[Spaceships] Real Life Non-Super Science Reactionless Engines

[scc]

From this news article: http://www.wired.co.uk/news/archive/...le-space-drive

For those who don't want to read it, there is are reproducible proof that specific microwaves inside a closed vessel will produce thrust.

Based upon statements in the article about using it on satellites I'd give it the same thrust as an Ion Drive system. TL would be 9, but we COULD make microwaves as far back as WW2, so it could possibly be built earlier then that

[Agemegos]

This FAQ by the inventor is interesting.

Note however, because the EmDrive obeys the law of conservation of energy, this thrust/power ratio rapidly decreases if the EmDrive is used to accelerate the vehicle along the thrust vector. (See Equation 16 of the theory paper). Whilst the EmDrive can provide lift to counter gravity, (and is therefore not losing kinetic energy), auxiliary propulsion is required to provide the kinetic energy to accelerate the vehicle.

Emphasis added

It'll bear a static load, but not accelerate a vehicle. So it's a sort of suspension, not a drive.

Still amazing, though. 30 Newtons per Watt is astounding.

[malloyd]

Originally Posted by Agemegos

Still amazing, though. 30 Newtons per Watt is astounding.

30 Newtons per watt is outright ridiculous - that ought to be pushing your test pendulum into the wall of your test chamber. 30 micronewtons per watt, which is closer to what's been claimed in the prior press releases for this stuff (note that it's not new, and it's always been press releases and not actual peer reviewed papers, which pretty well ought to tell you there is nothing here) is much more in keeping with some sort of ion wind effect.

[Agemegos]

Originally Posted by malloyd

30 Newtons per watt is outright ridiculous - that ought to be pushing your test pendulum into the wall of your test chamber. 30 micronewtons per watt, which is closer to what's been claimed in the prior press releases for this stuff (note that it's not new, and it's always been press releases and not actual peer reviewed papers, which pretty well ought to tell you there is nothing here) is much more in keeping with some sort of ion wind effect.

Exactly so.

Separately, a thruster that ceases to produce thrust as its thrust produces acceleration is nonsense.

[malloyd]

Originally Posted by Agemegos

Exactly so.

Separately, a thruster that ceases to produce thrust as its thrust produces acceleration is nonsense.

Just to clarify that a little, at 30 N/W, space drives are not your market, you need to talk to outboard motor manufacturers instead. This beats the performance of the marine engines by a factor of about 100.

[Agemegos]

The people you need to talk to are the aviation industry. The device described in the FAQ replaces wings, including rotors.

[RogerBW]

Originally Posted by malloyd

Just to clarify that a little, at 30 N/W, space drives are not your market, you need to talk to outboard motor manufacturers instead. This beats the performance of the marine engines by a factor of about 100.

Feed my 110kW car engine's output through a 30N/W converter and it'll accelerate said car at over 2,000 gravities. That makes every other form of transport obsolete.

[Anthony]

Incidentally, the 'theory' behind the EmDrive is actually reliant on inability to do basic geometry, as it's a container where somehow internal radiation pressure produces unbalanced effects...

[Anthony]

Originally Posted by scc

From this news article: http://www.wired.co.uk/news/archive/...le-space-drive

For those who don't want to read it, there is are reproducible proof that specific microwaves inside a closed vessel will produce thrust.

The described setup does not actually prove anything.

Originally Posted by http://ntrs.nasa.gov/search.jsp?R=20140006052

....
within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure
....
Thrust was observed on both test articles, even though one of the test articles was designed with the expectation that it would not produce thrust.

Both of those things are fatal errors. They're getting the appearance of thrust from bad setup, not any real effect.

[vicky_molokh]

Originally Posted by Anthony

Both of those things are fatal errors. They're getting the appearance of thrust from bad setup, not any real effect.

Having that from NASA seems weird. Genuinely bad experiment control by NASA, or just a badly-written article?