Going half-way around the globe is not much different than getting into orbit. (From an energy and velocity point of view)So you're not looking for an airplane. You're looking for what you already have - a first stage that returns to base, and a capsule+US that lands propulsively at the destination airport.It is an expensive way to travel, but putting wings and landing gear on it is not going to make it cheaper.
Merlin 1D would be overpowered for anything but a huge spaceplane.
Quote from: meekGee on 11/14/2012 08:34 pmGoing half-way around the globe is not much different than getting into orbit. (From an energy and velocity point of view)So you're not looking for an airplane. You're looking for what you already have - a first stage that returns to base, and a capsule+US that lands propulsively at the destination airport.It is an expensive way to travel, but putting wings and landing gear on it is not going to make it cheaper.I've checked and there basically are very few cities that are literally each other's antipodes. An antipode is basically where you'd come out of the earth if you had tunneled straight though the core and out the other side. For instance, the antipode of Chicago is just off the southwestern coast of Australia near the city of Perth. I think this is because most of the earth's landmass is in the northern hemisphere. But thanks to that geographical quirk, I think you wouldn't need to fly half-way around the world. That definitely helps the design. The best flights would probably be those over significant distances that take up a lot of time but would be shorter than halfway across the earth. Which of these flights makes the most sense from an energy and velocity perspective for a spaceplane? Bear in mind the longer the flight the more people would pay a premium for faster speed. Sydney-Los AngelesNew York-MoscowTokyo-SeattleNew York-Sao Paolo Any routes you'd actually recommend for something like this?
I was talking figuratively. "half way around the world" can be substituted with "intercontinental", like the "I" in ICBM.If you want ballistic transport, you're not looking for an airplane - that was what I was trying to say.
My main point was that the intercontinental object shouldn't (IMO!) be an airplane, since the wings are not helping any.
I suspect it will be a 2-stage affair. The first stage core, speculated about on the MCT thread, will double as an electric supersonic jet launcher (think hundreds of people per launch).Intercontinental semi-ballistic travel. Vertical launch, vertical landing.
As has been pointed out on other threads, only long distances make sense at hypersonic speeds since a lot of the overall travel time with flying short flights is just standing around in airport lines waiting to be groped or irradiated.
So...Lifted to altitude by a mothership, which took off from, say... JFK or LAX, detatch & head off for... London Heathrow or somewhere in the Gulf.You're talking about an unpowered, gliding descent, aren't you?
Coming down into quiet airports... no major problem there but the stated intention was to reduce travel time. No way could this vehicle glide into places like London Heathrow or some other major hub airport. You'd have to bump everything else to a holding circle or something while this comes down, surely?
And a rocket-powered plane taking off from JFK or LAX? I don't see it happening.
I think faster air travel is inevitable.It comes down to atmospheric vs suborbital I guess.Using the atmosphere for reaction mass is better but there are aeroheating issues that need to be solved.Is the technology development to make the shapes and materials that can travel through the air at hypersonic speeds without disintegrating cheaper than just building a suborbital spaceplane out of current technologies?
I'm not thinking about small 20 man things either. I don't think there's a business case there. You still need to compete against the planes which means you need to compete on scale.I'm thinking 707 or DC-8 style with 100 passengers + cargo.
Do you go all rocket propulsion like a Lynx?
That might work. I'd say people would feel safer with normal jet engines too but that might not be possible to lug them all the way out of the atmosphere as dead weight.I guess that's where crossover tech like the Skylon SABRE engine comes in.It's ok to add weight if you can get everything back down to the ground and reuse it but you might need small armies for servicing and quality checks. These armies already exist though, they're called aircraft mechanics
Kind of makes me wonder why the Pentagon hasn't looked more into the possibilities of a spaceplane global bomber.
Quote from: Hyperion5 on 11/15/2012 07:06 pm Kind of makes me wonder why the Pentagon hasn't looked more into the possibilities of a spaceplane global bomber. Because it is not needed. It has no advantages over current systems.
I think faster air travel is inevitable.
I guess that's where crossover tech like the Skylon SABRE engine comes in.
Why is it a bad idea to fire rockets at an airport?There's already clearance given to large jets for wake turbulence.