Heaviest possible SSTO

[kerbiloid]

That's excellent!

[sevenperforce]

12 minutes ago, kerbiloid said:

That's excellent!

I tried translating back into English and got "Enriched with liquid oxygen fortified ether-supercharged nuclear shred" which isn't quite right but sounds cool enough.

I played around with it a bit. German actually has a word for an afterburner fueled by liquid oxygen: Flüssigsauerstoffnachbrenner. And an air intake is a Lufteinlass. And a turbocharger is a Turbolader which just sounds freaking cool. A nuclear rocket engine is an Atomraketenmotor. 

So I suspect the correct term would be Turboladunglufteinlassatomraketenmotor mitflüssigsauerstoffnachbrenner, or "Turbocharged air-intake atomic rocket engine with liquid oxygen afterburner."

 

[Incarnation of Chaos]

9 hours ago, sevenperforce said:

That would get you into reactionless-thruster land. You gotta push against something (planetary magnetic field, atmosphere, etc.) or nothing happens. 

I was actually like 13 or 14 and designed a magnetic "flying saucer" that used gyrostabilizers and a superconducting magnetic repulsor field. The idea was to push against the Earth's magnetic field and hover. When I got a little older, took physics, and did the math, I learned that my idea would have worked...it just would have required exhorbitant amounts of electrical energy. Earth's magnetic field is immense, but very diffuse; levitating any sort of manned flying machine would require creating a magnetic field something like the size of Brazil.

 

To be clear we're assuming that cheap superconductors and fusion power exist. But yeah; you either have to design the ship in a way that it can push against it's self or a planetary field. And that's difficult even conceptually, and you still need rockets to get anywhere even if it works. Nothing like this is going to exist for the foreseeable future.

[Spacescifi]

13 minutes ago, Incarnation of Chaos said:

To be clear we're assuming that cheap superconductors and fusion power exist. But yeah; you either have to design the ship in a way that it can push against it's self or a planetary field. And that's difficult even conceptually, and you still need rockets to get anywhere even if it works. Nothing like this is going to exist for the foreseeable future.

 

In theory you could lift a small vessel powering the electricity for the uber magnetic field with a thousand kilograms of antimatter.

Don't try this at home folks...

[Incarnation of Chaos]

Just now, Spacescifi said:

 

In theory you could lift a small vessel powering the electricity for the uber magnetic field with a thousand kilograms of antimatter.

Don't try this at home folks...

I mean; you're gonna need a penning trap anyway for containment. May as well go full sci-fi and wack it all into something the size of a star destroyer.

[Spacescifi]

46 minutes ago, Incarnation of Chaos said:

I mean; you're gonna need a penning trap anyway for containment. May as well go full sci-fi and wack it all into something the size of a star destroyer.

 

We could only wish for that now. We have trouble keeping nuclear powered rocketry cool. Oh we know how, but that adds weight, and as you know... weight is the giant obstacle of getting heavy stuff into space no matter how you choose to do it.

The heavier you make the ship, the more antimatter you will need to harness at any given moment to power the uber magnetic field. Which also requires more mass/weight for cooling than you would need otherwise.

Basically, all of this seems cumulative. I am not saying this is a show stopper, but it does seem really, really hard.

Harder than rocketry, since at least with rocketry mass shed is traded for speed.

Here we are basically converting kilograms of antimatter into uber magnetic fields... and I am not sure this has zero losses to heat, thus the required cooling equipment.

[Incarnation of Chaos]

3 hours ago, Spacescifi said:

 

We could only wish for that now. We have trouble keeping nuclear powered rocketry cool. Oh we know how, but that adds weight, and as you know... weight is the giant obstacle of getting heavy stuff into space no matter how you choose to do it.

The heavier you make the ship, the more antimatter you will need to harness at any given moment to power the uber magnetic field. Which also requires more mass/weight for cooling than you would need otherwise.

Basically, all of this seems cumulative. I am not saying this is a show stopper, but it does seem really, really hard.

Harder than rocketry, since at least with rocketry mass shed is traded for speed.

Here we are basically converting kilograms of antimatter into uber magnetic fields... and I am not sure this has zero losses to heat, thus the required cooling equipment.

Well i'm only thinking of using Antimatter for propulsion; fusion would be providing power as it scales up pretty well. But yes; it's all cumulative. And heat transport would be an issue; but graphene radiators could be pretty epic.

[Spacescifi]

4 hours ago, Incarnation of Chaos said:

Well i'm only thinking of using Antimatter for propulsion; fusion would be providing power as it scales up pretty well. But yes; it's all cumulative. And heat transport would be an issue; but graphene radiators could be pretty epic.

 

Fusion is near impossible to implement for nearly the same reasons antimatter is.

Storage. Stars cause fusion in their cores with a star's worth of mass and pressure and heat to cause fusion. We do not have that. Current schemes use magnetic fielda to hold the plasma, which tends to slip out on a regular basis, hitting the chamber walls which causes the plasma to cool and kills the temperature required for a sustained reaction.

So in short, you need a high temperature (often higher than the core of the sun) snd magnetic fields that won't leak out plasma.

 

[Incarnation of Chaos]

7 minutes ago, Spacescifi said:

 

Fusion is near impossible to implement for nearly the same reasons antimatter is.

Storage. Stars cause fusion in their cores with a star's worth of mass and pressure and heat to cause fusion. We do not have that. Current schemes use magnetic fielda to hold the plasma, which tends to slip out on a regular basis, hitting the chamber walls which causes the plasma to cool and kills the temperature required for a sustained reaction.

So in short, you need a high temperature (often higher than the core of the sun) snd magnetic fields that won't leak out plasma.

 

Which after 60 years we're fairly close to perfecting; by the time you're playing with Antimatter you're going to have ICF in the bag.

[DDE]

20 hours ago, sevenperforce said:

Mitflüssigemsauerstoffangereichertethermischaufgeladenekernramrakete.

Das ist ein bisschen zu kurz.

[sevenperforce]

14 hours ago, Incarnation of Chaos said:

To be clear we're assuming that cheap superconductors and fusion power exist. But yeah; you either have to design the ship in a way that it can push against it's self...

Pushing against itself will not happen.

14 hours ago, Incarnation of Chaos said:

...or a planetary field. And that's difficult even conceptually, and you still need rockets to get anywhere even if it works. Nothing like this is going to exist for the foreseeable future.

Too bad there is no such thing as a "gravity brake" or some other way to interact with gravitational field lines and not constantly expend energy.

9 hours ago, Incarnation of Chaos said:

13 hours ago, Spacescifi said:

Here we are basically converting kilograms of antimatter into uber magnetic fields... and I am not sure this has zero losses to heat, thus the required cooling equipment.

Well i'm only thinking of using Antimatter for propulsion; fusion would be providing power as it scales up pretty well. But yes; it's all cumulative. And heat transport would be an issue; but graphene radiators could be pretty epic.

Antimatter-catalyzed nuclear pulse propulsion is a good intermediate step and could scale Orion down to pulsejet size, which would make for one hell of a spectacular upgrade to Project Pluto.

In the nearer term, z-pinch fusion pulse propulsion is an even easier (and clean-burning) alternative. It can be scaled quite small. Ordinarily it needs a magnetic nozzle but I wonder if it could be used in-atmosphere with a turboladunglufteinlassraketenmotor. At liftoff you'd be using lithium fusion to heat an airflow as working mass; as you accelerated you'd switch from airflow-only to a hydrogen or even methane working fluid, and then once orbital you could turn on the magnetic nozzle and do your Earth escape burn at 19,400 s.

[Incarnation of Chaos]

14 hours ago, sevenperforce said:

Pushing against itself will not happen.

Too bad there is no such thing as a "gravity brake" or some other way to interact with gravitational field lines and not constantly expend energy.

Antimatter-catalyzed nuclear pulse propulsion is a good intermediate step and could scale Orion down to pulsejet size, which would make for one hell of a spectacular upgrade to Project Pluto.

In the nearer term, z-pinch fusion pulse propulsion is an even easier (and clean-burning) alternative. It can be scaled quite small. Ordinarily it needs a magnetic nozzle but I wonder if it could be used in-atmosphere with a turboladunglufteinlassraketenmotor. At liftoff you'd be using lithium fusion to heat an airflow as working mass; as you accelerated you'd switch from airflow-only to a hydrogen or even methane working fluid, and then once orbital you could turn on the magnetic nozzle and do your Earth escape burn at 19,400 s.

It's not that i don't believe you, but why couldn't a ship be built in a way that the field lines could push against bottom and provide some lift?

[Spacescifi]

6 minutes ago, Incarnation of Chaos said:

It's not that i don't believe you, but why couldn't a ship be built in a way that the field lines could push against bottom and provide some lift?

 

Gravity. Unless there is a way to do it I am unaware of, the method we use thus far to beat gravity requires either throwing mass or energy away. Rocketry.

What you are proposing I tend to view through the rocket lens. Thinking it needs some external medium to push against if it is'nt throwing anything out (a car pushes it's wheels against the road).

Forces tend to balance each other out, and something must be used or expelled to get anywhere.

Otherwise forces balance out and all is static.

To push a magnet upward with itself sounds... not possible. As far as I am aware, some external reacting medium is required for any motion that is not rocket derived.

Edited September 21, 2019 by Spacescifi

[Incarnation of Chaos]

Just now, Spacescifi said:

 

Gravity. Unless there is a way to do it I am unaware of, the method we use thus far to beat gravity requires either throwing mass or energy away. Rocketry.

What you are proposing I tend to view through the rocket lens. Thinking it needs some external medium to push against if it is'nt throwing anything out.

Forces tend to balance each other out, and something must be used or expelled to get anywhere.

Otherwise forces balance out and all is 

Please note that cancellation is the exact goal here; with the magnetic field only providing enough force to repel the ship or earth. You are not propelling the ship with it; your using it to lift it to where you can use the propulsion you have. 

[sevenperforce]

10 hours ago, Incarnation of Chaos said:

It's not that i don't believe you, but why couldn't a ship be built in a way that the field lines could push against bottom and provide some lift?

Magnetic field lines or gravitational field lines?

Magnetic field lines can absolutely be used to "push" against. That's how a magnetic tether works.

Gravitational field lines are just a force gradient. They cannot be "pushed" against.

A ship cannot push against itself. It's like trying to pick yourself up by pulling on your own suspenders.

[Incarnation of Chaos]

9 hours ago, sevenperforce said:

Magnetic field lines or gravitational field lines?

Magnetic field lines can absolutely be used to "push" against. That's how a magnetic tether works.

Gravitational field lines are just a force gradient. They cannot be "pushed" against.

A ship cannot push against itself. It's like trying to pick yourself up by pulling on your own suspenders.

Magnetic; if you could control gravity then why bother with any of these things since you could just null out your mass. But blue space magic hasn't been discovered yet xD

Also all rockets technically push themselves when in space.