suggestion : Arcjet rocket

[Sereneti]

https://en.wikipedia.org/wiki/Arcjet_rocket
 

thats an existing engine

that sounds good ,

 

[Wjolcz]

That's pretty cool actually.

[Sereneti]

Implement like:
higher ISP than the nerv engine , but smaller trust
Use Monopropelant or liquid fuel
Is posible to use as an RCS
Is posible to use as an engine

 

[Nich]

585 isp would translate to about 450 isp in the kerbal universe.  And it would have bad TWR and electrical requirements.  I dont think I would ever use it once I have Nuke and Ion unlocked.  

[11of10]

You actually have one in one of Roverdude's mods, not sure which one tho. Works on monoprop, has 585s ISP, and uses power. Also, another one, 1300s ISP, and a power hog. 

[spacebrick3]

3 hours ago, 11of10 said:

You actually have one in one of Roverdude's mods, not sure which one tho. Works on monoprop, has 585s ISP, and uses power. Also, another one, 1300s ISP, and a power hog. 

I think it's RLA Stockalike.

I also think this would be a good "early game" engine, if it had decent thrust to make interplanetary transfers viable without chemical rockets before the NERVA and Dawn.

[Wyzard]

This would be a good complement to the existing nuclear and ion engines.  The Dawn is only really useful for very small spacecraft due to its low thrust, and the LV-N is big enough and heavy enough that it's best suited to large spacecraft.  A monoprop/electrical hybrid, with size and mass roughly on par with the Terrier or the aerospike engine, electrical requirements roughly on par with the Dawn, and ISP roughly on par with the LV-N, would be a good fit for mid-sized spacecraft.

[cantab]

Yeah, I think it could have a niche. To me most obvious would be one based on the MR-510 that acts as an RCS thruster and runs on monopropellant - double the efficiency of regular RCS, but you need to keep it powered. A comparison with existing engines is also warranted now RCS thrusters have a "respond to throttle" option; compared to the Dawn ion engine the arcjet would require significantly less power, maybe one or two RTGs would suffice, and be a lot lighter and more compact.

It's not such an obvious technology for a larger engine, though I suppose it could be done, if only for completeness.

[DDE]

Uh... they don't have to be powered. From what I understand it's possible to "arc-boost" a regular monoprop thruster.