"Traveller Spaceship Weapons Ranges? CT" Topic

I am considering giving Classic Traveller a go for a small spacebattle, or three, using "adventure class" ships, e.g. those little free traders, far traders, close escorts, spacefighters, etc., and noticed in the Starships book that there is no info on weapons ranges, or sensor ranges, other than short and long.

For the first game, I'm going to have a modified free trader (Maneuver 2, instead of the normal Man. 1) attempt to leave a blockaded planet, and to try to jump to hyperspace without getting caught, and stopped/destroyed. I know, shades of Star Wars, Episode 4. The blockading vessel will be a Gazelle-class, close escort.

Still working out the relative distances, world diameter, ship positions, etc., in order to try to give the merchant a chance, but make it interesting.

I'll probably use my modified house rule for making the jump in less than 1,000 diameters from the planet. Further away is safer, but obviously takes a long time to get that far out, so will let the pilot jump closer, if desired, with an increased chance for a jump failure/misjump.

May modify the misjump results too a bit, to make them interesting, e.g. vessel jump doesn't succeed, so ship remains at sublight speed; jump doesn't succeed and vessel incurs jump engine damage – X turns to repair; jump warning system cancels FTL entry – retry in X number of turns, once the nav computer plots a solution; etc.;, instead of letting the pilot automatically "misjump" far, far away, in order to give the pursuer a better chance of catching the blockade runner.

I did run across a nice posting of Sensor Ranges on the CotI site, and inquired about the Weapons Range issue there as well.

Anyone have thoughts, or data on ranges for the following, small vessel weapons?

Beam Lasers
Pulse Lasers
Particle Accelerators
Small Turret Missiles
Larger Bay Launcher Missiles
Meson Guns, etc.

I suspect missile ranges can be a function of their accel in Gs, and fuel available, tied in with the sensor ranges of the vessel, when launching them.

I seem to remember that the first range band was 150,000 km, and the second 300,000 km …?

Yea, there are a couple of schools of thought/options provided for the Sensors, which may equal the Laser Ranges:

Merchants – Detection Ranges

Option 1 – 150,000 kms

Option 2, as below:

Close Range 100,000 kms
Short Range 150,000 kms
Long Range 300,000 kms
Extreme Range 600,000 kms

Tracking range, once object detected = 900,000 kms

Military Sensor Ranges – Detection:

Option 1 = 600,000 kms., or 900,000 kms

Option 2:

Close 300,000 kms
Short 600,000 kms
Long 900,000 kms
Extreme 1,200,000 kms

Tracking Range = further of 900,000 kms, or initial detection range, whichever is greater

Visual Detection Range = 10,000 kms

In The Traveller Book (which was sort of the three LBBs collected into a single hardback …), lasers had their range limited only my the ability of sensors to detect the target. However, there were range modifiers for accuracy.

Civilian ships can detect (any) other ships out to a half light second.

Military ships can detect other ships out to three light seconds.

Ships that have been detected can then be tracked out to three light seconds. However, the rules don't specify if one ship can detect a target and then hand the detection off to other ships, or if every ship detects targets completely independently.

Lasers suffer at -2 modifier to their hit rolls (on 2D6) beyond 250,000km. That's almost one light second (300,000km), and is well beyond civilian detection range. This can make things very, very bad for a free trader fighting a Gazelle-class close escort …

Beyond 500,000km, lasers suffer a -5 modifier. (That's 5/6 of military detection range.) Since you're trying to roll 8+, that's a pretty serious modifier. (Various gunnery and evasion computer programs give more modifiers.)

Incredibly, thrust and endurance for missiles isn't given! From other sources, the big factor is whether the missile has constant thrust or if it can turn off its motor and drift. When the motor burns out, the missile can't maneuver to hit its target … If it can drift, a missile's range extends at least out to the launching ship's detection/tracking range. A homing missile could pursue well beyond that, since it doesn't require the launching ship's sensors.

Thanks for the info.

Yes, I'm beginning to see that the little free trader may be a bit overmatched, even if I do give it an illegal, military-grade, sensor package. Perhaps some sort of Patrol Boat might be better as an opponent.

Hmmm, will need to think about that a bit more, or switch out the laser turret, on the merchant, for two missile turrets.

I ran across some stats that give some info on various types of missiles, most of which are 6G, but there were 9G, and 12G entries too. Fuel capacity was listed in hours, and ranged from about 30 – 36, up to a high of 72, I think, so plenty of ability to chase anyone thinking of outrunning them.

Check Striker, it might help

Brillaint Lances might have more specific info – it was a good traveller ship combat system.

Mako, those endurances may be for Brilliant Lances, which had 30 minute turns. CT assumed turns of 1000 seconds: 16.67 minutes. Mayday and Special Supplement 3, the most burns a missile design have have is 12 G, and many will have less. That could be 12 turns of 1G acceleration, 2 turns of 6G acceleration, and so forth. Constant burn missiles always thrust their maxiumum, limited burn missiles set their thrust at launch and then can't change it, and discretionary burn missiles can pick their thrust and can even turn off their motor and coast.

They were from a Mayday update, I think listed as 4.1.

On the first page it mentioned one hour turns.

Can't seem the find the missile data now, so that may not have been in the Mayday 4.1 update, as above (not sure where it went).

I've also seen 20 minute turns mentioned in some Traveller variants, as well.

Given that the missiles are supposed to be pretty smaller (maybe not in Mayday – don't really know what size vessels and weapons its geared too), I did think the G thrust ratings and number of hours of endurance were pretty over the top.

a Gazelle is armed with 2 Particle Barbettes and 2 triple laser turrets. Its maneuver is also a 4 vs the trader's 2. It also has a 20t gig that mounts a laser and can man at 6g's.

Thanks for the info on the Gazelle.

I've seen different maneuver ratings for it, e.g. Man3 if with tanks; Man4 if dropped. Also, Man4 and Man5 respectively too, so obviously different designs, or tech levels.

Forgot about the gig.

Man, those free traders are screwed.

Mayday 4.1 isn't Mayday and isn't CT. So, there's that.

As M005 says, that Gazelle is just going to rip the trader in half. Use the lasers to shoot down missiles on the way in, then shoot up the trader when its tubes are empty. When you get in good PA range, you cut the trader in half and kill all the crew through radiation exposure.

There is no stealth in space (a long and well argued point). Given that, being out gunned and out maneuvered by the Gazelle means that it's up to the shady streetwise crew to talk their way past the patrol or to have an elaborate decoy. The Gazelle will fully destroy them without question, otherwise.

Just ran some numbers:

At 1G, a missile takes 92 mins to get 150,000km, and 260 to travel 1,200,000 km at constant thrust.

At 12G, it takes:
27 mins to 150kkm
34 mins to 250kkm
37 mins to 300kkm
53 mins to 600kkm
65 mins to 900kkm
75 mins to 1200kkm

go silent go deep. stay close to gaseous anomally. turn off active sensors.Space is a wide deep place. The ship (Gazelle) would know where to search before it spots you. Get to Jump range.

by then it is too late. helps to have a captain -3, navigator 3 ability on board.
Role played this before.

pulse lasers are 50,000 km. -2 penetration.

pulse lasers are 50,000 km. -2 penetration.

What rules are you using? 50,000 km is too short for Traveller lasers in all rules I'm immediately familiar with, and pretty seriously short given the very high sustained thrust the Traveller ships can achieve (as Badgers demonstrates in his post above. At only 1G, you can cross 150,000 km in an hour and a half.