GURPS Spaceships Design Spreadsheet

[Anthony]

In general, relativistic effects can be ignored as below the resolution of the rules for every reaction drive in spaceships except the total conversion drives and the antimatter pion drives with 15+ fuel modules (where it's making about a 10% difference).

[Agemegos]

Originally Posted by Flyndaran

But since rapidity for 0.200 C is 0.203, I should use (0.200)(0.200/0.203) to get its real cruising speed of 0.197, right?

Yes, that seems about right. It's really not a correction I would bother making in a system in which the mass of empty propellant tanks is ignored.

[Flyndaran]

Originally Posted by Agemegos

Yes, that seems about right. It's really not a correction I would bother making in a system in which the mass of empty propellant tanks is ignored.

Okay, cool. I wasn't sure if it would or not. Thanks.

[Langy]

If relativistic effects are actually important, you can try this out, which will take care of any relativistic effects you may desire.

[Agemegos]

Originally Posted by Langy

If relativistic effects are actually important, you can try this out

It's a link to download an Excel sheet from Dropbox.

I didn't open the Excel file.

[sir_pudding]

Originally Posted by Agemegos

It's a link to download an Excel sheet from Dropbox.

I didn't open the Excel file.

It works for me.

[Flyndaran]

Originally Posted by Langy

If relativistic effects are actually important, you can try this out, which will take care of any relativistic effects you may desire.

That is exactly what I wanted without knowing it existed. Thank you greatly.
Except that the minimum acceleration for the relativistic section is 0.01, when I wanted 0.005 for the AM Pion drive. Probably not enough to screw things up. But it's odd to have such a high minimum.

[vierasmarius]

Originally Posted by Flyndaran

That is exactly what I wanted without knowing it existed. Thank you greatly.
Except that the minimum acceleration for the relativistic section is 0.01, when I wanted 0.005 for the AM Pion drive. Probably not enough to screw things up. But it's odd to have such a high minimum.

That's just the cell formatting. It only displays 2 decimal places, but it's not rounding off in the actual calculation. You can right click to change the cell formatting to display additional digits.

[Flyndaran]

Originally Posted by vierasmarius

That's just the cell formatting. It only displays 2 decimal places, but it's not rounding off in the actual calculation. You can right click to change the cell formatting to display additional digits.

Thanks. I didn't notice that. Can you tell I don't work with spreadsheets outside of gaming?

[Langy]

Originally Posted by Agemegos

It's a link to download an Excel sheet from Dropbox.

I didn't open the Excel file.

Yes, it is. I created it, and it's hosted on my personal Dropbox account. It's free of viruses.

If you want a more complete description, it's an Excel file that calculates travel times, velocities, etc using Spaceships-like statistics (including delta-V requirements for relativistic travel).

EDIT: If it makes you feel better, it has no macros or vB for Applications programming or anything; you should be able to open it and use it in 'safe mode' or whatever it is you call running Excel without allowing it access to the dangerous stuff with no issues.