Small Ship Traveller Universe

A Small Ship Traveller Universe –  A Bit of Handwavium to explain it.

In Mongoose Traveller, Capital ships (i.e. those over 2k dTons) are required to be in section. The largest one that can be done in just 2 sections is 7,500 dTons, which, as it happens in MTU, is the largest volume that a TL 15 anti-gravity field can support. Jump drives need A/G fields to make jump bubbles, so that also limits how big a jump capable ship can be. A/G fields affecting volumes of space, not mass, also explains why space ships are sized in dTons and the mass of the ship doesn’t matter or affect how many G’s acceleration it can pull. Due to the rather massive drop in both size and cost of spinal mounts, even meson guns up to Type C (the largest being D) could be mounted in a TL 15 craft.

This was first posted to the TML, but this is the “official” blog of My Traveller Universe, so I’m putting it here so it is  made official and stuff.

Mongoose Traveller Core Rulebook MGP 3800 Part 9 Psionics.


Use the Force….

Psionics is the optional 7th characteristic, rolled the same way, but with a -1DM per terms served up to that point. Values under 0 are 0 and mean you have no psionics at all. Your current PSI characteristic is also the number of psi strength points you have to spend on powers.

Once you have found out you raw amount of skill, assuming out side of character generation1 you need to be trained. This takes 4 months and 100,000 Cr. This boils down to making a series of psi skill checks to find which talents you know. If you are still in CharGen when you get psions, training happens as part of your skill rolls.

There are 5 talents, which are (in reverse order of ease of learning)

  1. Teleportation
  2. Awareness
  3. Telekinesis
  4. Clairvoyance
  5. Telepathy

If you make you skill checks in that order it’s a flat roll plus your modifier to beat 8 to get the talent. Doing them out of that order has some DM’s based on the talent and the number of rolls you have made. The DM starts at +0 for Teleportation and ends at +4 for Telepathy, with a -1 DM per roll made to learn a talent.

Each talent is also treated as a skill, in that you gain levels in it, assuming you take a term or so in the Psionic career. Each talent is also broken up into smaller powers


  • Life Detection
  • Telempathy
  • Read Surface Thought
  • Send Thoughts
  • Probe
  • Assault


  • Sense
  • Tactical Awareness
  • Clairvoyance
  • Clairaudience
  • Clairsentience


  • Telekinesis
  • Flight
  • Telekinetic Punch
  • Microkinesis
  • Pyrokinesis


  • Suspended Animation
  • Enhanced Awareness
  • Psionically Enhanced Strength
  • Psionically Enhanced Endurance
  • Regeneration
  • Body Armor


Unlike the other talents it doesn’t have any powers under it, just it gets more and more difficult the farther you attempt to ‘port and how much you are taking with you. They still have Classic Traveller’s change in gravitational potential being a bad idea when teleporting, just for what it’s worth. The psi drugs are listed, and few pieces of psionic technology.

The Psions Career

Like the other careers it’s broke down into 3 assignments, Wild Talent, Adept and Psi-Warrior.

Luke, as a random possible psionic character, was a Citizen colonist who rolled a 12 on a his first life event then spent a bunch of terms as a psi-warrior, if you get what I mean, and I think you do.

I am iffy about psionics. If you are running in Foreven (or the Spinward Marches) you have to pay some attention to it, because of the Zhodani and, to a lesser amount the Droyne. In MTU it’s going to stay rare for PC and be mainly used by NPC/monsters, unless, like Luke, it comes up during character generation via events. I’m not going to allow PCs to pick it up post CharGen

1Several events can lead to getting to roll psionics strength, most notable a 12 on the life event table, which all careers have a chance at rolling on.

The Challenge Class 2k dTon Cruiser

The Challenge Class 2,000 dTon Cruiser1

The Challenge class cruiser is designed to be “laser proof” and very hard to hurt with any thing less than 100 dTon class bay weapons.

Component Displacement tonnage MCr Notes
2000 dTon Hull (Class L) 2K 220 Streamlined
Full RSTHR Hull skin N/a 1100
  • Reflect (+3 Armor vs Lasers)
  • Self Sealing
  • Stealth(-4 DM vs sensor lock)
  • Heat Shielding
  • Radiation Shielding (+6 vs Rad)
12 points Crystaliron Armor 300 120
  • 15  Vs Lasers
  • 18  Vs Radiation attacks
Jump Drive R 85 160 Jump 3
Jump Fuel 600 Jump 3
Maneuver Drive U 37 76 4 G Acceleration
Fusion Power Plant Class U 58 152 Rating 4
Power Plant Fuel 76  (4 weeks)
Bridge with Holographic Controls 40 12.5
Very Advanced Sensors 5 4 Radar,Lidar,Densitometer,Jammers,NAS
Computer MK IV and software 27.3

Rating 20

Software loaded

  • Library
  • Maneuver/0
  • Jump Control/3
  • Evade 2
  • Fire Control/4
  • Auto Repair/2
Weapons and Screens
5 X Large Particle Bay 500 200 9D6 plus crew hit
7 x Triple Turrets 7 35 Particle Beam (3D6 damage, plus crew hit)
8 x Triple Turrets 8 24 3 x Beam Lasers 1d6 Used for point defense.
2 x Nuclear Dampers 40 60 -4d6 Damage, No crew hit from radiation attack
2 x Meson Screens 40 120 -4d6 vs Meson weapons
Crew and Misc.
17 Statesroom 76.5 10.2


  • Commander
  • XO
  • Piloting Officer
  • Navigation Officer
  • Chief Engineer
  • Medical Officer
  • 3 x Engineering Crew
  • 2 x Screen operators
  • 20 x Gunners

Each states room has an escape pod. All the rooms, other than the commander’s are dual bunked.

Repair Drones 20 4
Full Hanger or Cargo Space 106 30 Can carry 75 dTon of craft will full access
Totals 2000 dTon 2,135 Mcr This is a rather expensive ship, but over half the cost is the hull and it’s skin. With just normal armor and skin the cost is 1,035 Mcr

1Built with Mongoose Traveller’s High Guard rules.

Mongoose Traveller, Space Combat, Part II

On The Traveller Mailing List (, subscribe by going Here if you are not a member. Go on, do it. If you are reading this you need to be on the list. I’ll wait) the viability of small combat craft got brought up as a reply to my statement about not liking masses of massive ships, with the Classic Traveller High Guard rules about size of ship vs power of weapons as an example of why you want big ships.

This is not about Classic Traveller, so it’s rules are only slightly important here, and only where they differ from Mongoose Traveller do they get brought up.  I haven’t gotten to High Guard yet, so the difference between it and CT High Guard combat hasn’t been a subject, yet.

Yes, I know Fighters in Traveller is flame bait subject, but I’m going to look at it any way.

I agree, 10 dTon fighters are damn close to useless, other than against smaller (say sub 400 dTon or so) and lightly armored space ships.  No arguments there. On the other hand, I think a 50 dTon Honor Harrington style LAC can be made that will as difficult to damage with non “capital” weapons (read a bay weapons or bigger) and that will be a threat, if only for a single volley or so, against major ships (i.e. not another small craft),  A 50 dTon LAC style craft could carry, for example 1 Torpedo and one laser (for use as point defense or vs smaller targets), which would make it a threat, if only for a single volley, against most ships.  A basic non-nuke torpedo does 4d6 damage, which, is going to penetrate most armor on an average roll, and all armor on a just slightly over average roll, just using rules as written.

Page 99 of High Guard has a 40 dTon, armor 10, 10G torpedo boat that carries 2 torpedoes. It’s fairly close to the HH style LAC as it stands, but isn’t self escorting and can be hurt by a laser or a missile. Maybe.  If they roll real high on damage.

Armor is very important in space combat in Mongoose Traveller and is fairly cheap, both in tonnage and credits.   With Rules As Written, 6 points of armor makes you invulnerable to a pulse lasers (or beam lasers if you apply the High Guard changes) and 12 points makes you beam laser (or a pulse laser with HG changes)1 lasers proof. Not going to stop a Particle Beam or a Meson weapon, but you are using turret sized lasers and non-nuke missile? I laugh at you and call you a silly person.

In MTU, I use the personal level combat rule that the effect of the to hit roll (the amount over 8 rolled, after modifiers) is applied as damage on that attack. Any effect over 6 means that 1 point of damage gets through, regardless of armor. This makes good and lucky (defined as skill level 4 and rolling a to hit of 12) gunner gets +8 damage, which against an armor 6 craft is going to do at least 3 points of damage and could do 8, assuming it’s only a 1d6 weapon, which translate to either 1 single hit, or 2 single hits, which, could, in theory, blow a fighter out of space. On the other hand, if you roll a 7 on location both times, all you did was reduce the armor by a total of 2 points.  Of course that will make the next hit do more damage. You want 6’s or 8’s if you want to kill it. Other non 7 results will result in possible “mission kills” I’ll grant, but not that expanding ball of plasma.

As my project for the day, during breaks from “Project Clean the House” I am going to design a 50 dTon LAC that is “self escorting”, an 30 dTon torpedo boat (which might no be as easy, despite 30 dTon being a sweet spot in small craft design and a 2,000 dTon 4G Jump 3 ship. The 2K ton ship would be a “Light Cruiser” in a Large Ship Traveller game, but would be a “Battle Ship” in a Small Ship Traveller game.

My Traveller Universe is a “Small Ship” game. Capital (i.e. ships over 2Ktons) are very, very rare, even in the Imperial Navy. Mongoose Traveller’s “Barrage” based combat doesn’t make this a bad as it could be. Granted it does eliminate spinal weapons, but a “large bay” comes damn close for a smaller ship. Not having capital ships also cuts down on the 9 to 37 (!) pages of tiny type ship’s maps.

Rant. Mongoose needs to stop doing that. The maps, for large ships, are too small to read and damn near useless for a ‘dungeon’ map, and in some books, just plain ugly due to the software used to draw them. Waste of book pages, In My Arrogant Opinion

1They reversed which one does 1d6 vs 2d6 in High Guard, but made pulse lasers have a -2 DM to hit. Why? I don’t freaking know.

LSP Far Venture class 400 dTon Trade Cruiser, armed varient.

Subsidized Merchant (Armed) modified Type R (Type RLA).

Major differences

  1. 4 popup turrets
  2. Jump 2
  3. Removal of 7 stateroom
  4. Removal of low berths.
  5. Modular cargo / passenger design

Subsidized Merchant, Type RLA (‘Fat Long Trader (Armed)’)

Item Tons Price (Cr.)
Hull 400 tons
Hull 8
Structure 8
Total Hull Cost 17,600,000
Armour None
Jump Drive D (Jump 2) 25 40,000,000
Maneuvering Drive C (Thrust 1) 5 12,000,000
Power Plant D 13 32,000,000
Compact Bridge 15 2,000,000
Computer Model 1bis Rating 5 (10 for Jump) 45,000
Electronics Civilian Sensors (–2 DM) 1 50,000
Weapons Fire Control 4
Pop Up Turret 1 Triple Sandcaster 1 2,750,000
Pop Up Turret 2 Dual Sandcaster, Missile Rack 1 3,250,000
Pop Up Turret 3 Triple Pulse Lasers 1 3,500,000
Pop Up Turret 4 Triple Pulse Lasers 1 3,500,000
Fuel One Jump–2 and Two weeks of operation 88
Magazine 10 Tons of munitions, normally 180 Sandcaster barrels and 12 missiles
Cargo 191 (19 10 dTon modules)
6 Staterooms for crew. 1 single, 5 double. 24 3,000,000
Extras Fuel Scoop
Fuel Processor 1 50,000
Escape Pods One for every stateroom 3 650,000
Ship’s Locker
LSP Light Launch Mod 6502 16 4,606,000
Software Jump Control/2 200,000
Fire Control/1 2,000,000
Total Tonnage and Cost 400 127,201,000cr

LSP 16 dTon Mod 6502 Light Launch

LSP Light Launch Mod 6502

The 16 dTon launch is designed to go with the “armed” version of the Far Venture class 2J merchants. It is a quite simple design, being made, mainly, to be the minimum needed to transport a 10 dTon module from a planet surface to orbit.

Part dTons Cost (CR) notes
S 1.6 Hull 16 1,276,000 Streamlined
0 hull, 1 Struct pt.
sB M Drive 1 2,000,000  (3 G Thrust)
sB FP Plant 1.5 1,000,000
Fuel 0.25 0 3 Days
Cockpit 1.5 100,000 One Crewman
Computer MK I 0 30,000 Rating 5
Air Lock 1 200,000 Includes boarding tube
Cargo 10.75 0 10 dTon as module
Totals 16 4,606,000 Cheap and dirty way of getting a LSP standard 10 dTon module into space.

Mongoose Traveller Core Rulebook MGP 3800 Part 8 Spaceship Combat

Spaceship Combat

Let’s get the elephant in the room out of the way. No Vector Movement.

Wither this is a good thing a or a bad thing depends. I think it’s a bad thing. Vector movement was an important part of Classic Traveller Space combat. Have no fear, it comes back as an alternate in High Guard

Really, the space ship rules and the non character generation rules in High Guard should be taken as a whole, which I will do, post my High Guard post(s)

So, if no vector movement, what do we have instead? Well, a band based system that used the thrust of the ship to determine how long it takes to go up or down one band. This works fine, assuming 2 ships, because, after 2 points makes a line. With 3 or more, life gets ugly. Ugly enough as to almost be unplayable, giving the fact that the bands aren’t the same size. Making tactical movements is really, really tricky. As I said, Vector movement, The One True Movement System For Traveller Space, comes back in High Guard, but as it stands, ick.

All that being said, the TMB space combat system really does work well for 2 ships. The postion of all the members of the crew needs to be determined, but that’s sort of a given assuming you have a full crew.

Steps in combat are

  1. Set up.
  2. Manoeuvre
  3. Combat
  4. Ship’s Action

Set up

This is just the find range, find where every one is located at, determine initiative, like the set up in damn near all modern role playing games.


This is some what simplified, given the lack of vector movement, it’s just a matter of deciding how many of your thrust points you want to apply towards changing range bands (and if going up or down the scale) and how many you are keeping to dodge and like that with.


Combat is very much like personal combat, as far a rules mechanics go, in that you roll 2 dice, plus modifiers based on weapon type vs range and the skill of the gunner to get 8+ to hit, armor reduces damage and the target can take reactions to coming under fire to modify your chance of a hit. The number of reactions depends on the number of thrust points the target ship has left after the manoeuvre phase. On of the possible actions that uses a thrust point is “line up a shot”, which makes a pilot check part of a task train for taking the shot. It’s not quite clear if this applies to all shots that turn or just to one, but I rule it’s for all shots, based on the wording “his gunners”, not “a gunner”, but I can see why some one might think it only applies a single shot. Not a game killer either way.
Beam weapons are done per each, not per turret. Missiles, at least in the no vector version, have a turn until impact based on their range, or, if you want to be crazy, they are a thrust 5 ship. Gah. Tracking that many on the band based system? Ouch.

There is a “quick boarding actions” chart, in case you don’t want to do a normal Traveller combat to solve the assault.

Ship Action Phase

In this phase you may attempt to repair damage systems, get (or break) a sensor lock, attempts to increase your initiative or change positions with in the ship.


Damage is tracked via the same system as vehicles, in that there is two types of damage points, hull and structure, and you don’t take structure damage, in general, until you are out of hull points. The total amount of damage a hit does is cross referenced against a chart which reduces it to “single, double or triple” hits against a given system on the ship. The effects of single etc hits is listed per system. Stronger hits might do multiple single etc hits, as an example, 37-40 points of damage is going to do a triple, a double and a single hit. Each of these hits would be rolled on the target chart to determine what got kissed.

The chapter ends with a shadow text block explaining that a starship class weapon does 50x damage, so if you roll 6, you are doing 300 damage on the personal/vehicle damage levels.

Next up, Psionics!