the risks. As such, I hope he is remembered as one of the heroes of future space flight - without people like him and projects like this, humanity will be stuck on this rock for ever.

My 2p.

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it looks like the feathering system activated. That'd certainly cause it to break up if it activated when they were still climbing.

As for it being worth it? I don't know really. It's a commercial enterprise, designed to remove large amounts of money from the bank accounts of the very rich, in exchange for a couple of minutes of weightlessness and the kudos of saying "I've been to space". I can't see it really pushing our knowledge of how to get into space...all that stuff is pretty well worked out.

What does make me uncomfortable is someone dictating on the personal risks that a total stranger is prepared to accept. A couple of people have died so far in the Virgin Galactic project (wasn't there one killed on the ground a few years ago in a tank explosion?). Meanwhile, is the US, something like 12,000 people kill themselves every year through accidental discharges of their personally owned firearms. In the UK, on average 8800 die per annum in alcohol-related deaths. Let's keep a sense of proportion and ignore the media's desire for a good headline. 

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It has been reported that one of the pilots unlocked the wing rotation assembly too soon but the wings then rotated without the rotation command being given.

http://www.newscientist.com/article/dn26493-spaceshiptwo-crash-wings-were-unlocked-too-soon.html?utm_source=NSNS&utm_medium=SOC&utm_campaign=hoot&cmpid=SOC%7CNSNS%7C2013-GLOBAL-hoot#.VFe9tPmsWcI

The rocket motor and fuel tanks have been found in tact so no explosion.

Seems a fault caused it to tear its own wings off at about Mach 1.

I feel for the pilots families but these guys knew what the risks were and if we didn't attempt stuff like this we probably still wouldn't be flying regular aircraft.

I dislike Branson intensely but I do admire his pioneering spirit.

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It goes to show (again) just how unforgiving these endeavours are. High-altitude, high-speed flight punishes any mistakes or weaknesses in design (the story of the X-15 is well worth a read). Manned spaceflight, even sub-orbital hops such as what Virgin Galactic are attempting, even more so.



I feel for the pilots families but these guys knew what the risks were and if we didn't attempt stuff like this we probably still wouldn't be flying regular aircraft.

Fixed that for you. people like Otto Lilienthal died trying to figure out the mechanics of flight.

Personally I am glad that people like this are prepared to take the risks that they take, so the envelope of human knowledge can be extended. It means that people like me can jump on a scheduled flight and see parts of the world that only 100 years ago would have meant a 3 month sea journey.

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What makes me uncomfortable is the strange mixture of 'Boys Own Paper' Bransonism for the ridiculously rich (blast off into space for a few seconds at a cost of HOW much fuel?) and real research. Is this real research? Or it is a bit of Virgin fantasizing? I don't know, but there are people who cycle to work to make our world a bit cleaner and there are others who, because they can afford to do so, will undo for a few seconds' kick, the environmental good done by hundreds of more thoughtful people.

It is far too easy to justify all technological experiments on the grounds that some of them are useful to us today. I'm reading Bill Bryson's book One Summer: America in 1927 at the moment. He describes some of the utterly nonsensical technological projects being touted at the time. They were nonsensical then, they are nonsensical now and they will, in all probablitly, always be nonsensical. I don't buy any argument that runs like this; 'They said we would never make heavier than air flyng machines but we did, so when people say we will never be able to (insert here whatever you like) they are talking rubbish.' Well no, actually, they are not talking rubbish. All sorts of things will not be done in the future.

Olly

PS Let me stress that these are views I held before the accident and don't diminish in any way my sympathy for the families of the lost pilot. That is a separate matter altogether.

Edited by ollypenrice
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But what is 'nonsensical' to one person is fun for another.

My work colleagues think I am nuts because I sit freezing my behind off for hour after hour in the dark gathering data that I could improve on by a thousand fold in 10 mins off the internet!!!! 

Surely it's about perception ??

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