Creating a new THS space drive

[the-red-scare]

Originally Posted by mindbound

What is the 0.1 in the calculation, how does the 0.005 factor in there, and how do you get 0.4 from 0.1*4/0.05? I assume I have misunderstood the formula there.

The 0.1 is a mistake! Should be 0.005 because that’s the Gs I specified. I rewrote the example and that got left in by mistake. Fixing it now above.

Originally Posted by mindbound

Do I understand it correctly that by multiplying the TWR by 4 (presumably the mass per space of drive?) I'll get the THS' thrust per space of drive figure?

Yep, T/W is unitless, so multiplying by any weight gives you the thrust for an engine of that weight. All THS drives are 4 tons per space, so multiplying 4 by the T/W is the tons of thrust.

[the-red-scare]

Here’s an example from Atomic Rockets. All I’m using is the info from the Engine List.

ACMF (Antimatter-Catalyzed Micro-Fission/Fusion)
Thrust: 2.7
Mass: 4
Cost: 0.8
Output: 0
Power: 0
RMC: 0.005N
ISP: 13,500

Thrust is 4 * 0.680
F is 24,030
Ve is 132,300
Flow rate is 0.0154 kg/s
Or 0.061 tons/hour
RMC is 0.061/12

All pulse drives use generic “nuclear pellets” which are 12 tons per space and we don’t really have anything better to base density on. But as you can see, pretty easy!

[mindbound]

Originally Posted by the-red-scare

The 0.1 is a mistake! Should be 0.005 because that’s the Gs I specified. I rewrote the example and that got left in by mistake. Fixing it now above.

Yep, T/W is unitless, so multiplying by any weight gives you the thrust for an engine of that weight. All THS drives are 4 tons per space, so multiplying 4 by the T/W is the tons of thrust.

Makes sense, I was just checking if I hadn't accidentally misunderstood any of your points. Thanks for the correction w.r.t. the G numbers!