Replies

I really like the idea of building an air breathing airplane that has a kerosene/LOX engine in the tail. Takes off on a runway with a cargo of LOX and a bit of JP4. Hit's a tanker just like a regular F-18 at alititude and gets enough JP4 to feed the rocket up to mach 10 or so. Climbs to around 300k feet, and dumps out an upper stage during its 45 seconds in space.

Fly it every day for the cost of an international 747 flight.

Don't spend much money on the orbital hardware. After all, if it fails, just send up another one.

Space flight can be so cheap, if it just wasn't for the government.

really like the idea of building an air breathing airplane that has a kerosene/LOX engine in the tail. Takes off on a runway with a cargo of LOX and a bit of JP4. Hit's a tanker just like a regular F-18 at alititude and gets enough JP4 to feed the rocket up to mach 10 or so. Climbs to around 300k feet, and dumps out an upper stage during its 45 seconds in

While a luadable goal, this is years off and in any event it will be used for humans and smallish cargo. We will need something near term and this is a good alternative.

We need to safe human transportation now and thus need to separate cargo and human launchings.

I really like the idea of building an air breathing airplane that has a kerosene/LOX engine in the tail.

One problem with that is that there is a serious shortage of LOX/Kero engines that are reusable more than a dozen times. The closest I know of is the Russian RD-0124, which only gets 30 tons of thrust and might have some trouble operating at an altitude under 100,000 feet. Another problem is the heating that occur while flying at over Mach 4, even at such high altitude. Meeting a tanker aircraft would most likely double the cost.

Airlaunch is a very good idea, but it is not at all clear that the slight benefits of a supersonic release would outweigh its technical problems.

Pratt and Whitney claims to have developed an extremely reusable LOX/LH2 engine ideally sized for a airlaunch assisted SSTO. A 100 ton GLOW rocket using that engine could place about 15 tons in orbit, three to five tons of which could be payload, depending on the design of the re-entry/landing system.

Operational costs of a fully reusable airlaunched SSTO could be under $100/lb delivered to LEO. It would probably make sense to fly from an airport close to the coast near the equator, but in theory you could fly from anywhere.

Even if we had a reliable system like this, I believe it would still be a good idea to develop a genuine heavy-lift capability. I do not think that a revised Shuttle-C is the right idea. Giant shipyard-built, pressure-fed, multi-stage big dumb boosters could be boosting 300-500 ton payloads into orbit within three years, if a $2 billion development project were started now, IMO.

20 - "I really like the idea of building an air breathing airplane that has a kerosene/LOX engine in the tail. Takes off on a runway with a cargo of LOX and a bit of JP4. Hit's a tanker just like a regular F-18 at alititude and gets enough JP4 to feed the rocket up to mach 10 or so. Climbs to around 300k feet, and dumps out an upper stage during its 45 seconds in space."

Interesting concept - seems like it should have been explored already.

Ah, I know - too simple. Too sensible.

In fact, isn't that basically exactly what our plastic plane builder going to do out of his own pocket?