The THS Spaceship Thread

Negentropist · 03-08-2008, 09:14 AM

I would like to make some further enhancements to my SDV-90L design, and retcon them into the announcement from earlier in this thread.

To recap the story so far: The cheaper LSDVs are considered the wave of the future. They let more groups enter the campaign, and two LSDVs can flank a single SDV.

My SDV-90L design assumes that Vosper-Babbage, maker of the SDV-90 (THS core rulebook, p. 192), reacts by modifying its proven (i.e. fully debugged) SDV-90 design to make it price-competitive with the LSDVs listed in the THS book “Spacecraft of the Solar System.” In order to keep the marketing points of “proven design” and “maintainability”, no nanocomposites, antimatter, or elements needing debugging (e.g. new engine designs) were allowed.

The previously-posted design combined the SDV-90’s two heavy storm shelters into one 4-space shelter. This saved enough mass to upgrade the bow armor to 70/20F and replace the Ultralight fuel tanks with Light, bringing the price below the LSDV-5 and not too far above the Chinese LSDV. It also saved enough space to improve crew living conditions and add a battery that let all weapons fire in combat.

I would like to suggest some more changes that further enhance the SDV-90L’s attractiveness vs. the various LSDVs.

First, those 10 light lasers are utterly worthless in combat. At short or effective range they each do 2Dx5 damage, making them unable to penetrate a warship’s bow armor. Replace them with coilguns (which fit into the space), saving 40MW and almost $M20. No additional munitions packs are needed because the ship already carries 27 of them, and one doesn’t need many 11-gun broadsides to end a battle.

Second, yank the engines and replace them with the engines from the DFS-3, a craft that has the same size and about the same mass as the SDV-90. Which means that the SDV-90L will have performance comparable with the DFS3 and most LSDV offerings – and you’re still using a fully-debugged design component. The reduction of engine size from 375 to 250 spaces also lets you cut the retracting radiator wings by 62 ksf. Saving from engine and radiators: $M81, 156 spaces, and 810 tons.

Third, these changes create an energy shortfall of 85MW/turn. One battery pack will cover this for ten turns – more if the ship is not engaged from all sides.

Fourth, fill the vacated room with 150 spaces of fuel tank (light not ultralight, remember) and increase the rec hall by 5 spaces.

Finally, there is no reason to have the stern armored to 16cDR. Cut off 11 of that and add it to the bow. Bow armor is now 81/50F. Yes, 50F, which means that it can go head-to-head with the more-than-triple-the-price, two-beam DFS-3 and come out ahead in the radiation department.

Total price: $M650.9 – cheaper than the Chinese LSDV, yet far deadlier. sAccel is .07Gs, and delta-V is 68mps. Maintenance interval is 1.57 hours.

Definitely “SDV power at an LSDV price.”

03-08-2008, 09:14 AM	#33
Negentropist Join Date: Mar 2005	Another enhancement to the SDV-90L I would like to make some further enhancements to my SDV-90L design, and retcon them into the announcement from earlier in this thread. To recap the story so far: The cheaper LSDVs are considered the wave of the future. They let more groups enter the campaign, and two LSDVs can flank a single SDV. My SDV-90L design assumes that Vosper-Babbage, maker of the SDV-90 (THS core rulebook, p. 192), reacts by modifying its proven (i.e. fully debugged) SDV-90 design to make it price-competitive with the LSDVs listed in the THS book “Spacecraft of the Solar System.” In order to keep the marketing points of “proven design” and “maintainability”, no nanocomposites, antimatter, or elements needing debugging (e.g. new engine designs) were allowed. The previously-posted design combined the SDV-90’s two heavy storm shelters into one 4-space shelter. This saved enough mass to upgrade the bow armor to 70/20F and replace the Ultralight fuel tanks with Light, bringing the price below the LSDV-5 and not too far above the Chinese LSDV. It also saved enough space to improve crew living conditions and add a battery that let all weapons fire in combat. I would like to suggest some more changes that further enhance the SDV-90L’s attractiveness vs. the various LSDVs. First, those 10 light lasers are utterly worthless in combat. At short or effective range they each do 2Dx5 damage, making them unable to penetrate a warship’s bow armor. Replace them with coilguns (which fit into the space), saving 40MW and almost $M20. No additional munitions packs are needed because the ship already carries 27 of them, and one doesn’t need many 11-gun broadsides to end a battle. Second, yank the engines and replace them with the engines from the DFS-3, a craft that has the same size and about the same mass as the SDV-90. Which means that the SDV-90L will have performance comparable with the DFS3 and most LSDV offerings – and you’re still using a fully-debugged design component. The reduction of engine size from 375 to 250 spaces also lets you cut the retracting radiator wings by 62 ksf. Saving from engine and radiators: $M81, 156 spaces, and 810 tons. Third, these changes create an energy shortfall of 85MW/turn. One battery pack will cover this for ten turns – more if the ship is not engaged from all sides. Fourth, fill the vacated room with 150 spaces of fuel tank (light not ultralight, remember) and increase the rec hall by 5 spaces. Finally, there is no reason to have the stern armored to 16cDR. Cut off 11 of that and add it to the bow. Bow armor is now 81/50F. Yes, 50F, which means that it can go head-to-head with the more-than-triple-the-price, two-beam DFS-3 and come out ahead in the radiation department. Total price: $M650.9 – cheaper than the Chinese LSDV, yet far deadlier. sAccel is .07Gs, and delta-V is 68mps. Maintenance interval is 1.57 hours. Definitely “SDV power at an LSDV price.”