Escape Dynamics tested 100 kw microwave system and produced thrust,the goal is Single stage to orbit reusable launch.

"A small Colorado company has successfully tested a new type of propulsion
technology that it believes could eventually enable low-cost, single-stage-to-
orbit launch vehicles.

Broomfield, Colorado-based Escape Dynamics announced July 17 it carried out a
small-scale test in the laboratory of its beamed microwave thruster. In that
test, the company beamed microwave energy to a thruster, heating helium
propellant and generating a small amount of thrust."


"EDI's external propulsion launch system will operate at a specific impulse
above 750 seconds and this breakthrough increase in efficiency reduces the
fraction of mass dedicated to propellant to less than 72%. The increase of 3x
in the mass fraction dedicated to structure and payload for the first time
opens doors for reusability and single-stage-to-orbit flight."

See:

http://nextbigfuture.com/2015/08/esc...microwave.html

In article ,
says...

"A small Colorado company has successfully tested a new type of propulsion
technology that it believes could eventually enable low-cost, single-stage-to-
orbit launch vehicles.

Broomfield, Colorado-based Escape Dynamics announced July 17 it carried out a
small-scale test in the laboratory of its beamed microwave thruster. In that
test, the company beamed microwave energy to a thruster, heating helium
propellant and generating a small amount of thrust."


"EDI's external propulsion launch system will operate at a specific impulse
above 750 seconds and this breakthrough increase in efficiency reduces the
fraction of mass dedicated to propellant to less than 72%. The increase of 3x
in the mass fraction dedicated to structure and payload for the first time
opens doors for reusability and single-stage-to-orbit flight."

See:

http://nextbigfuture.com/2015/08/esc...microwave.html

Because we all know in our performance uber alles hearts that launch
costs scale with dry mass fraction. :-P

I have a feeling the big fracking microwave antennas needed to make this
work might cost a wee bit more than a launch pad for a conventional
launch vehicle. That and the efficiency is going to drop off with
distance and adverse atmospheric conditions (weather), so for routine
launch to LEO, I'm not sure you're going to save any money over a
reusable LOX/kerosene TSTO.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

Le 8/5/15 7:31 PM, Jeff Findley a écrit :
In article ,
says...

"A small Colorado company has successfully tested a new type of propulsion
technology that it believes could eventually enable low-cost, single-stage-to-
orbit launch vehicles.

Broomfield, Colorado-based Escape Dynamics announced July 17 it carried out a
small-scale test in the laboratory of its beamed microwave thruster. In that
test, the company beamed microwave energy to a thruster, heating helium
propellant and generating a small amount of thrust."


"EDI's external propulsion launch system will operate at a specific impulse
above 750 seconds and this breakthrough increase in efficiency reduces the
fraction of mass dedicated to propellant to less than 72%. The increase of 3x
in the mass fraction dedicated to structure and payload for the first time
opens doors for reusability and single-stage-to-orbit flight."

See:

http://nextbigfuture.com/2015/08/esc...microwave.html

Because we all know in our performance uber alles hearts that launch
costs scale with dry mass fraction. :-P

I have a feeling the big fracking microwave antennas needed to make this
work might cost a wee bit more than a launch pad for a conventional
launch vehicle. That and the efficiency is going to drop off with
distance and adverse atmospheric conditions (weather), so for routine
launch to LEO, I'm not sure you're going to save any money over a
reusable LOX/kerosene TSTO.

Not to mention that the 3x increase in mass fraction is quite small
compared to the increase in propellant cost. LOX/kerosene is very cheap
compared to He. Nonetheless, it's cool to see new technologies being
developed, even if they aren't practical.


Alain Fournier