When we last left hyperspace we had discovered that
1) Stars have a number of 'membranes' determined by their size.
3) You have some choice of which area to exit in, if several membranes overlap.
|This is a hyperspace map, perhaps from a children's book or a media production. Do NOT use it for navigation purposes. Though a real navigator would know that and if you aren't a real navigator-don't touch anything!|
Well then we have a number of problems integrating this into ahuhu! 2d6 systems. To wit: 2d6 systems have these lovely charts of ftl engines (skirting copyrights here) indexed against increasingly huge hulls. Cross index the drive with the hull and either it don't fit or you get a number of parsecs range the ship may jump. My set up pretty imagines it like the Alderson Drive from Jerry Pournelle's future history. You get to a point (determined very carefully) hit the drive and bang (well hopefully you didn't hear a bang, that'd be very bad)! You're in the next star system. There is no skipping star systems. Essentially a ship (any ship) has a range of 1 jump (though that jump could be Lurrdy knows how many parsecs.
Most Interstellar Empire settings reserve better gear for the military because they are the MILITARY dammit! In many 2d6 settings, for example, commercial traffic travels at 1 pc a week, faster commercial traffic (express runs) and auxiliary military (those ships some Service hands out to their vet, lok like pizza slices) 2 pc, slow military at 3 pc etc. How to give some people an edge?
Well first there is fuel efficiency. Perhaps each level is the number of jumps you can make between topping off the tanks or recharging or some such. So if a ship needs 10 tons of fuel to make a jump with a jump-1 it needs one sixth that with a J-6 or whatever scale you set up for your setting. Having a ship with less need for fuel is a huge advantage in most settings.
Fuel efficiency is even more important if your precious drive requires specialized fuel that you can't synthesize en route. Maybe there is no such thing as a ship board fuel refinery? Refined fuels must be purchased at installations. In this case logistics becomes crucial for an invasion or colonizing effort. It also means if you really want to have adventures you tinker with fuel use. Maybe a flat 10% per jump if you go by 2d6.
No, I don't now why it would have to be like that. Ask an engineer. Those guys are great at telling you why you can't do something and then making it work. It's the only profession that likes proving itself wrong.
Another possibility is to give engines saving throws vs. local effects, nebulas, strongly ionized regions, radiation belts or frequent flares. A military ship or explorer should be able to go anywhere. Some untrusting types might plant secret bases and such in dangerous areas just to keep you from popping in, taking a few scans and popping out for this reason. If the Dubbel-Tok Effect blows your drive or even delays jumping out, things might get hot for you.
One final thought. When size and expense of a drive merely determines range you have fewer options constructing ships. All J-3 ftl drives are alike. They let you jump 3 parsecs (or whatever). But with the effects I mentioned, let's say each level of drive e can reduce fuel use by 15%, or gives you a +1 modifier to avoid drive damage, or displace your ship .1 AU from the jump point of your destination.
A pirate might use all three levels of J-drive to displace his ship .3 AUs away from the average entry point. He wants to avoid the law. A merchant does the same because he wants to stick his ship as close to the destination planets and stations as possible. In an M star system like Trappist you might be able to appear anywhere in the Goldilocks zone and give your M-drive a rest.
An explorer vessel ready to jump into the unknown might got for fuel efficiency, using only 55% of fuel they would use otherwise. Or a ship about to jump into a nebula known for raising hell with electronics would take all three levels as a +3 modifier to avoid damage on a jump, and misjumping. Finally, a new system for noting these ginchy jump drives if you play 2d6 and like fitting everything on index cards.
J-3 +1, +1FE, .1AU
The drive above has a +1 mod to rolls to prevent misjumsp and damage to drive, one level of fuel efficiency (15% less fuel), and can exit .1 AU from the jump point.
Next Monday we get into misjumps and similar hilarity.