[CT] Starter Traveller Range Bands = Hexes

[Longboat]

First, is this the forum where we discuss CT? If not, moddies, please move it to the correct forum.

In another thread, I mentioned that I would use the Starter Traveller Range Bands on a hex map. It is very easy to do. Every hex represents 10,000 km. A ship can move change its velocity by 1 hex per Maneuver Drive level each starship combat round (each round is 1,000 seconds, as it says in the book). Thus a ship with an M-1 Drive can go from relative stop to 1 hex per round by accelerating at full thrust for 1,000 seconds or 1 starship combat round.

Think of the M-Drive number as movement points.

A Beowulf Free Trader would be at relative rest--maybe docked to an orbital starport, and then be 1 hex away 1 combat round later. If the ship fired its drive for one round and then shut them off, then the ship would continually move one hex each round.

Of course, Traveller ships usually move at full thrust until midpoint to their destination, flip, then decelerate on the second half of the journey. So, a Free Trader can increase his velocity (velocity = number of hexes moved each round) by 1 each combat round.

From a relative stop, a Free Trader with an M-1 drive would move 1 hex on round one, then 2 hexes on round 2, then three hexes on round 3, and so on. Each round, the ship is still accelerating, so if on round three the ship is moving at 3 hexes per round (has a velocity of 3), then it would accelerate to a velocity of 4 hexes per round on round 4.

If a ship has an M-3 drive: from a relative stop, it moves 3 hexes on round one, increased to 6 hexes per round on round two, increased to 9 hexes per round on round three, and so on.

What I think is neat is that this really shows your players the difference in M-Drives. They see how much faster a M-3 ship can be, compared to a M-1 ship. It's right there in their face as the M-1 ship slowly increases velocity each round, but the M-3 ship takes off like a bat out of hell when compared to the much slower vessel.



M-Drive number tells you how many hexes the ship can add or subtract from its velocity per round.

Velocity is the number of hexes a ship moves per round.

Each round is 1,000 seconds.

Each hex represents 10,000 km.





MANERVERABILITY

Up until now, we've only been discussing the ship moving in straight lines across a hex map. We've seen acceleration, which is equal to the ship's M-Drive number (how many hexes a ship can add or subtract from its velocity). Velocity is the number of hexes a ship moves each round.

If a Free Trader with an M-1 drive has a velocity of 9 (that's 9 hexes per round achieved by accelerating at full drive thrust for 9 rounds or 9,000 seconds, which is 2.5 hours), the ship can cut its drive and continue at a velocity of 9 hexes per round. Or, it can slap the M-Drive on full and increase velocity to 10. Or, the ship can flip and throw its drive on against its direction of movement, slowing velocity by 1 hex (the level of M-Drive), spending that round to decelerate from a velocity of 9 to 8.

But, ships don't just move in straight lines. How do you handle this momentum? You count out the ship's velocity in hexes, and from that last hex, allow your ship to move in any direction by an amount equal to the ship's M-Drive.

Thus, picture a Free Trader on a hex map at a velocity of 9. On the next round, move the ship 9 hexes in a straight line in the direction of its thrust. Then, on the last hex, allow the ship to move into any touching hex (since it's a M-1 ship).

Again, this shows players how weak or strong a ship can be when fighting its momentum that its built up over rounds and rounds of acceleration.

If a Free Trader has spent 9 combat rounds accelerating to a velocity of 9 (moving 90,000 km in 1000 seconds, or 90 km per second), then its going to take another 9 rounds to decelerate so that it can dock at a starport.

You don't have to use the Traveller equation if the destination is on the hex map. Just count the number of hexes to the destination (let's say an orbital starport) and cut that number in half. That will tell you how many hexes the ship will have to cover at max thrust, and do the same distance to decelerate so that the vessel doesn't fly past the starport (or crash into it).

A ship with an M-3 drive can get to velocity 9 in just three starship combat rounds--3,000 seconds. If you move the M-3 ship 9 hexes for the next round, you can then find the last hex and adjust position in any direction by 3 hexes. This will show players how much more maneuverable an M-3 ship is when compared to a M-1 ship.



Does this sound complicated? It's really not. It's easier to understand when seeing it on a hex map. The concept is really super easy.

 

[Sigtrygg]

There is a bit of an issue, your retained momentum.

Using your example I start with a velocity of 9 and move forward 9 hexes (lets's number the hex sides 1-6 with 1 being forward) I can then move 3 adjacent hexes in any direction, let's say I pick 2 then 3 then 2 again- what happens on the next turn? I move 9 forward (direction 1) and 2 in direction 2 and one in direction 3. I may then allocate another 3 hexes into any adjacent hex.

What is happening is your velocity is building up in several directiosn, this can be resolved using vector addition to get a resultant direction or here is a simple way to do it.

For each ship have a hex - labelled 1 to 6. Each turn write down the velocity in that direction, keeping in mind that opposite faces can be subtraced from each other to get the resultant easily.

Each turn move the ship counter in the direction of its highest velocity first, then second highest then third etc until you have spent all your momentum to establish where the ship would be if it didn't accelerate that turn. Then allocate this turns maneuver points (for added complication this can be done in writing and not revealed until everyone has plotted movement).

One other complication I add taken from Mayday - use of the evade program costs you one of your maneuver drive points for that turn, so an m3 drive only gets t hexes to change if they evade.

 

[Longboat]

There is a bit of an issue, your retained momentum.

Using your example I start with a velocity of 9 and move forward 9 hexes (lets's number the hex sides 1-6 with 1 being forward) I can then move 3 adjacent hexes in any direction, let's say I pick 2 then 3 then 2 again- what happens on the next turn? I move 9 forward (direction 1) and 2 in direction 2 and one in direction 3. I may then allocate another 3 hexes into any adjacent hex.

What is happening is your velocity is building up in several directiosn, this can be resolved using vector addition to get a resultant direction or here is a simple way to do it.

I'm not sure you understand.

Your velocity is 9. You have a M-1 drive. And, you're moving in the direction we labeled 1.

You move 9 hexes in direction 1, then move the ending point to hex 2. (Clockwise would be to the right).

Your direction is still 1. You've altered velocity enough to move the line over one hex.


On the map below, you move 9 hexes and end up in hex 0209. Direction 1 would be moving into hex 0309. With your M-1 drive, you can stay in 0209 or move into any of these hexes: 0309, 0310, 0210, 0110, 0109, or 0208.

You decided to throw your thrust to turn "right", and you ended moving your end point from 0209 to 0310.

Now, your thrust will move you up through 0409, 0509, ... , ending in, well, off the map. Let's adjust and say you end up in 0205 of the next grid over. Now you want to move to hex 0206, and this slows your velocity to 8.

For the next round, you move 8 hexes, ending in 1002. You'll have to adjust the map again, but you get the idea.

Next round, from your new hex, you move the ship 9 hexes in direction 1. At the end hex, you move to hex 3.

 

[Sigtrygg]

The way I describe it is a simple way to model momentum preservation, At a m-1 rating the effect is the same. Nine in direction 1 and one in direction 2. I think we both end up in the same place. The next turn I move nine in direction one but I have to move the one in direction 2 otherwise the momentum generated last turn has magically disappeared.

Imagine an observer moving at nine alongside you, so you are stationary in your frame of reference. What will your one turn of m1 acceleration in direction 2 produce?

Each of the directions 1,2,6 have you moveing up the map - positive.
The directions 3,4,5 are negative - you will move down the map or decelerate if already moving up the map,

Consider each direction 1,2,3,4,5,6 as a frame of reference, you have to move your momentum from last turn.

At the end of a turn you are likely you could have 9(1), 4(2), 2(6). it looks worse than it actually plays.

At then end of each turn resolve your vectors by 1-4, 2-5, 6-3 this again is much easier when you see it rather than try to explain it.

I may not be explaining what I mean well enough but it does work and provides an alternative to the multiple counters to plot past, present and future position, or drawing displacement vector arrows.

The hidden plotting of your acceleration intention this turn has an additional benefit, it can be used during combat, your opponent has to nominate which hex or hexes he wishes to fire into, for missiles this could mean you could evade, the advantage is still with the missile in that any of its movement can pass within yours and it hits. But there is a chance the controlling player guesses completely the wrong hex and none of the missiles movement passes through it.

 

[Longboat]

Most players I've played with have seen too much Star Wars. Heck, even Babylon 5 and the new Battlestar Galactica showed some powerful zero-G maneuvers, but players still think that ships can zip around in any direction like dog fight WWII fighters.

The hex board gives them the reality of it. A ship may want to "turn left" at a specific point, but unless a lot of thought is put into it, the chances are the ship will fly by that point and barely be able to break vector a small amount in the new direction.

The other interesting thing is matching vectors. Players can see that it's not easy to meet another ship in space. Again, planning is needed. It's not easy to meet another ship while just flying by, or allowing the other ship to fly by.

I wonder if the new Pirates book considers that.

If there's a Pirate target out by the gas giant, and a Pirate spends 2.5 hours approaching, the Pirate really needs to hit it hard for 1.25 hours then decelerate for 1.5 hours to approach the GG. With that drive lit up and facing the GG, it should be hard for any ships at the GG to know that there's a ship approaching.

Meeting a ship to conduct piracy becomes a chess match--probably ending in the pirate disabling the target from afar and spending hours to get to the downed craft.

I'm very interested to see how the Pirate book addresses this.

 

[Longboat]

Here's a better, cleaner, example of the Starter Traveller hex system. Each hex represents 10,000 km, the distance a ship with an M-1 drive can accelerate to in one CT starship combat round, which is 1000 seconds.

A Beowulf class Free Trader exits a world's orbit into hex 0210, and our journey begins in that hex.

The ship has been hired to perform maintenance on far orbital comm repeater that is in geo-sync orbit with the planet, 80,000 km away, in hex 0202. Because of the planetary rotation and the length of time it will take a Beowulf to get out t the repeater, the satellite will be in hex 0302 by the time the ship gets there.

There may be a better way to chart the course, but this is what this ship captain does...



Round 1, 1000 seconds into the journey, the ship accelerates to 0209.

Round 2, momentum carries the ship to 0208, but the Beowulf is still accelerating, so the ship, at the end of this second round, is in hex 0207. 2000 seconds into the journey.

Round 3, the ship moves through 0206 and 0205 because its velocity is 2, and the ship accelerates one more hex, ending round 3 in hex 0204. Velocity at this point is 3, and we are 3000 seconds into the journey, which is 50 minutes into the journey.

Round 4: The captain orders thrust to shift the ship trailing. So, from hex 0204, we figure ship's velocity of 3--count 3 hexes in the same direction, and then move to one of the adjoining hexes (as the ship has an M-1 drive). You start from your last position, 0204, and count three hexes in the direction of motion taking you to 0201. From there, you can shift to a connecting hex, and we'll make that 0302.



Now, that looks like the captain has hit his target on the money. But, oh no, woe his him. The ship still has a velocity of 2. The ship just can't stop in space! It's got momentum to deal with.

Round 5, the ship starts in 0302--the same hex as its destination. Velocity takes the ship 2 hexes in the same direction, coreward, taking the ship into first hex 0301 then into the next hex map, hex 0310.

The captain's calculations were off, and the ship flew by the comm repeater. From hex 0310, the ship flips 180 degrees, applies breaking thrust, and moves back into the hex map where the repeater is, 10,000 km out from it, into hex 0301, moving at a velocity of 1. Which is now perfect.

5000 seconds or over 83 minutes into the trip.

Round 6, the ship moves 1 hex, into 0302, and the Beowulf is not able to dock with the repeater and effect repairs. Total time, including the fly-by, is 6000 seconds, or 100 minutes, over an hour and a half.

Note that the ship's actual flight path is not through the hexes I mentioned. When the ship applied thrust to trailing in round 4, there's a nice rounded curve of a flight path taking the ship from its straight line of 0210 to 0204. Then the ship flips in mid-flight to decelerate a vector towards trailing. The flight path is a curve from 0204 to 0302, then straight coreward again due to momentum from 0302 to 0310 in the next hex map. Applying max thrust, the ship reverses direction to approach the comm relay from the coreward side (not the planet's side) due to the Captain's mis-judgement on approaching it.

Maybe the captain can do better on the journey back to the world.

 

[Sigtrygg]

The bit you are getting wrong is once you have applied thrust 1 in direction 2 you keep moving 1 hex in that direction every turn until you apply 1 thrust in direction 6. You have momentum magically vanishing.

Ignore your velocity in direction 1 (say it is 3), assume an observer in the same frame of reference. You apply thrust 1 in direction 2 you will now move 1 hex in direction 2 every turn until you thrust in direction 6.

Assume the observer does the same so you are both stationary from each others perspective,

You apply 1 thrust in direction 6, you now move 1 hex in direction six every turn until you apply thrust in direction 3.

To an outside observer you are now moving 3 in direction 1, 1 in direction 2 and 1 in direction 6 every turn until you fire the engines again.

There are three ways to track this - vector arrows, past/present/future position markers - or a single hex on the ship data card which you note the end of turn velocity on each face.

 

[Longboat]

The bit you are getting wrong is once you have applied thrust 1 in direction 2 you keep moving 1 hex in that direction every turn until you apply 1 thrust in direction 6. You have momentum magically vanishing.

Maybe I'm dense, and I could be. I don't think you're correct about that. An M-1 ship doesn't produce enough thrust to overcome velocity of 3 in one combat round. It would take 3 rounds to over come it. The ship does have enough thrust to bend the straight flight of velocity to curve the flight path a bit.

The ship in in hex 0410 and is moving coreward (towards the top of the hex map) at a velocity of three.

If it doesn't change velocity (no acceleration or braking), then the ship will move like this--

Round 1 hex 0410 to 0407.
Round 2 hex 0407 to 0404.
Round 3 hex 0404 to 0401.

The velocity of the ship is 3. This ship's drives are not engaged. The ship built up momentum to travel 30,000 km per 1000 seconds, or 30 km per second.



Now, in order to change its vector, which is its speed in hexes combined with its direction, the ship must apply thrust. It would take the ship 3 rounds to overcome that inertia and come to a relative stop. Lets do this in round 2 so that we don't move off the hex map.

Round 2, the ship would flip and apply thrust in direction 1 coreward. Instead of moving 0407 to 0404, the ship moves 0407 to 0405, moving just two hexes and slowing velocity to 2.

Round 3, the ship is still applying thrust to direction 1 coreward. The ship is still flipped so that the drives lead the vessel in direction 1. Normally, without thrust, the ship would move two hexes this round, 0405 to 0403, but since thrust is applied, velocity is cut again to 1. The ship moves from 0405 to 0404.

Round 4 is used to cut velocity to 0, so the ship stays in 0404. Next round the ship can start in a new direction, if it wants too.



Here's where we disagree.

The ship can apply thrust and decrease velocity, curving the ship's path. But, it takes time to over come the direction 1 inertia.

Round 1: 0210 to 0308, Velocity reduced to 2.

Round 2: 0308 to 0406. Velocity reduced to 1

Round 3: 0406 to 0506 Velocity reduced to 0 (velocity in direction 1 is now overcome).

Round 4: 0506 to 0605.

Round 5: 0605 to 0804. Velocity 2. And so on.



I think we're both working at the same idea but we're going about it differently.

 

[Sigtrygg]

Maybe I'm dense, and I could be. I don't think you're correct about that. An M-1 ship doesn't produce enough thrust to overcome velocity of 3 in one combat round.

You don't overcome it, you are adding to it. if you add to it in direction 1 you are now moving at 4, if you add it to any other face you have to move that way as well. In the real world this is a gently curving path.

It would take 3 rounds to over come it. The ship does have enough thrust to bend the straight flight of velocity to curve the flight path a bit.

Yes it does. One turn of thrust at 1 gives it a velocity of 1 in any face direction, you then move the original plus the new.

The ship in in hex 0410 and is moving coreward (towards the top of the hex map) at a velocity of three.

If it doesn't change velocity (no acceleration or braking), then the ship will move like this--

Round 1 hex 0410 to 0407.
Round 2 hex 0407 to 0404.
Round 3 hex 0404 to 0401.

The velocity of the ship is 3. This ship's drives are not engaged. The ship built up momentum to travel 30,000 km per 1000 seconds, or 30 km per second.

Correct.

Now, in order to change its vector, which is its speed in hexes combined with its direction, the ship must apply thrust. It would take the ship 3 rounds to overcome that inertia and come to a relative stop. Lets do this in round 2 so that we don't move off the hex map.

Correct, it would have to apply thrust opposite its movement for three turns to stop. if moving in direction 1 at a v of 3 it will take 3 turns of 1g thrust in direction 4 to stop.

Round 2, the ship would flip and apply thrust in direction 1 coreward. Instead of moving 0407 to 0404, the ship moves 0407 to 0405, moving just two hexes and slowing velocity to 2.

Correct (but there is a complication I will get to in a bit)

Round 3, the ship is still applying thrust to direction 1 coreward. The ship is still flipped so that the drives lead the vessel in direction 1. Normally, without thrust, the ship would move two hexes this round, 0405 to 0403, but since thrust is applied, velocity is cut again to 1. The ship moves from 0405 to 0404.

Round 4 is used to cut velocity to 0, so the ship stays in 0404. Next round the ship can start in a new direction, if it wants too.

So far so good.

Here's where we disagree.

The ship can apply thrust and decrease velocity, curving the ship's path. But, it takes time to over come the direction 1 inertia.

Round 1: 0210 to 0308, Velocity reduced to 2.

Round 2: 0308 to 0406. Velocity reduced to 1

Round 3: 0406 to 0506 Velocity reduced to 0 (velocity in direction 1 is now overcome).

Round 4: 0506 to 0605.

Round 5: 0605 to 0804. Velocity 2. And so on.



I think we're both working at the same idea but we're going about it differently.

This is where your error lies, and it is getting tricky since we are using different frames of reference. I am sticking with the ship having velocity vectors in each face direction 1 to 6 with 1 being forward.

It is perfectly possible for the dhip to aply thrust in any of these directions, it thus has a velocity in any direction it applies this thrust. The more thrust or the more turns of thrust in any particular direction the greater the velocity in that direction.

Once a ship has applied thrust in any direction the only way to stop moving in that direction is to apply equal thrust in the opposite direction.

 

[Arkathan]

If you know the location of the target at the end of your burns, rotate the map so that the endpoint is in the same hex column as your launch point.
Accelerate in a straight line half way, decelerate in a straight line until you reach your destination.
During your burns, the target will move into the destination hex.
Easy.

 

[Longboat]

I have Brilliant Lances from TNE, but I've never read it. I'd like to take some time and give it a go.

 

[Sigtrygg]

You may recognize my proposed tracking of velocity if you do

 

[collins355]

I much prefer the Power Projection system but using hexes. However, if you want to use no markers...

 

[Sigtrygg]

Hexes, two counters and a ruler.

The same can be achieved by adding a vector rosette to the SSD and just having a ship counter on the map.

 

[Longboat]

You may recognize my proposed tracking of velocity if you do

Heck, I recognize it from Mayday!

 

[Longboat]

I much prefer the Power Projection system but using hexes. However, if you want to use no markers...

How does PP work?

I remember it being a "thing" during the T4 years. I've never really looked at it.

 

[rinku]

I have to say, every time I've considered hex solutions over range band ones I end up going back to range bands. At close range, relative velocities necessarily have to be low or it's a flyby of the point of interest or a collision. At long range hitting anything except with missiles is problematic. Range bands and maybe dogfighting rules pretty much cover what you need.

There's also the problem of characters being experienced, skilled space pilots while the players are... not. That's easily sorted if things are kept a bit more abstract, and the players ability to make dumb choices in detail is removed.

 

[Longboat]

Range Bands are fine for one on one encounters. When you start adding ships to the encounter, Range Bands get cumbersome and confusing quick.

That said, Range Band starship combat from Starter Traveller is my go-to combat system most of the time.

I use a hybrid Range Band system and Roleplaying. I lay the deckplans for the player's ship on the gaming table. I play everything from the PC's perspective--what they see on scopes and their read-outs. I use Range Bands to keep track of distance between the player's ship and the bad guy.

The space combat rounds are over 16 minutes long, so with each phase, I might go into roleplay mode. As with damage to the ship. I'll describe what the player's characters know and watch them fix it. When the gunner's fire, I'm in the turret or the firing station with the character, describing to the player what his character sees.

It's quite fun running space combat this way.

 

[collins355]

How does PP work?

I remember it being a "thing" during the T4 years. I've never really looked at it.

Choose starting velocity in hexes. (Lets say 5.) Place marker five hexes ahead. When it comes time to move, advance the ship to the marker, at the same time put a marker down in the hex where the ship started out this turn. Then announce what thrust if any the ship wants to apply this turn and move the ship that many hexes in the direction you want. Lets say 2G thrust straight ahead - so move the ship another two hexes forwards. Now count back to the original position marker you dropped when you first started moving the ship this turn - this tells you where to put the future position marker down for next turn (7 hexes in advance of your ship in this case). Repeat drill next turn.

 

[Sigtrygg]

You missed out that changing facing costs a variable number of thrust points based on the size of the ship, agility and the like.