Rocket engines - from speculations to successful flights

[lpetrich]

 Spacecraft propulsion is a nice article on that subject. Toward the end is a table of methods from speculations to successfully-used systems. It uses NASA's version of  Technology readiness level:

1. Basic principles observed and reported
2. Technology concept and/or application formulated
3. Analytical and experimental critical function and/or characteristic proof of concept
4. Component and/or breadboard validation in laboratory environment
5. Component and/or breadboard validation in relevant environment
6. System/subsystem model or prototype demonstration in a relevant environment (ground or space)
7. System prototype demonstration in a space environment
8. Actual system completed and 'flight qualified' through test and demonstration (ground or space)
9. Actual system 'flight proven' through successful mission operations

Some kinds of rocket engines with their readiness ratings:

• Chemical: #9
• Ion: #9
• Mass-driver (linear-motor gun): #6
• Nuclear thermal: #6
• Magnetoplasma: #5 - #6
• Nuclear electric: #4
• Orion nuclear-bomb pulse engine: #3
• Daedalus inertial-confinement-fusion pulse engine, other exotic nuclear engines: #2
• Bussard ramjet: #2

Then a sizable list of very speculative sorts of rocket engines, from photon engines to faster-than-light ones.

 

[barbos]

What about EM-drive?

 

[lpetrich]

What about EM-drive?

Over in Wikipedia, "EM drive" redirects to  RF resonant cavity thruster

I am totally skeptical about that. it does not seem to be reliable, and I agree with some other skeptics about it that positive results are likely to be experimental errors.

 

[Worldtraveller]

Rumor at one point was that NASA was going to try one in a micro-gravity requirement. Not sure if they are planning to go forward with it.

Even if don't understand it, if it offers better efficiency than ion, then I say we test it and get it going, and figure it out later.

 

[barbos]

What about EM-drive?

Over in Wikipedia, "EM drive" redirects to  RF resonant cavity thruster

I am totally skeptical about that. it does not seem to be reliable, and I agree with some other skeptics about it that positive results are likely to be experimental errors.

Of course it is a total BS, I was trying to make fun of NASA "rocket scientists" who are unaware of such a thing as experimental errors.

 

[Loren Pechtel]

Bussard ramjet? I thought that was effectively impossible due to the energy lost dragging the stuff in and accelerating it to your spacecraft's speed.

 

[untermensche]

These missiles or some future generation are likely going to end life as we know it someday.

Isn't it great we invented them?

 

[Treedbear]

These missiles or some future generation are likely going to end life as we know it someday.

Isn't it great we invented them?

Or it might be that humans are the first species capable of deflecting an asteroid that would have caused another mass extinction. It might be the main thing that really makes us truly unique (next to blue-green algae that is).

 

[James Brown]

What about other means of propulsion like magsails and solar sails? Are those outside the scope of this thread?

 

[lpetrich]

What about other means of propulsion like magsails and solar sails? Are those outside the scope of this thread?

Feel free to talk about them here. They are for spacecraft propulsion, along with other non-rockets like tethers and space elevators.

Solar sails:
9: Light pressure attitude-control flight proven
6: Deploy-only demonstrated in space
5: Light-sail validated in medium vacuum

Electric and magnetic sails: 3: Validated proof-of-concept
These work by interacting with the solar wind.

 

[Loren Pechtel]

These missiles or some future generation are likely going to end life as we know it someday.

Isn't it great we invented them?

Missiles? Most of those drives can only be used in space and are slow enough not to be of much use in warfare.

Some of them, however, could be very useful in deflecting the next dinosaur killer.

 

[untermensche]

These missiles or some future generation are likely going to end life as we know it someday.

Isn't it great we invented them?

Missiles? Most of those drives can only be used in space and are slow enough not to be of much use in warfare.

Some of them, however, could be very useful in deflecting the next dinosaur killer.

The odds are astronomically higher they will be used to end the human race than save it.

 

[skepticalbip]

These missiles or some future generation are likely going to end life as we know it someday.

Isn't it great we invented them?

Missiles? Most of those drives can only be used in space and are slow enough not to be of much use in warfare.

Some of them, however, could be very useful in deflecting the next dinosaur killer.

The odds are astronomically higher they will be used to end the human race than save it.

You seem to have confused rocket engines for missiles. Now you seem to be confusing missiles for nuclear warheads, very different things.

 

[untermensche]

The odds are astronomically higher they will be used to end the human race than save it.

You seem to have confused rocket engines for missiles. Now you seem to be confusing missiles for nuclear warheads, very different things.

I'm not confusing anything.

The technology to send missiles into space is the technology that will likely end humanity and prove intelligence is a lethal mutation.

 

[skepticalbip]

The odds are astronomically higher they will be used to end the human race than save it.

You seem to have confused rocket engines for missiles. Now you seem to be confusing missiles for nuclear warheads, very different things.

I'm not confusing anything.

The technology to send missiles into space is the technology that will likely end humanity and prove intelligence is a lethal mutation.

Silly "reasoning". It could as reasonably be argued that humans learning to control fire will likely cause the end humanity so we should, for the sake of humanity, abandon fire and not pass on our knowledge of it to our offspring.

 

[untermensche]

I'm not confusing anything.

The technology to send missiles into space is the technology that will likely end humanity and prove intelligence is a lethal mutation.

Silly "reasoning". It could as reasonably be argued that humans learning to control fire will likely cause the end humanity so we should, for the sake of humanity, abandon fire and not pass on our knowledge of it to our offspring.

The waging of war until we reach the state where nuclear weapons can be launched into space is not a necessary result of learning to build a fire.

Humans willingly following other humans to war is the root cause of it, human mass passivity to authority is the cause of it, but saying it is inevitable just because of the domestication of fire is absurd.

 

[skepticalbip]

I'm not confusing anything.

The technology to send missiles into space is the technology that will likely end humanity and prove intelligence is a lethal mutation.

Silly "reasoning". It could as reasonably be argued that humans learning to control fire will likely cause the end humanity so we should, for the sake of humanity, abandon fire and not pass on our knowledge of it to our offspring.

The waging of war until we reach the state where nuclear weapons can be launched into space is not a necessary result of learning to build a fire.

Control of fire is certainly necessary (though not sufficient) for the advancement of technology. There could be no smelting of metals or even creation of ceramic pottery without it. Without metals, no technology using metals could be possible. If you are advocating a world without technology then elimination of fire would insure that.

Humans willingly following other humans to war is the root cause of it, human mass passivity to authority is the cause of it, but saying it is inevitable just because of the domestication of fire is absurd.

Then your complaint is with human nature, not rockets. Humans had war in the paleolithic. But without fire there would be no rockets, guns, or even swords.

 

[Loren Pechtel]

These missiles or some future generation are likely going to end life as we know it someday.

Isn't it great we invented them?

Missiles? Most of those drives can only be used in space and are slow enough not to be of much use in warfare.

Some of them, however, could be very useful in deflecting the next dinosaur killer.

The odds are astronomically higher they will be used to end the human race than save it.

How is a low-acceleration deep-space missile an issue? Such things are far easier to shoot down than launch.

 

[Loren Pechtel]

The odds are astronomically higher they will be used to end the human race than save it.

You seem to have confused rocket engines for missiles. Now you seem to be confusing missiles for nuclear warheads, very different things.

I think he's taking the usual far left big-tech-is-evil. Never mind that that's a prescription for the destruction of the human race.

 

[untermensche]

The odds are astronomically higher they will be used to end the human race than save it.

You seem to have confused rocket engines for missiles. Now you seem to be confusing missiles for nuclear warheads, very different things.

I think he's taking the usual far left big-tech-is-evil. Never mind that that's a prescription for the destruction of the human race.

You are very stupid if you think that.

Missile technology has endangered all of humanity.

We are much less safe because we have them.

Especially when morons elect people like Trump.