It's a shame that somebody had to die just so billionaires could one day take vanity space flights.
Oh bullshit ! Everything is at first expensive but eventually reaches down to the masses.
SpaceshipTwo crashes shortly after Mojave test flight
251–260 of 312 posts
Re: SpaceshipTwo crashes shortly after Mojave test flight
#252Earlier quoted context omitted.
Some say this is an "inevitable" result of pushing boundaries. No. This is the result of a poorly managed program. What they are doing is much easier than the Apollo program, which was well managed and had no in-flight failures that resulted in loss of life, while accomplishing an infinitely harder task. This is a tragedy, obviously. But the program is about six years behind schedule, been going for 10 years. The mos…
Some say this is an "inevitable" result of pushing boundaries. No. This is the result of a poorly managed program. Some of the boundaries that are being pushed are how much oversight, how meticulous, etc you have to be. In other words, how well you have to manage the program, how tight a ship you keep. Keeping a tight ship raises costs, and isn't the big emphasis of all this privatized space travel on reducing costs?
Its scary to consider, but you're basically right. This also applies to automobile/truck/aircraft manufacturing. There's always something more one can do increase safety, but it often isn't financially viable. Designing a car in which no one ever died, wouldn't be feasible, or even functional. In the 20th century, cars incrementally increased speed, which isn't so different from space-planes flying higher and higher.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#253It's a shame that somebody had to die just so billionaires could one day take vanity space flights.
Oh bullshit ! Everything is at first expensive but eventually reaches down to the masses.
No, escaping orbit is not for the masses. You will get the VR version of it.
Also what a mundane use of the technology, private industry has no incentive to do the science that needs to be done and our space program is dying so these corner cuters can take over.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#254China launches 3 rockets in one week[1]. Russia launches a resupply of the International Space Station, ready to fly just 9 hours after yet another space vehicle crashes here[2]. Say what you want about "cheap spaceflight", there is something dysfunctional going on here. This latest disaster makes me wonder if the US even has a current capability of space flight. Pinching a few pennies isn't worth it. [1] http://spac…
Pinching a few pennies is what capitalism is built on, this is why we had fertilizer plants explode, had oil rigs leak oil into the gulf. This is just the beginning if we completely rely on private space companies to do everything.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#255What this weeks events show us is that space travel is hard. Really hard. Most systems operate in extreme conditions, sometimes bordering on the improbable. Thousands, sometimes millions of horsepower in an engine smaller than a car, cryogenic liquids at -200 degrees celsius cooling a nozzle that is 3000 degrees celsius 5 millimeters away, heatshields designed to absorb obscene amounts of heat, the list just goes on…
Some say this is an "inevitable" result of pushing boundaries. No. This is the result of a poorly managed program. What they are doing is much easier than the Apollo program, which was well managed and had no in-flight failures that resulted in loss of life, while accomplishing an infinitely harder task. This is a tragedy, obviously. But the program is about six years behind schedule, been going for 10 years. The mos…
Even under the best circumstances, space travel is risky business. It may well be that this program didn't do all it should have done to mitigate those risks, but both facts can be true it's not mutually exclusive.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#256Earlier quoted context omitted.
> Seeing only the first paragraph, I already know that some rubber in the hybrid engine detached blocking the nozzle and causing the whole engine to explode. Does this same concern apply to plastic-based fuel? It does seem like a terrible idea to have people in the rocket the first time you try a new fuel mixture. "During the nine months since the previous rocket-powered test in January, Virgin Galactic switched Spac…
A hybrid has a few other failure modes too. One is called hard start: http://en.wikipedia.org/wiki/Hard_start Another - nitrous oxide can become explosive in gaseous phase. If enough of it became gas, the oxidizer tank may have exploded. There are also inherent instabilities of hybrids - higher pressure accelerates the burn, which increases pressure, which... We'll know more after they finish the investigation.
Based on eye witness accounts saying that the engine appeared to fire once more after a flameout, the hard start scenario may indeed be at play here.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#257Earlier quoted context omitted.
Some say this is an "inevitable" result of pushing boundaries. No. This is the result of a poorly managed program. What they are doing is much easier than the Apollo program, which was well managed and had no in-flight failures that resulted in loss of life, while accomplishing an infinitely harder task. This is a tragedy, obviously. But the program is about six years behind schedule, been going for 10 years. The mos…
there's no need not in this day and age to have test pilots. If they use computers, they can debug the engine in flight conditions by running maybe ten times as many test flights. Delays of months between flights are dangerous. Until you have a 1000-10,000 flights to build up operational data and envelope, this is a death trap causing unnecessary deaths.
Did you know an F1 car can drive itself around the track? It seems like there's something in human nature, at least among some people that leads them to want to drive the thing themselves.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#258Earlier quoted context omitted.
Yes, looking at the twitter feed, multiple sources state that it blew up. This means that either the tank (which takes up the whole rear half of the vehicle) failed catastrophically (unlikely; CF-wrapped tanks tend to develop hairline cracks which slowly leak out) OR the engine exploded. What's interesting is that the SS2 engine fuel was swapped out very recently for a new thermoplastic polyamide solid fuel for bette…
static wick failure, minor fuel leak, big bang. That said, I really have no clue about how these things work. That's just one scenario I could see leading to a midair explosion.
My bet is a hard start.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#259Re: SpaceshipTwo crashes shortly after Mojave test flight
#260Test pilots? In the 21st century? I find it absolutely reckless and inexcusable to require live humans riding on a prototype rocket when you have all the processing power needed to automate/remote manage the vehicle literally in your pocket. EDIT: To those downvoting, you should really check that all current spaceplanes have the capability to fly and land autonomously--Boeing X-37, Dream Chaser, even Buran was fully…
It looks like this was the first time they turned on the engine with a new fuel plastic base fuel. I don't understand why they had humans strapped in when testing an experimental fuel in an experimental rocket engine. "During the nine months since the previous rocket-powered test in January, Virgin Galactic switched SpaceShipTwo's fuel mixture from a rubber-based compound to a plastic-based mix"
They definitely tested the engines on the ground[1]. You have to give the engineers the benefit of the doubt, at the very least.
[1]: http://webcache.googleusercontent.com/search?q=cache:JBrl96U...