Wil's conversion for Traveller to Full Thrust [Fleet Book Rules]

Assumptions:

  1. You have access to all three rulebooks or at least FT2 and Fleetbook
  2. You want to be able to use the canonical FT FB designs
  3. The passenger and cargo rules are from More Thrust
  4. This is off the top of my head (with my copy of all three books at hand, plus Dirtside II)
  5. Abbreviations in use are
  6. Conversion based upon mass, and metric tonnage as portrayed in the Fleetbook.
  7. any number with an asterisk (*) on a damge table indicates a reroll is allowed.

Basics of Conversion

Well, based upon the fleetbook and it's construction rules, 1 mass = 100 tons mass; This would, assuming the standard Striker/MT/FF&S/FF&S2 2T per Kl [1], or about 50 Kl, and thus about 3.5 Td. This is unsatisfactory, and ships generally mass 10 tons per Td, which gives us the nice round number of 10 Td per Mass

Jump Drives

Since Jump Drives in FT are a boolean rating: You either have one or you don't. They take 10% of your mass, and require no fuel... This will never do for Traveller. We need Traveller Jump Drives. So... Since my primary Traveller ruleset is MegaTraveller, I'll base the rules of of those.

Jump Drives
Jump Range (Parsecs)123456
Jump Drive Mass (%)2%34567
Jump Fuel Mass (%)10%15%20%25%30%35%

Unlike FT jump drives (which would appear to be less efficient, and limited to about 1 parsec), Traveller jump drives require fuel, don't explode from jump entry/exit near a massive object, and aren't instant; it takes a week to go on any jump up to the drive's rating. If leaving from near a massive object (planet, moon, asteroid, etc), you may misjump. If the drive is damaged, you may misjump. Lets set misjump simply to the following: make a threshold check on the line currently being damaged; if failed cross off the line, and make a catastrophic damage check. (For our purposes, assume line 4 is a 3+). As in EFSB rules, the first JumpDrive critical result is a "Dammaged" result, and the second eliminates the drive.

Jump fuel is needed to enter jump; if you don't have enough, you don't jump. Divy the fuel into a number of icons equal to the Jump Range.

Fighters

FT Fighters are all under 100 Tons Mass, but Traveller fighters are almost all well over 10 Tons Displacement. So, I suggest rounding to the nearest 1/10th mass (rather than nearest mass) for ships under 10 mass, and simply calling them carried craft. (Mass taken for carried craft bays is 1.5x mass of the carried craft. This is more severe than Traveller, but makes sense.)

Passengers

Here we need to tweak massively: Troops go 50 per Mass Unit by MTh. We might assume this to be roughly 1 bunk each. Half-Bunks are 1/2 ton; so we could fit 20. That implies to me hot bunking... So, we'll go with the Td equivalence: 2.5 Large Staterooms per mass; This is high passengers or double occupancy low passengers. Small Staterooms (Middle passengers single occupancy, or steerage double occupancy) are 5 per mass. 10 bunks per mass for "comfortable" bunking of marines, and we'll call the 50 per mass rate "Tight Seating"; MT seating can be that cramped and still assumed to be reclineable... it's a stretch still but it works. (Short term, that would properly be 7 cramped seats; Long-Term seats are twice that and typically good for between 24 and 72 hours.)

Crew: Note that FT Crewing for military ships is roughly 1 man per mass (1 20 man crew factor per 20 mass). 1 man per 2.5 mass for merchant craft (1 CF per 50 mass). Can probably do with 1/2 this for crews with no damage control capability. This fairly well matches the "Low Automation" rates from T4's FF&S.

Weapons

Traveller ships typically use lasers, missiles, fusion and plasma weapons, plus meson weapons and particle beams in spinal mounts. Lasers, missiles, fusion, and plasma weapons are typically mounted in multiple mount turrets; Laser and missile turrets are 1 Td, Fusion and plasma 3 tons, missile barbettes 5 tons; bays are typically 50 or 100 Td. Sandcasters and repulsors, turret mounted defensive systems, are typically triple per 1 Td turret.

Lasers, Plasma, and Fusion

We'll assume that turrets are Class 1 batteries; bays would typically be class 3 for 50 ton bays, and class 4 for 100 ton bays. We'll also assume that they all work similarly, losing 1 die per unit range, variable per weapon. And we'll assume damage systems similar to the batteries from FT.

Lasers, Plasma, and Fusion
LaserPlasmaFusion
Range Increment1269
No SandSand
Roll62*1*2*2*
51012
40011
30001
20000
10000
Cost per mass234

Missiles

Traveller missiles are turret mounted, or bay mounted; barbettes are special 5 ton turrets. A group of up to 5 turrets, or two barbettes, would be one submunition pack system. Bays would become SML's and ammo; one with ammo for a 50 ton, and 2 with a single shared stock of ammo for a 100Td bay.

Particle Beams and Meson Beams

Particle beams are typically large bay or spinal mounts. Meson beams are almost always spinal mounts. We'll treat them as a variation on the Pulse Torpedo. But we'll give them a rating, too. The rating is the dice of damage on a hit. Roll for a hit, and apply damage. You can mount any size, in terms of dice, you can fit, however, if the weapon is more than 10% of the ship's mass (before adding extra arcs), it must be mounted to fire through the fore arc, and takes a -1 to hit if not within a 15 degree arc centered on the centerline of the ships facing.

Meson and Particle Beams
Particle BeamMass 4 per die,
plus (dice) per arc past the first.
Cost 3 per mass
Ignores shields; half damage rolled to armor, any remainder to hull. Not affected by any defenses.
Meson BeamMass 4 per die,
plus (dice) per arc past the first.
Cost 4 per mass
To hit and damage affected by Meson Screens. All damage direct to hull, plus any hit causes one system to make a threshold check immediately; firer's choice if a second "to hit" roll is made, otherwise target's choice. For damage, modify each die for screens.

Defenses

Meson Screens

Treat these exactly as screens from FT/FB. Except they cost only twice the mass.

Repulsors

treat these as FT PDS systems.

Sand

These are special. Each sand packet will protect versus lasers and missiles until thrust is applied, either for turning or for changing course or vector. Lasers take a reduced hit table, and if there is more than one packet, roll one die: on a roll less than the number of packets, no rerolls occur. Missiles get rolled upon; see the following table. Sand masses 1 per launcher (with one packet), and extra packets are 2 per mass. The cost of sand launchers is 2 including the first packet, and extra packets are 4 packets per point. Packets are expended when launched, but remain until movement invalidates them. When rolling sand effects against MTh Missiles, each missile is attacked by as many dice as the sand packets protecting the ship; against volley missiles, all volleys hitting together are rolled against as a group.

Sand Effects vs Missiles
Rollvs MTh MissilesVs SMR/SML volleys
612*
501
401
1-300

Black Globes

These two types of system take 1, 2, or 3 mass. Mass one systems have a 6+ roll, mass 2 have a 4+ roll, and Mass 3 systems have a 2+ roll. They have three modes: Off, Flicker, and Full On. In off mode, they have no effects. In flicker mode, roll 1d; on the assigned target number, they have intercepted the hit and no damage is marked against the ship, otherwise the hit is resolved as normal. No launching nor landing of any craft or missiles may occur while in flicker mode. In Full mode, you must plot your course and how long you will be under cover, may not fire, and may not take any unplotted actions; no craft may be launched nor landed; while in full mode, no damage gets through the globe, no roll needed. Full mode orders can include a threshold for when to come out.

The neat thing is that a globe can hold damage for later dissapation to space; the damage stopped must be tracked. You can hold up to 1/2 the ship's mass in Damage Points, plus half that again per parsec of jump capability. Extra capability comes at the rate of 10 points per additional mass. If the globe takes damage, however, it explodes, for the full ammount stored. If the capacity is exceeded, roll a threshold check on the globe, and apply the excess to hull. If you set a "Deglobe" threshold, when the total stored damage equals or exceeds the threshold, you will turn it off at the end of that turn. It is always a risk. Modes can only be changed at the end of the turn.

Full mode is effectively a cloaked ship. A gamemaster should be used if you do this, as you are detectable nearby, due to blocking out the sky behind you. Roll 1d6 per assigned firecontrol on search (it can't be used for directing fire on the same turn); roll greater than the range divided by 3 (round up) to detect, each die checked separately.

Nuclear Damper Screens

These systems prevent atomic explosions from being nearly as effective. They both reduce the number of hits from a salvo (due to non-detonation), but also reduce the damage dice as well. They also reduce each die from any missile attack. For construction purposes, assume these to be equal in cost and weight to normal FT shields

Traveller assumes either Det-Lasers or proximity nukes in all but most civilian launchers. If, for some reason, you have non-nuke missiles, halve all their damage rolls. Det-lasers are affected by Damapers since they are close enough at detonation for the explosion pumping the bomb to be affected; if it weakly detonates, the resulting x-ray laser pattern is much reduced in power. If it doesn't detonate, well, that's a miss!

Other Stuff and things not used

Things not used

There are no normal FT screens; there are multiple equivalents.
There are no wave-guns, nova canons, reflex fields, nor cloaking fields.
Area Defense Firecontrol is not available, but all traveller style ships can fire on any missiles within reach anyway! (SMR's may need to be checked for whether the flight-path is within 3", the range limit for anti-SMR fire under this conversion guide.)

Other stuff

Needle beams are a great way to represent the TL16 meson turrets. They would be affected by meson screens only.

Ortillery, minesweepers, fire control, minelaying gear, streamlining, hull strengths, armor, and general design proceedures are as per the Fleet Book rules.

Fighters represent the smallest fighters of the Traveller millieu, all types should be available, to the creative, but they are hard to design under MT or FF&S. Doable, but not economical. Do a "mini-ship", instead, for the 20-50 ton fighters. (Mini-ships, as mentioned above, round up to nearest 0.1 Mass, rather than nearest mass. If a system has a minimum mass greater than 1, it remains unchanged.

Jump drives have one additional limitation: Except under the TNE rules, there was a minimum displacement tonnage for jump-capability of 100Td. So, no jump drives on ships under mass 10, unless you want to do things the TNE way.

Travellerisms as options

TL's: JDrive range still limited by Traveller TL.

Thrust limits
TL 9: Limit thrust to 1, due to lack of gravitics; or alternately, no damage control if uusing more.
TL's 10+: limit thrust to TL-7, due to the limits of G-Comp. Again, lose the ability to do damage control, troop loading, etc, if using more.

Weapons Range Modifications by TL
TL 9101112131415
Range Multx1/3x2/3x1x4/3x5/3x2x7/3
Damage Roll Mods -2 per die-1 per die00+1 per die+2 per die

Skills

To represent skills, using CT/MT levels, or TNE Assets, or T4 Skill levels, see the following table:

Skill Effects (Mostly for Gunnery)
CT/MTTNET4Effect on To Hit Rolls, screen effects, etc
1<51-2Roll twice, take worse result
25-123-4no effect
3-413-155-6Roll twice, take better result
5-816-207-8Roll thrice, take best result
9+21+9+roll 4 times, take best result

[1] This is mass to volume for electronics and, essentially, most mechanical systems.

Legalalia

Traveller is a registered trademark of Far Future Enterprises. Full Thrust, More Thrust, and the Full Thrust Fleet Book are all trademarks of Ground Zero Games. Earth Force Sourcebook and the Babylon Project RPG are trademarks of Wireframe Productions and Chameleon Eclectic Publications. The use of these trademarked names is not intended to be, nor should it be construed as, challenge to the rightful holders/owners or their liscenced users, their trademarks, nor their copyrights.

Copyright ©2000, 2008, William F. Hostman. All Rights Reserved. Intended solely for the personal use of the reader.