Earlier quoted context omitted.
Well Soyuz still flies and has exceptionally low human fatality rates in the last decades. So if safetey realiability is desired it could be just "buy a ride on a Souyz" for now. I think it won't be that dire. People who sign up to fly into space on a new design would probably be aware of the risks involved. Many people still climb Everest, dive into caves, and jump from clifs with wingsuits. I think there won't be a…
AFAIR there is an order of magnitude of two between the prospected prices of virgin galactic and a soyuz trip.
SpaceshipTwo crashes shortly after Mojave test flight
181–190 of 312 posts
Re: SpaceshipTwo crashes shortly after Mojave test flight
#182Earlier quoted context omitted.
I didn't say ban manned space flight. We keep trying to restart our space program by sending people to Mars. I think we should start a more extensive national unmanned space program. For example, if the Hubble, or its replacement, needs to be fixed, we should have an unmanned answer, for instance. We should start building on Mars without humans. If our machines can't do that yet, then we should invest in them until t…
I guarantee you that if there was sufficient profit motive, you'd see hundreds of companies being formed to go to space. Right now the risk makes it too expensive, so the profit isn't there. Much of the work Virgin Galactic and the others are doing will lower the cost eventually. When it gets low enough, there will be people lining up around the block to become asteroid miners, etc. Lack of willing people will never…
Not to say that there aren't large drawbacks (huge amounts of R&D, for example). Robot space travelers are also relatively uninspiring.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#183Earlier quoted context omitted.
Humans as a species will survive CO2, though, whereas asteroids conceivably can go from "not immediately threatening" to "Earth will be destroyed in a few years" without warning.
> not immediately threatening" to "Earth will be destroyed in a few years" without warning. Unless the lead time is 50-100 years, years might as well be tomorrow, it's going to kill us all either way. Even that might be stretching it. > Humans as a species will survive CO2 Maybe, personally I believe humans will cause their own extinction. I'm just not sure yet if we're going to take all life with us or not. Dealing…
Re: SpaceshipTwo crashes shortly after Mojave test flight
#184Earlier quoted context omitted.
It took 54 years to go from the Wright Brothers first flight to the Boeing 707. It took 53 years to go from Yuri Gagarin's first flight (one orbit) to this suborbital flight test.
It only took 8 / 9 years between Gagarin's flight and landing men on the Moon. That's remarkable. It's depressing to think how much closer we'd be to humans on Mars if we had focussed all the Afghan and Iraq war money on space research.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#185Gene Kranz is the gentleman sitting in the flight director's chair in the Apollo 13 movie, wearing the white vest. He helped create the Mission Control organization at NASA.
"Spaceflight will never tolerate carelessness, incapacity, and neglect. Somewhere, somehow, we screwed up. It could have been in design, build, or test. Whatever it was, we should have caught it. We were too gung ho about the schedule and we locked out all of the problems we saw each day in our work.
Every element of the program was in trouble and so were we. The simulators were not working, Mission Control was behind in virtually every area, and the flight and test procedures changed daily. Nothing we did had any shelf life. Not one of us stood up and said, ‘Dammit, stop!’ I don’t know what Thompson’s committee will find as the cause, but I know what I find. We are the cause! We were not ready! We did not do our job. We were rolling the dice, hoping that things would come together by launch day, when in our hearts we knew it would take a miracle. We were pushing the schedule and betting that the Cape would slip before we did.
From this day forward, Flight Control will be known by two words: ‘Tough’ and ‘Competent.’ Tough means we are forever accountable for what we do or what we fail to do. We will never again compromise our responsibilities. Every time we walk into Mission Control we will know what we stand for. Competent means we will never take anything for granted. We will never be found short in our knowledge and in our skills. Mission Control will be perfect.
When you leave this meeting today you will go to your office and the first thing you will do there is to write ‘Tough and Competent’ on your blackboards. It will never be erased. Each day when you enter the room these words will remind you of the price paid by Grissom, White, and Chaffee. These words are the price of admission to the ranks of Mission Control."
Video re-enactment by Gene Kranz: https://www.youtube.com/watch?v=9zjAteaK9lM
Re: SpaceshipTwo crashes shortly after Mojave test flight
#186Earlier quoted context omitted.
The other thing to keep in mind with new complex systems is that they will inevitably go thorough a phase where things are discovered over time. At the start "n" is small 1 flight, 5 flights etc. It's pretty much a given that there will be failures it's just a matter of when and how critical a failure. The failures would be loaded toward happening early on and then fixed so that one particular failure shouldn't happe…
Is it cheaper to pay by adding extra complexity into legal contracts, extra labels, and extra training across organization vs just paying up for fixing the consequences of an outlier accident?
If you're a small company you generally get to deal with each and every case, and do risk assessment up front on an individual basis. When you're big you're doing enough jobs to standardise those assessments (getting the economies of scale going), processes, and any resulting contracts. The problems get going when the supporting bureaucracy has lost track with reality and becomes a self perpetuating beast, but at least in the early stages it should be beneficial.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#187Earlier quoted context omitted.
So the pilot died in order to make Richard Branson's space tourists have a safer and more enjoyable weekend. Cool.
The pilot died trying to make a cheap, reusable orbiter a reality. The tourists are there to help pay for it.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#188Earlier quoted context omitted.
"The most stupid thing they've done is stay with an experimental rubber/nitrous hybrid engine this whole time, instead of switching to liquid/liquid engine, a well proven technology." 1. They didn't stay with rubber/nitrous. 2. Like the sort used on Antares? "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." But…
Point 1 is a good one, point 2 is not. Yes, liquid engines like the sort used on Antares, Soyuz (most reliable rocket ever built), Falcon, Proton, Atlas, Shuttle, Delta, Ariane, Saturn, and nearly every other orbital launch platform ever. Liquid/liquid engines, by any measure, are orders of magnitude more stable and well proven than hybrid rocket engines.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#189Earlier quoted context omitted.
"The most stupid thing they've done is stay with an experimental rubber/nitrous hybrid engine this whole time, instead of switching to liquid/liquid engine, a well proven technology." 1. They didn't stay with rubber/nitrous. 2. Like the sort used on Antares? "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." But…
Point 1 is a good one, point 2 is not. Yes, liquid engines like the sort used on Antares, Soyuz (most reliable rocket ever built), Falcon, Proton, Atlas, Shuttle, Delta, Ariane, Saturn, and nearly every other orbital launch platform ever. Liquid/liquid engines, by any measure, are orders of magnitude more stable and well proven than hybrid rocket engines.
"Liquid/liquid engines, by any measure, are orders of magnitude more stable."
What do you mean by stable?
A reason to go with hybrids, at least on paper, is that they are mechanically simple but throttlable, hopefully combining the simplicity of a solid booster with the ability to throttle and shutdown of a liquid.
Of course, much of that also applies to blowdown liquid systems, and I personally find a blowdown methane/lox system particularly compelling. I figure Virgin wanted to avoid cryogens, though.
Re: SpaceshipTwo crashes shortly after Mojave test flight
#190What crashed? The mother plane part, or the spacecraft part?