MattRob
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chiro said:Thanks for the reply.
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Also what is wrong with "oil based society"? Most of the energy we need comes from oil. Fair enough it doesn't power space vehicles leaving earth, but it damn well powers most of the stuff right here on earth. How the hell is that a buzzword? There are reasons why countries guard their oil and why wars are fought over resources.
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Ah. There's nothing really wrong or that I disagree with in that post. I was under the incorrect impression you were mixing science and politics, but now I see you weren't. Sorry 'bout that. Speaking of mixing science and politics, a major pet peeve of mine (or more specifically, bending science to match political goals)...
Ryker said:So if you disagree with twofish, what feature of communism was it that killed the economies then? Because you do realize he did mention one such feature of the "communist-flavored iteration of Marxism", right? You seem to be just tossing the word around without any substance behind your "arguments", and I find it very odd that people in this day and age still see the world as "red" and the rest. I guess the conservative US propaganda really does still hold sway over the fears of Americans.
I really don't think this belongs in this conversation. I've got quiet a number of strong words against it but this isn't the place for that, let's try to stay on-topic and not rail out against other political views we disagree with or call names...
That's the nice thing about science. At least it tries to be objective, and usually it is very much so.
So, about what I said earlier, is there any fundamental or economic reason why first stage rocket boosters can't be designed more like aircraft? The extremely high Specific Impulse of airbreathing engines should mean that it wouldn't be too hard to have turbofan engines, wings, and minimalistic fuel to return to a landing strip. Sure upfront costs on development and vehicle construction would be high because it's unconventional, but if the goal is to make spaceflight more routine like air flight, why not make it more like air flight? Rocket planes have been around since the early 1940's, at least. (To be fair, with not nearly the Delta-V of any space lift 1st stage boosters...) Why not use a mothership / child aircraft ( spacecraft ) configuration, which has existed since, also, at least WWII. These technologies, unlike current conventional designs, don't require some of the huge logistics or maintenance, though they've certainly had the test of time. Ask any engineer at Virgin Galactic.
Less Logistics and maintenance means shorter turnaround time. Shorter turnaround time means more routine flight, lower prices, and all the goodies that brings.
I've heard it mentioned a few times that rockets are better because they punch through the atmosphere faster. But what if the turbofan engine could be the primary propulsion until it climbs to a high altitude? The mass ratio for a turbofan to climb to ~30,000 feet and later to return to the airstrip would be insignificant, almost. Not to mention a majority of the jet fuel would be used to reach that initial altitude, so it's not there to weigh down the rocket when it fires it's real engines, rockets, whatever kind they be.
Then there's the case of getting an effective mass ratio out of an aircraft design. The shuttle should've proved that's possible, by maintaining a mass ratio of ~6.4 (without SRB's, with ET). External tanks being a technology that has also been around since WWII. I suspect complexity and price of External Tanks could be greatly reduced if they didn't have to hold Liquid Hydrogen. Though that would necessitate a high ~7 mass ratio for each stage, meanwhile LOX/LH2 would only require something around 3.7 - and get this: The Boeing 747 has a mass ratio of 2! 3.7 would really be something...
EDIT: @ D H, Ah, that's meters/second, those are theoretical maximums as opposed to current designs. Current rockets are about at the theoretical maximum of their performance, so perhaps it's not totally unreasonable to suspect scramjets could reach their theoretical maximum within a few decades. And why not remember we did what was impractical, unfeasible, and uneconomic? I think more of the problem with shabby ideas is some being proposed more for an individuals' personal gain or from a business perspective are mixed in with real, objective scientific ideas.
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