Re: GURPS Spaceships Design Spreadsheet
 

Hi Eric.
Amazing Sheet (wish I could generate something this nice.)
A quick question. Why did you make the fuel tanks content (i.e. water, hydrogen etc) as a separate system?
imho it would be better to have just 1 fuel tank system and define it's content via the spaceship options (where you define high thrust for an engine)

Adi

Re: GURPS Spaceships Design Spreadsheet
 

I can't answer for Eric, but I assume this is so you can easily have a ship with multiple fuel types. For example, it might have Chemical Rockets to boost to orbit, but use a Vasimir Ion Engine for space flight. You could separate this off into the spaceships options, and I suppose that would save space in the systems list. But it would also mean that you'd need to go searching for the fuel types if you want to change them.

Re: GURPS Spaceships Design Spreadsheet
 

Thank you.

You must realize that this sheet is the result of several hundred hours work over several years and has progressed through slow evolutions. The answer to this one, quite simply, is because it never occurred to me to change it to use the Options menus. I may consider changing it for the next version, especially since this should be a relatively easy change, as things go.

Re: GURPS Spaceships Design Spreadsheet
 

Version 2.0 Release Candidate 4

-Folded Fuel Tank contents into Options 1 menu rather than listing all Fuel Tank contents as separate systems
-Many other minor bug fixes.

Excel 2000
http://gurpsland.no-ip.org/zip/SpaceshipsV2.zip (2.08MB)
http://gurpsland.no-ip.org/zip/SpaceshipsV2.7z (903KB)

Excel 2007
http://gurpsland.no-ip.org/zip/SpaceshipsV2-2007.zip (2.74MB)
http://gurpsland.no-ip.org/zip/SpaceshipsV2-2007.7z (2.64MB)

OpenOffice 3.3.0
http://gurpsland.no-ip.org/zip/SpaceshipsV2-Ooo.zip (2.00MB)
http://gurpsland.no-ip.org/zip/SpaceshipsV2-Ooo.7z (1.75MB)


NOTE: From preliminary testing OpenOffice 3.4.1 seems to work pretty well, as does LibreOffice 4.

Re: GURPS Spaceships Design Spreadsheet
 

Excel 2013 pops up an error saying it needs to be repaired and it fixes it by removing "sheet2.xml part." It seems to function normally afterward, but the fix won't save into a new template.

I'll post more later.

Edit: Apparently opening it as a saved template causes the problem. If it's opened as a standard spreadsheet no error pops up. I think it clears out data to turn it into a template (since the file size changes so much) that the spreadsheet actually needs to operate.

Re: GURPS Spaceships Design Spreadsheet
 

Hi ericbsmith,

I'm using Excel 2010 and I can't seem to figure out how to enable the macros in both the 2000 and 2007 Spaceships spreadsheets. I was successful in opening the OpenOffice version.

The spreadsheet in looks great in both Excel and OpenOffice. Thanks for the work.

Re: GURPS Spaceships Design Spreadsheet
 

I would imagine in Office 2010 that you must create a security exception for the folder the same way you would in Office 2007:

In Microsoft Office 2007 you can create a Security Exception under:
Office Button (top-left corner) -> Excel Options (button) -> Trust Center -> Trust Center Settings (button) -> Trusted Locations

Re: GURPS Spaceships Design Spreadsheet
 

Thanks ericbsmith I'll give the process ago, I can't do any worse than I have already. At least I can use the OpenOffice version.

Re: GURPS Spaceships Design Spreadsheet
 

Hi everyone.
When you use the spreadsheet to mix different engine types together, it uses the delta-v of one or the other.
For example, if at TL9 I have 2 hydrogen fuel tanks, 1 nuclear lightbulb engine (0.45 mps per tank) and 1 nuclear thermal rocket (0.8 mps per tank), it lists 0.9 mps and 1.6 mps in the list of engines, but the final delta-v is 1.6 mps.
What would the actual delta-v be? An average of the two? (since they are sharing the same tanks?)

Re: GURPS Spaceships Design Spreadsheet
 

Note: I saw your post pre-edit, and from that the first thing you have to understand is that delta-V means, literally, "change in velocity." The rated delta-V is basically a measure of how efficiently a particular engine type uses it's fuel - the higher the delta-V the more efficiently it uses it's fuel to convert it into a change in velocity. Since delta-V is basically a measure of efficiency it does not change no matter how many engines you add to a ship.

If they're sharing the same fuel tank the final delta-V is going to be some value between the higher and lower value. If you run the nuclear lightbulb engine to use 100% of the fuel the delta-V will be 0.9, if run the nuclear thermal rocket to use 100% of the fuel the delta-V will be 1.6. Or you can split the difference by running each engine for any percentage in between and wind up with a delta-V of any value between 0.9 and 1.6.

Realistically, and generally speaking, mixing two different engines is very inefficient, as the extra engine is going to cause you to have less fuel on board and cost more money as well. The main exception to that is when you have a high-thrust low delta-V engine to lift off from a planet then a low-thrust high delta-V engine to travel from orbit to wherever your destination is, for instance using a Chemical Rocket for take off and an ion drive for space propulsion to reach Mars. These two engines aren't really that far apart - replacing the Nuclear Light Bulb with another fuel tank will increase the delta-V of the NTR rocket to 1.35, which is close to the maximum delta-V having two drives installed.