[Spaceships] Can't find the right propulsion system

[Anthony]

I would avoid HEDM if not needed, seeing as it tends to be explosive. Systems with low delta-V requirements are typically willing to trade performance for safety.

[AlexanderHowl]

Originally Posted by Anthony

I would avoid HEDM if not needed, seeing as it tends to be explosive. Systems with low delta-V requirements are typically willing to trade performance for safety.

Antimatter also tends to explode, and it seems to be ubiquitous in the setting. If you do not want HEDM, you can do chemical rockets for 1g and 0.1 mps.

[Johnny1A.2]

Originally Posted by acrosome

Hi, all. I'm trying to find an appropriate propulsion system for little work pods and inter-ship lighters, for in the space near stations, in work areas, etc. These are not long-range vehicles so they don't need massive delta-V. But they probably do need acceleration measured in something larger than milligees, if only for time management concerns, so Ion and VASMIR drives are out.

In this setting (TL10) there is a limited superscience switch that makes antimatter extremely cheap and things like the antimatter plasma torch possible. But for small craft like this such systems wouldn't be used since every Tom, Dick, and Harry welder or taxi pilot can't be trusted with a drive that spews radioactive death.

So for the life of me the only option I seem to be able to find is a chemical rocket. But this seems like overkill at 3G acceleration. What I really need is just some sort of OMS, y'know? Have I missed some other option?

For the mission you describe, 3G sounds like more acceleration than you'd likely want anyway. Why do work pods and intership taxi vehicles need that kind of acceleration?

[Say, it isn't that bad!]

Where are the rules for using smaller systems on larger craft?

[Ulzgoroth]

Originally Posted by Say, it isn't that bad!

Where are the rules for using smaller systems on larger craft?

Spaceships 7, p4-5.

Also, if you have guesses about how it works, they're probably right. It's not very complicated or tricky.

[acrosome]

Originally Posted by Johnny1A.2

For the mission you describe, 3G sounds like more acceleration than you'd likely want anyway. Why do work pods and intership taxi vehicles need that kind of acceleration?

Because they don't; you failed your Reading check. :) I said that 3G rockets were overkill. You're thinking that I said the exact opposite of what I actually said.

Originally Posted by Ulzgoroth

Spaceships 7, p4-5.

Also, if you have guesses about how it works, they're probably right. It's not very complicated or tricky.

Thank you.

[Kale]

I find the 3G rocket systems are handy for Tug designs that might end up having to clamp to and move a larger vessel. For small ships that just have to go to a nearby location in a shipyard though, an SM-2 system at 0.3G is plenty. Just remember if you need to drag around a big hull plate or something the extra mass might actually justify the full 3G. For instance an SM5 tug can shove around an SM6 ship at 0.75G if the tug has a full 3G rocket system installed. Just make sure not to use the rocket at full thrust when the tug isn't actually pulling anything.

[AlexanderHowl]

I would honestly go with a higher delta-v system. A nuclear thermal rocket provides 0.5g and 0.45 mps per fuel tanks at TL9+. It could even be used for shuttle taxis from the surface to orbit and back.

[Anthony]

Originally Posted by AlexanderHowl

I would honestly go with a higher delta-v system. A nuclear thermal rocket provides 0.5g and 0.45 mps per fuel tanks at TL9+. It could even be used for shuttle taxis from the surface to orbit and back.

In general the more delta-V per tank, the more destructive the exhaust. Depending on the details of how it's to be used, it might be better to not use a reaction drive at all (use something like tethers, or something that interacts with EM fields created by a larger vehicle).