Building a STL drive compound/power

[Narf the Mouse]

I've taken a large number of stabs at a realistic STL drive. It seems to have come down to a few options:

 

1) Some variation of Flight and/or Telekinesis, neither of which scales well,

2) Make a new power.

 

Any options I'm missing, or is it down to #2?

[megaplayboy]

Re: Building a STL drive compound/power

 

I've taken a large number of stabs at a realistic STL drive. It seems to have come down to a few options:

 

1) Some variation of Flight and/or Telekinesis, neither of which scales well,

2) Make a new power.

 

Any options I'm missing, or is it down to #2?

 

What's wrong with Megascale Flight? It's now scalable between levels. A SPD 3 ship with 40m flight is capable of 10m/sec(36kph) speed, and with one level of megascale, that becomes 10km/second(close to escape velocity). With 4 levels of megascale, 10,000km per second(about 3 percent of light speed), and with 5 levels, 100,000km per second. You can probably apply a limitation which sets your maximum acceleration/deceleration to, say, 100m/second/second(10 Gs), in order to make it "semi-realistic". The only downside is that it will take forever to accelerate up to even a decent interplanetary speed, and also forever to slow down in order to land or achieve orbit.

[Narf the Mouse]

Re: Building a STL drive compound/power

 

What's wrong with Megascale Flight? It's now scalable between levels. A SPD 3 ship with 40m flight is capable of 10m/sec(36kph) speed' date=' and with one level of megascale, that becomes 10km/second(close to escape velocity). With 4 levels of megascale, 10,000km per second(about 3 percent of light speed), and with 5 levels, 100,000km per second. You can probably apply a limitation which sets your maximum acceleration/deceleration to, say, 100m/second/second(10 Gs), in order to make it "semi-realistic". The only downside is that it will take forever to accelerate up to even a decent interplanetary speed, and also forever to slow down in order to land or achieve orbit.[/quote']

While that is useful, it's not what I'm looking for. By "realistic", I mean hard sci-fi, using both the speed and quantity of exhaust (maximum acceleration and acceleration relative to a mass).

[Narf the Mouse]

Re: Building a STL drive compound/power

 

One option I just thought of. When using Flight as Thrust, assume that 1m of Flight accelerates 100 kg at 1m/s/s. Then, for every +1/4 in, I dunno, "Force", assume that it accelerates x2 mass at 1m/s/s. So Flight, 10m (Thrust) (Force x16 +1) accelerates a 1,600 kg mass at 10m/s/s, or a 3,200 kg mass at 5m/s/s.

[dmjalund]

Re: Building a STL drive compound/power

 

One option I just thought of. When using Flight as Thrust' date=' assume that 1m of Flight accelerates 100 kg at 1m/s/s. Then, for every +1/4 in, I dunno, "Force", assume that it accelerates x2 mass at 1m/s/s. So Flight, 10m (Thrust) (Force x16 +1) accelerates a 1,600 kg mass at 10m/s/s, or a 3,200 kg mass at 5m/s/s.[/quote']This - and noncombat flight determined maximum speed in an atmosphere

[Ranxerox]

Re: Building a STL drive compound/power

 

Why do you need both maximum acceleration and acceleration relative to mass? Do you expect the mass of your ship to change much or the engine to be strapped on to different ships?

[Narf the Mouse]

Re: Building a STL drive compound/power

 

Why do you need both maximum acceleration and acceleration relative to mass? Do you expect the mass of your ship to change much or the engine to be strapped on to different ships?

Supposing the engine were on a freighter, such as in a generic trading game, I would expect the mass of the ship to change regularly and, hopefully for the theoretical PCs, frequently.

[Narf the Mouse]

Re: Building a STL drive compound/power

 

This - and noncombat flight determined maximum speed in an atmosphere

Have you used this in a game, or is this a common solution?

 

Bumped it up to +1/2.

[Xavier Onassiss]

Re: Building a STL drive compound/power

 

I use a combination of rules to get 'realistic' reaction drives based on Flight:

 

• Segmented Movement
  
• Cumulative Acceleration
  
• Realistic Turn Mode (home rule -- replaces 'vector-based' movement)
  
• Combat Accel/Decel
  
• No Noncombat Movement
  
• Side Effects: Rocket Exhaust
  
• One Continuous Fuel Charge (duration varies)
  

 

In Hero Designer, I just group the first three (Segmented Movement, Cumulative Accel, and Realistic Turn Modes) into a +0 Custom Modifier called Space Flight.

 

I switched to using a variant of Turn Modes in space combat instead of a more realistic vector-based system because there was always that one guy at the table who couldn't understand vectors no matter how many times you explained it to him. With a little tweaking, Turn Modes work almost as well, and all Hero players understand them.

 

Mega-scaling isn't really necessary with cumulative acceleration; depending on how many G's it can sustain, and for how long, a powerful rocket will reach 'mega' velocities anyway. (One G for one hour equals 36 km per second!) For the duration of the fuel, and other performance guidelines, you might want to check out the Atomic Rockets page.

[Hyper-Man]

Re: Building a STL drive compound/power

 

Larry Niven often used Delta V as a measure of a ships total amount of fuel available for acceleration available over a period of time.

Then there is an explanation for smaller ships being able to accelerate faster in the short term (until they are out of fuel).

This could be modeled with a custom End Reserve that interacts with a ships size via limitations.

 

Another thing to consider is whether the ships has artificial gravity and as a result some type of acceleration dampening for passengers.

If it doesn't then acceleration will be limited to what is survivable by humans (~5-10g range).

[Narf the Mouse]

Re: Building a STL drive compound/power

 

I use a combination of rules to get 'realistic' reaction drives based on Flight:

 

 

• Segmented Movement
  
• Cumulative Acceleration
  
• Realistic Turn Mode (home rule -- replaces 'vector-based' movement)
  
• Combat Accel/Decel
  
• No Noncombat Movement
  
• Side Effects: Rocket Exhaust
  
• One Continuous Fuel Charge (duration varies)
  

 

 

In Hero Designer, I just group the first three (Sugmented Movement, Cumulative Accel, and Realistic Turn Modes) into a +0 Custom Modifier called Space Flight.

 

I switched to using a variant of Turn Modes in space combat instead of a more realistic vector-based system because there was always that one guy at the table who couldn't understand vectors no matter how many times you explained it to him. With a little tweaking, Turn Modes work almost as well, and all Hero players understand them.

 

Mega-scaling isn't really necessary with cumulative acceleration; depending on how many G's it can sustain, and for how long, a powerful rocket will reach 'mega' velocities anyway. (One G for one hour equals 36 km per second!) For the duration of the fuel, and other performance guidelines, you might want to check out the Atomic Rockets page.

Thanks, I now have to fix my brain!

[dmjalund]

Re: Building a STL drive compound/power

 

I found a simplified vector system where you have a token showing where the ship is now, and another token showing (barring any maneuvering) where the ship will be next phase. when you move , you use your meters of flight from the second token and use the distance from your position at the beginning of the phase, to the position after your move, to figure where to put the "next phase " marker for your next phase

[Xavier Onassiss]

Re: Building a STL drive compound/power

 

I found a simplified vector system where you have a token showing where the ship is now' date=' and another token showing (barring any maneuvering) where the ship will be next phase. when you move , you use your meters of flight from the second token and use the distance from your position at the beginning of the phase, to the position after your move, to figure where to put the "next phase " marker for your next phase[/quote']

 

Ideally, that's what I'd use -- and believe me, I've tried. But on every single phase there's Mr. Clueless Gamer, moving the wrong counter. Someone puts it back, tells him what he's doing wrong. Blank, vacant stare. Someone helps him, and we explain how this works, for the Nth time. On his next phase, we go through the whole routine again.

 

I'm not picking on a specific Clueless Gamer here; it's not always the same guy. It's just that there's always one of them at the table, and it's not worth the trouble.

[Cancer]

Re: Building a STL drive compound/power

 

Minor question for all: how are you prepared for 3-d space combats?

[megaplayboy]

Re: Building a STL drive compound/power

 

Minor question for all: how are you prepared for 3-d space combats?

 

I suspect the use of maybe 3 hex maps might be helpful...say that the first represents the "center" of the vertical plane, one represents +20 hexes above, and the other represents -20 hexes below. For ships moving above or below these levels, use a numbered counter or colored d20 to represent where it is.

 

Definitely not for the casual sci-fi gamer though...

[Xavier Onassiss]

Re: Building a STL drive compound/power

 

Minor question for all: how are you prepared for 3-d space combats?

 

I've seen some really good rule sets for 3D space combat, but they really made my brain hurt. I've also seen some rather bad ones, which convinced me that 2-D is good enough for my RPG campaigns. For RPG purposes, space combat isn't my top priority.

 

(Oddly, I use 3-D realistic starmaps for astrogation, but it's a lot easier to handle 3-D maps out of combat!)

[Captain Obvious]

Re: Building a STL drive compound/power

 

You really only need to deal with 3D combat if there are at least four significant points of reference. Two ships dogfighting with nothing else around to run into might as well be represented with a line. If there is another ship in the fight, or some asteroid that might get in the way, you need 2D to represent everything's relation to everything else. If you add a third dimension at that point, all you're doing is altering your plane of interest from the simple tabletop to some weird, tilty plane, and then you open up the possibility that none of your ships are in the plane represented by the tabletop at all. That way lies madness.

 

I'm with Xavier here. 3D is really cool for star maps, but the benefit to effort ratio of 3D combat is just too low to justify it in a roleplaying session.

[Manic Typist]

Re: Building a STL drive compound/power

 

I found a simplified vector system where you have a token showing where the ship is now' date=' and another token showing (barring any maneuvering) where the ship will be next phase. when you move , you use your meters of flight from the second token and use the distance from your position at the beginning of the phase, to the position after your move, to figure where to put the "next phase " marker for your next phase[/quote']

 

Would you explain with a more concrete example? I believe I grasp the concept but not the steps since I lack numbers.

[shadowcat1313]

Re: Building a STL drive compound/power

 

if you want 3D space combat... look at Attack Vector Tactical and the other games from Ad Astra, Marc Miller and Ken Burnside and I discussed some ideas for a 3D version of High Guard.... and decided it was mostly unworkable

[Captain Obvious]

Re: Building a STL drive compound/power

 

Would you explain with a more concrete example? I believe I grasp the concept but not the steps since I lack numbers.

 

This page has some discussion of various systems of vector movement. They're basically all variations on the same theme, but differing explanations might make it easier to grasp. At least one of them should make some sense to you.

[shadowcat1313]

Re: Building a STL drive compound/power

 

one of my all time favorite concepts for STL drives is still the Orion/Daedalus Nuclear Pulse Drive, using focused nuclear explosions to provide your thrust

[Manic Typist]

Re: Building a STL drive compound/power

 

This page has some discussion of various systems of vector movement. They're basically all variations on the same theme' date=' but differing explanations might make it easier to grasp. At least one of them should make some sense to you.[/quote']

 

Sorry, but that link doesn't seem to work.

[Captain Obvious]

Re: Building a STL drive compound/power

 

Ah, the way the forums' hyperlink thingy works doesn't play well with copy-and-paste. It should be good now...just had to take out an extra "http://"...

[megaplayboy]

Re: Building a STL drive compound/power

 

If one is using a hex map, and working with ships travelling around twice escape velocity or faster(speeds of 20km/second or faster), then you're probably working with a 1 hex = 1 km (or even 1 hex = 10km) map scale. Now, if there's nothing like inertial dampeners in place, then most of the time the rate of acceleration/deceleration is going to be, well, about 10m/sec/sec. Sure, it could for a brief period go as high as 30-50m/sec/sec, but "safe" and comfortable crew acceleration will be in that ballpark. What's the problem? The problem is basically that your velocity at the start of space combat is likely to remain your velocity at the end, because it takes 100 seconds of 1g acceleration/deceleration to make a ship 1km/sec faster or slower. Even at the limits of human tolerance(10 gs with a g-suit on), it'd take 10 seconds(and then everybody would be passed out for a few seconds). Turning would also be similarly glacial. You pretty much have to posit "artificial gravity" and "inertial dampening" in order to have a real concept of fire and maneuver--otherwise it's pretty much "approach and fire" or "run away and fire". imo, ymmv, etc.