## Space combat range bands and thrust

Discuss the Traveller RPG and its many settings
ochd
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### Space combat range bands and thrust

I've been looking at movement in space combat and think I might have been doing it wrong.

According to CRB page 156, it takes 25 points of thrust to move from Very Long range down to Long range or up to Distant range (a distance of, at most, 25,000km).

The way I've been doing it thus far is that if your ship has Thrust 1 that would take you 25 rounds (if you are devoting all the thrust to increasing/decreasing range); thrust 2 would take 13 rounds; thrust 3, 9 rounds; etc. (I'm rounding up.)

However, I then calculated how long a ship with 1G thrust would take to travel 25,000km and found it would only take about 9 combat rounds (assuming constant acceleration to the halfway point, then constant deceleration), or about 7 rounds at constant acceleration.

Which makes me think that actually the thrust required to move range bands needs to be cumulatively added. That would reconcile the difference. So, at 1G constant acceleration it would take 7 rounds (1+2+3+4+5+6+7 = 28); 2G it would take 5 rounds (2+4+6+8+10 = 30); etc.

Does that sound right?

Thanks,

Dan.
phavoc
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### Re: Space combat range bands and thrust

Don't take it literally. The thrust bands are a game mechanic to simplify space combat not on a map. Plus they don't take into account things like velocity at start, angles, etc. It also is not meant to be a 1 for 1 ratio.
AnotherDilbert
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### Re: Space combat range bands and thrust

ochd wrote: I've been looking at movement in space combat and think I might have been doing it wrong.
...
The way I've been doing it thus far is that if your ship has Thrust 1 that would take you 25 rounds (if you are devoting all the thrust to increasing/decreasing range); thrust 2 would take 13 rounds; thrust 3, 9 rounds; etc. (I'm rounding up.)
That is how it is supposed to work.

ochd wrote: However, I then calculated how long a ship with 1G thrust would take to travel 25,000km and found it would only take about 9 combat rounds ...
It's a SIMPLE abstract system. I do not think it tries to be that accurate...

ochd wrote: Which makes me think that actually the thrust required to move range bands needs to be cumulatively added. That would reconcile the difference. So, at 1G constant acceleration it would take 7 rounds (1+2+3+4+5+6+7 = 28); 2G it would take 5 rounds (2+4+6+8+10 = 30); etc.
Yes, that is a one-dimensional vector system (cf CT Starter Traveller, p40). It's more accurate, but also more work to keep track of each crafts vector. I've used it with MgT2 and it works, but not all players like it...

Note that you should keep track of each craft's vector, not just the protagonist's craft's vector.
Condottiere
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### Re: Space combat range bands and thrust

A straight line could be a short life.
ochd
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### Re: Space combat range bands and thrust

AnotherDilbert wrote:
Sun Dec 31, 2017 4:34 pm
That is how it is supposed to work.
Ah, right. Thanks for the clarification. I'll stick with how I was doing it.

... And happy 2018 everyone.

Dan.

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