Proposed Maneuver Standard Term- V

[kilemall]

While discussing this and that here in Fleet, I've often referred to something going say 20 Gs as a shorthand reference for their velocity.

I am often 'corrected' that G is a term for acceleration, which is true.

However, it's just too useful for actual ship maneuver ala CT miniatures and the HG versions thereof. You can reference the ship's velocity and apply the G maneuvers to change course, decel, work out closing velocities, etc.

Delta-vee is of course the right term.

I could see it being melted down in star crew vernacular to dee-vee as shorthand, and ultimately vee.

So my proposal is that we refer to ship velocity as V, and that V is whatever time/distance scale is appropriate to the system proportionate to G.

That's an important distinction to make, as Mayday and Brilliant Lances' scale is different from MgT or CT miniature movement.

For CT V would be value x 10 kps, in keeping with the 10 meter per second accel over 1000s time/distance scale.

A 1-G capable ship going 10 V and wanting to decel to 1 V would need 9 turns/9000 seconds to do so.

 

[AnotherDilbert]

Gturn is the simple answer, that is the speed achieved by accelerating by 1 G for 1 turn. It was used in at least TNE.

 

[Adam Dray]

I think, technically, delta-v is how much change in velocity a given ship can perform given the amount of fuel it's carrying, so it applies more to rockets and less to M-drive Traveller ships that can operate for many weeks at constant thrust.

Ultimately, I think keeping starship combat (especially ranges) very abstract is best, unless you want to go the opposite direction and actually put ships on a map and deal with vectors.

 

[mike wightman]

There is a bogey inbound at 15V...
hmm, I could use this with a simple range band system.

Note, for a range band system to work the range bands have to be the same distance apart.

 

[kilemall]

I think, technically, delta-v is how much change in velocity a given ship can perform given the amount of fuel it's carrying, so it applies more to rockets and less to M-drive Traveller ships that can operate for many weeks at constant thrust.

Ultimately, I think keeping starship combat (especially ranges) very abstract is best, unless you want to go the opposite direction and actually put ships on a map and deal with vectors.

I rather thought I made it pretty clear that's exactly what I want to do.

HATE range bands for RPG maneuver. For ground combat too.

 

[kilemall]

Gturn is the simple answer, that is the speed achieved by accelerating by 1 G for 1 turn. It was used in at least TNE.

Hmmm, Gturn would cover the same ground as a gaming term, but I'm thinking about what space crew would use which isn't going to be 'turns'.

 

[AnotherDilbert]

..., but I'm thinking about what space crew would use which isn't going to be 'turns'.

A real crew would use a real units like m/s.

If you want a less gamey simplification you might use gh [g-hour], which in MgT2 happens to be exactly 10 gturn and easy to keep track of. So, accelerating by 1 g for 1 turn would give you a speed of 1 g × 0.1 h = 0.1 gh. Accelerating by 2 g for 3 hours would give you a speed of 2 g × 3 h = 6 gh. Easy to calculate in your head and easy to keep track of.

Distance travelled would be D = At²/2 = 2 g × (3 h)² / 2 = 2 × 9 / 2 = 9 gh², where 1 gh² ≈ 10 m/s² × (3600 s)² = 129 600 km [ ≈ 130 000 km or very roughly 100 000 km if you prefer], so 9 gh² is 9 × 130000 ≈ 1.17 million km.


Not that it is really simpler than using SI units since the physics doesn't change. The smaller numbers might be easier to keep in the head though.

 

[kilemall]

Kinda covered that too, I was saying V in a CT setting would mean value x 10kps.

 

[AnotherDilbert]

OK, with 1000 s turn a gturn is ≈ 10 m/s² × 1000 s = 10 km/s. Call it a Wazonga if you like, I find it easier to call it 10 km/s.


1 gturn² ≈ 10 m/s² × (1000 s)² = 10 000 km, so maps might use 10 000 km squares or hexes for simplicity.

 

[kilemall]

Probably, although again this is about ease of use in game terms while conveying the 'feel' of a future spacefaring culture's' standards.

Probably make the distinction that formal military and near planet space control comms would use mps, and internal/informal settings would use G/V.

I never used minis, always did moves on graph paper. Doing it on hex, yes I'd likely use 10,000 km hex scale for individual encounters, and a 100,000 km scale for major movements or fleet battles.

 

[TheDS]

A "real" crew would use a term like "G-hour" in a universe where thrust was measured in Gees over the course of hours. This describes exactly what you want to describe - accumulated thrust over a course of time. People with rockets (like us) might say G-minutes, with the understanding that the G is a low number, probably 0.1 or much less. The Kzinti, who have drives capable of 100 Gs or more, probably use a fraction of light speed. I use a decibel measure of light speed in some of my writing, but for game terms, you don't really want to measure things in kps, you want to measure them in turns.

(That is, 0dBc = light speed, 1/1000th light would be -30 dBc, 1/1,000,000th light would be -60 dBc, and 1/1,000,000,000th light (about a foot per second) would be -90 dBc. And Jump 6, which is about 1000 times light speed, is +30 dBc. This covers a very wide range of velocities with just a couple digits. )

The G-turn in TNE is measured in half hours, because one turn is 30 minutes. However, iirc the G-turn in TNE was used to describe delta-V, current fuel tankage, rather than a ship's current velocity. I started using Gees to measure velocity because of this, but was not satisfied due to the obvious confusion it could cause to listeners.

 

[Travellerspud]

(That is, 0dBc = light speed, 1/1000th light would be -30 dBc, 1/1,000,000th light would be -60 dBc, and 1/1,000,000,000th light (about a foot per second) would be -90 dBc. And Jump 6, which is about 1000 times light speed, is +30 dBc. This covers a very wide range of velocities with just a couple digits. )

interesting way to refer to velocity...really illustrates the power of an exponential scale (our hearing has a similar range, 120dB - 30dB, or 90dB total range, same as the light-speed to foot-per-second speed range, 90dB)

 

[kilemall]

A "real" crew would use a term like "G-hour" in a universe where thrust was measured in Gees over the course of hours. This describes exactly what you want to describe - accumulated thrust over a course of time. People with rockets (like us) might say G-minutes, with the understanding that the G is a low number, probably 0.1 or much less. The Kzinti, who have drives capable of 100 Gs or more, probably use a fraction of light speed. I use a decibel measure of light speed in some of my writing, but for game terms, you don't really want to measure things in kps, you want to measure them in turns.

(That is, 0dBc = light speed, 1/1000th light would be -30 dBc, 1/1,000,000th light would be -60 dBc, and 1/1,000,000,000th light (about a foot per second) would be -90 dBc. And Jump 6, which is about 1000 times light speed, is +30 dBc. This covers a very wide range of velocities with just a couple digits. )

The G-turn in TNE is measured in half hours, because one turn is 30 minutes. However, iirc the G-turn in TNE was used to describe delta-V, current fuel tankage, rather than a ship's current velocity. I started using Gees to measure velocity because of this, but was not satisfied due to the obvious confusion it could cause to listeners.

The tendency is to minimize terminology to as few syllables as possible. V is about as short as it gets.


Also don't like G/hours, it's fuzzy, better to just express km per second and let the crew calc how much G they can decel/accel to affect it.


And again, simpler for players. 20V, have 2-G M-drive, 10 turns or 10,000 seconds to decel to 0V. Easy.

 

[AnotherDilbert]

Also don't like G/hours, it's fuzzy, better to just express km per second and let the crew calc how much G they can decel/accel to affect it.

Please, not g/h (= gravities per hour), it's gh (= gravity × hour).

m/s and gh (or gturn) is the same thing and exactly as well defined. gh is just a bigger unit, so smaller numbers are needed to describe the same speed.


Example: You are accelerating at 2 g for 3 hours:

gh: Speed is 2 g × 3 h = 6 gh.

m/s: Speed is 2 × 10 m/s² × 3 × 3600 s = 216 km/s.

Both ways say exactly the same thing, since 1 gh = 10 m/s² × 3600 s = 36 km/s that means 6 gh = 6 × 36 km/s = 216 km/s.


P.S. 'G' means giga = billion, so a Gh is 1 gigahour = 1 billion hours. For a standard gravity 'g' is preferable.