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Old July 13 2012, 10:07 PM   #159
Rear Admiral
Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

I would have no problems with hydrazine depots myself. That's what von Braun wanted, but folks are really risk averse today. That Briz failure spooked a lot of people. Robustness seems key:

There is some interesting news: The stratolauncher doesn't seem to be the only air-launched concept being looked at--and I'm not just talking White Knight 2

Dream Chaser news

Orion (wingless designs) capsule still best for returning from the Moon/Mars

Liberty has made the news again. Liberty isn't just the Ariane 5/SRB--ATK makes a near all composite capsule. Strange mid-service module cargo design here:

newtype_alpha wrote: View Post

Actually, I'm pretty sure ULA is going to wind up being the Junior Partner to Sierra Nevada;
I wish I could believe that--but Boeing already has their own capsule that they would like to sell:

This is also to be launched by Atlas, so Dream Chaser will wind up having to deal with a conflict of interest. This is why the downselect must be Dream Chaser and Space X, in that each compliments the other. So write your Congressmen.

Dream Chaser is profiled on page 37 of the July 2 issue of Aviation Week and Space Technology, where Mark Sirangelo was interviewed. He went so far as to say that since there are no outside investors or venture capitalists, they "carry twice the industry average in R&D budget." There is talk about their great down mass capability, their BOR-4/HL-20 legacy. They bought up a lot of equipment from elsewhere--the old American Rocket Co for the hybrid motor, and Starsys Research, MicroSat, etc.

The braking mechanism for Curiosity is also theirs in part, so that may be a black mark if something goes wrong."Unlike Space X, which has moved as much component fabrication as possible in-house, Sierra Nevada usually goes outside for equipment it does not already manufacture." That worries me a little, in that it is always good to do things in-house so as to not open yourself up to some other companies problems--but this combination of in-house capability plus market savvy is one more reason a Space X/Dream Chaser combo is needed so as to compare notes.

On Page 32 of the July 9 issue of AV Week, there is a nice write-up on Space X and Sea Launch, and how Boeing's all electric bus 702SP satellite bus will allow new markets for Musk, and how ULA is "essentially out of the market for Commercial launches."

What that means is that they will be even more fierce to go after the manned capsule movement.In the UK, they wanted their own planes, like TSR-2. They got force fed the F-111 because it was to be cheaper--and wasn't. But the damage was done. I fear that ULA might try to give the old Avro Arrow treatment to Dream Chaser.

Spaceship 2 gets a nice article on page 119 of the July 9 issue. called Final Countdown.

More news:

newtype_alpha wrote: View Post

Interestingly, the Soviets tried the same thing with the Energia rocket
That was at the end of the USSR, after the farce that was a war in Afghanistan depleted their budgets--along with the Baikal Amur Mainline. Rails ate up a lot of their budget. In late 2002, the full electrification of the Trans-Siberian Railway was at last announced--after 74 years of work. Energia was falsely blamed for the collapse of the USSR. Their attempts to match the USA in blue-water navy-to-blue water navy, Bomber-to-bomber is what broke them. Nikita wanted an all missile system--in that it would actually be cheaper. Had Energiya been built instead of N-1--or had at least been done earlier, things would have been different.

newtype_alpha wrote: View Post
LOL not by a longshot. It's a result of the fact that what they're essentially trying to do is a propulsive landing on mars with a robotic vehicle the size of a jeep
They are going to need huge aeroshells for anything larger:

This earlier article I found to be funny:

Rob Manning the Chief Engineer for the Mars Exploration Directorate says that: “the problem is that right now the heat shield diameter for a human-capable spacecraft overwhelms any possibility of launching that vehicle from Earth....The structure would need to be about thirty to forty meters in diameter. The problem here is that large, flexible structures are notoriously difficult to control. At this point in time there are also several other unknowns of developing and using a Hypercone."

But then he goes on to say: “Mars is really begging for a space elevator,” said Manning. “I think it has great potential. That would solve a lot of problems, and Mars would be an excellent platform to try it.

So let me get this straight. He has already dismissed future HLLVs out of hand, but then in the same breath talks about a space elevator tens of thousands of miles tall, dwarfing any HLLV. That anti-heavy-lift mindset is what is hobbling us. An HLLV is just a water tower. The best thing is to just build an SLS replacement launcher in about 30-50 years time that is itself 30 meters across and just launch the aeroshell in one piece. Now if you think that sounds large, it is--but not compared to other things we build, like the Troll platform or Very Large Crude Carriers (supertankers)

Heck a reusable HLLV like NEXUS has a bulkhead very broad and shallow--very like a Mars aeroshell would need to be:

Certain Shuttle-C designs had rigid aeroshells the width of an orbiter.

And there are other LV designs that allow for very wide structures as payloads--at least potentially:

More do-able: OTRAG

Parallel staging allowed very large payload diameters up to 30 m and thrust acceleration to be limited to a maximum of 3 g to allow lighter payload and space vehicle structures. The low cost was mainly achieved by simple design, lack of moving components, cheap commercial materials and components, and large volume production of tens of thousands CRPU's per year.

But that would be a later step. On Page 22 of the July 2, 2012 we see an article called Going Long: One way Orion could take astronauts to Mars. "John Karas VP and general manager of Human Spaceflight at Lockheed Martin Space Systems...argues the mission would be affordable based on NASA funding history...SLS should be cheaper than a shuttle because it uses shuttle-heritage hardware in a simpler configuration." Now this would be using a halo orbit and astronauts would control rovers via telepresence.

Maybe this will help:

More on the Z-pinch

My point in all this is for folks to understand that rocket size has been stagnant. In the past, engineering accelerated beyond science. The amount of brain power that went into the development of the Beagle was more than the product of any one man--and I would dare to say that Darwins discovery took less brain power than what went into that ship.

With spaceflight, the science and engineering coupled together--but sometimes got into each others way. When Brunel came up with the Great Eastern, he thankfully didn't have an oceanographer trying to raid his budget for a smaller FLIP ship. But if the former had not come along, the latter would never have been made possible. In short, planetary scientists should stop trying to interfere with rocket growth and should embrace it. In the current political climate, getting SLS killed doesn't automatically mean you free its budget up for other things. More likely is that the equipment sets around, and the money is cut, leaving everybody sour. Congress supports SLS and will support payloads for it. People need to be thankful.

Last edited by publiusr; July 14 2012 at 12:00 AM.
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