Airship-to-Orbit?

Can an airship travel to orbit?

I was surfing at www.jpaerospace.com and they say it can be done. They have a nice little presentation on PDF that gives a detailed explanation.

Is it possible that the oldest aerial technology can also be the first to take the masses to space?

NO! An airship requires atmosphere to give ir buoyancy

I think their idea is to use aerodynamic lift to take the airship to 200,000 feet.

At which point an ion drive will accelerate it to orbital velocity.

I'll look again when it's working, but it's kinda novel (at least to me).

Nice idea, but:

1) They want to build a 6,000 foot long airship using a construction facility permanently parked at 140,000 feet up. Might be a little tough. They are probably right in their calculations that it would take an airship of this size to reach 200,000 feet.

2) They want to use a solar powered electric motor with a propeller over a period of five days to accelerate the big airship to orbital velocity at 200,000 feet. Aside from the problems of using a big paddle bladed propeller to reach supersonic speeds, one might ponder the problem of how much drag a 6,000 foot long airship is going to produce. I suspect that the electric motor will not be able to accelerate the airship to anything near orbital velocity.

3) But then they want to cruise about the solar system using this same electric motor for propulsion. For this, the airship must achieve not only orbital velocity, but escape velocity. It would be especially interesting to see how they get a propeller to work in the vacuum of space.

I suspect that the Prop is only to get to the 140Kft Dark sky Station. The big gas bag uses solar powered Ion thrustors to get to orbit. Much better specific impulse than traditional rockets.

The Space nuts at sci.space.tech seem to think that if the air is dense enough for lift/ boyancy then it is too dense to go fast enough to get to orbital velocity. The general consensus is that it takes 'impossibly' efficent aerodynamics at an unbelieveibly huge scale.

Very Very cool idea if it works.

On Mon, 24 May 2004 20:15:34 -0700, 'C J Campbell'

When I read the article, what I saw was that they wanted to glide the airship upwards and have it accelerate as it rose, using the positive buoyancy as it's source of thrust. So it'd be an upside-down glider. They were proposing to gain much of the airship's escape velocity that way.

My understanding is that when they mean electric propulsion, they're not talking about an electric motor. They mean an electric ion-thruster, which expels charged ions straight out at very high velocity. Electric ion-thrusters are supposed to be 5 times as efficient as chemical combustion rocket engines, propellant-wise, and they are powered by electricity which a blimp could gather thru solar energy. But they need to operate in a vacuum or near-vacuum environment, which is why it might make sense with an airship that is up where the air is very thin. The problem is that the thrust from an ion-engine is very low, like a small puff from your lungs, so it can't really move a big object like a blimp. But ion-engines are very long-lasting (can operate for tens of thousands of hours before wearing out) compared to chemical rocket engines. But who wants to take so long to get to orbit???

There are other types of electric thrusters which can produce more thrust, such as the VASIMR, they'd need megawatts of power like from a nuclear reactor. Could the surface area of a blimp gather that much solar energy?

The pictures look fake to me. I also get real leary when they ask for donations.