[Spaceships] Can't find the right propulsion system

[Fred Brackin]

Originally Posted by acrosome

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?

If "oms" means Orbital Maneuvering System such as found on the Spece shuttle that _was_ a chemical rocket. In fact it was one using hydrazine and nitrogen tet (storable at room tempeature though hgihly toxic) for fuel. It would ahve had a lower isp than the SSMEs but not an order of magnitude lower.

The OMS were a small pair of engines compared to the SSMEs and you could use a smaller than the normal SM chemical rocket for your workpod. That would cut accelration down to 1 G.

[johndallman]

Originally Posted by Fred Brackin

The OMS were a small pair of engines compared to the SSMEs . . .

They were, in fact, the basic same engine as used in the the Apollo Service Module, which is definitely smaller than the Shuttle. A later version is being used in the Orion spacecraft's service module: good rocket engine designs can stay around a long time.

[Kale]

You can use Smaller Systems to convert a single system into three systems of one size (SM) smaller: You can replace a 3G chemical rocket with a 1G rocket and two small fuel tanks, all one SM smaller than the ship. This gives 2/3rds the capacity of a full SM sized fuel tank. If you want to go really small, you can convert down by two SM levels and get 10 systems at SM-2 for a single full sized slot. Each rocket would provide 0.3G of thrust at that level.

[acrosome]

Originally Posted by Kale

You can use Smaller Systems to convert a single system into three systems of one size (SM) smaller: You can replace a 3G chemical rocket with a 1G rocket and two small fuel tanks, all one SM smaller than the ship. This gives 2/3rds the capacity of a full SM sized fuel tank. If you want to go really small, you can convert down by two SM levels and get 10 systems at SM-2 for a single full sized slot. Each rocket would provide 0.3G of thrust at that level.

This looks like the answer I was seeking.

But, yes, I'm making a lot of little SM+4 pods. But I see no reason I can't still do this. Right?

Yes, initially I designed the pods with antimatter thermal rockets. They were pretty perfect. Except for the spewing radioactive death thing.

Thanks, all.

[Kale]

Originally Posted by acrosome

This looks like the answer I was seeking.
But, yes, I'm making a lot of little SM+4 pods. But I see no reason I can't still do this. Right?

I've actually done this with small "Work Bee" yard ships. They are SM4 and have SM2 smaller systems to represent tiny thrusters and some tools and other equipment. Given that you can make palm-sized chemical rockets, SM2 is still downright large. Here are some fan rules for tiny systems: http://gsuc.roto.nu/doku.php?id=sm_3