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Hmmm,
I'm having a lot of trouble pinning down where this runaway fuel addition is happening. I'll keep search, but if you could let me know at what point it suddenly appears at it would be really helpful.
I'll see if I can recreate it, but i discovered it in 0.1.3 and you have changed the fuel allocation in 0.1.4, so...
 
R-Drives as written are an alternative to M-Drives that use solid fuel, the calculations in the combat thrust section comes straight from Page 18 but it looks like they aren't calculating properly!
High Burn Thrusters are Reaction drives, it's just a question of nomenclature.
High Guard, p45:
HIGH-BURN THRUSTER
A high-burn thruster is an auxiliary chemical rocket designed to give a temporary speed boost to a ship. This is done by adding a reaction drive whose Thrust is cumulative with that of the ship’s regular drive system.
Starship Operator's Manual, p94:
When reaction drives are present on a starship, it is most often due to one of three reasons, the first two of which are more common among ships designed for combat. First, reaction and manoeuvre drives have a maximum performance generally limited by TL but these are separate limits. Having both systems allows a ship to accelerate at the sum of the drives’ performances, achieving much greater acceleration than is possible with either drive alone.


It should be 16 X 10 X 10 - It looks like I have accidentally added together all of the fuel tanks and made them available as thruster fuel, maybe? (that math doesnt explain it properly either, but it's something like that anyway - I'll sort it out).
I think you took max(thrust) × max(fuel duration) = thrust points, so reaction drive thrust × power plant duration...
 
I don't agree with this interpretation.

"Making a bridge detachable adds +50% to its cost"

The rules implication of this for me is that you can make any bridge type detachable as an additional option - I can have a "Smaller Bridge" that is also Detachable, I can have a "Command Bridge" that is also detachable.

I decide what bridge type I want, add 50% cost and 20% weight and now it is also detachable.
Yes, perhaps, but that clashes with the Detachable Bridge table...
Skärmavbild 2025-10-21 kl. 10.18.28.png

A Detachable Bridge for a 500 Dt ship should probably be 30 Dt (+20%?), and cost 500 Dt / 100 Dt × MCr0.5 × 150% = MCr 3.75, 50% more than a regular bridge.

A Small Detachable Bridge would be the next smaller size on the Detachable Bridge table, 15 Dt (+20%?) and cost 500 Dt / 100 Dt × MCr0.25 × 150% = MCr 1.875, 50% more than a regular small bridge.

I believe... Check with @MongooseMatt?


The earlier version of High Guard, from 2016, was clearer:
Skärmavbild 2025-10-21 kl. 10.09.45.png
 
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There is no smaller bridge than 3 Dt, a small bridge on a 35 Dt small craft is still 3 Dt, the same size as the regular bridge, even if cheaper:

Bridge, 3 Dt?
Skärmavbild 2025-10-21 kl. 10.22.54.png

Small Bridge 1 Dt?
Skärmavbild 2025-10-21 kl. 10.23.05.png
 
When I installed weapons on the medium fighter, hence Power, hence larger power plant, hence recalculated fuel:
Skärmavbild 2025-10-21 kl. 10.37.10.png
Skärmavbild 2025-10-21 kl. 10.37.37.png


Finalise says:
Skärmavbild 2025-10-21 kl. 10.39.55.png

Summary:
Skärmavbild 2025-10-21 kl. 10.41.10.png
Skärmavbild 2025-10-21 kl. 10.41.20.png

If I go back to the Power or Fuel tab, then fuel is recalculated correctly.


Remove the weapons, and it's back...
Skärmavbild 2025-10-21 kl. 10.45.17.png

Despite the decreased power plant, it's the same amount of fuel allocated:
Skärmavbild 2025-10-21 kl. 10.46.25.png
 
Let's build a Patrol Corvette (HG, p187):

Allocate hull and drives, fuel is OK:
Skärmavbild 2025-10-21 kl. 10.52.23.png

Install some weapons, fuel is OK:
Skärmavbild 2025-10-21 kl. 10.56.02.png

Visit the Power and Fuel tab without changing any values:
Skärmavbild 2025-10-21 kl. 11.01.53.png
Fuel is now reserved for three jumps à 3 Pc each. Probably not intended?
 
Add a reaction drive:
Skärmavbild 2025-10-21 kl. 11.12.11.png
Skärmavbild 2025-10-21 kl. 11.12.23.png
Skärmavbild 2025-10-21 kl. 11.12.30.png


An extra 20000 Dt fuel is allocated...
Skärmavbild 2025-10-21 kl. 11.13.58.png

Go to the Fuel tab and it's gone (Power tab changed nothing):
Skärmavbild 2025-10-21 kl. 11.16.09.png

Add a turret, and it's back:
Skärmavbild 2025-10-21 kl. 11.18.26.png

So, the fuel bug seems to be connected to automatic fuel calculation while having a reaction drive?
 
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Torpedoes are three per Dt, 10 torpedoes should be 3.33 Dt.
Missiles are not 1 Dt each, but 1 Dt for 12, 10 missiles should be 0.83 Dt:
Sand canisters are 20 per Dt, so correct.
Skärmavbild 2025-10-21 kl. 11.24.28.png
 
Enhancement request:
Recalculate on 'Enter' or 'Return' in all input fields.

Sorry, I'm spreadsheet damaged, recalculate on 'Tab' or mouse click feels unnatural...
 
Thrust points are calculated using hours of fuel as weeks of endurance:

1 h reaction fuel => 1 week = 168 h endurance:
Skärmavbild 2025-10-21 kl. 12.01.21.png


2 h reaction fuel => 2 weeks = 336 h endurance:
Skärmavbild 2025-10-21 kl. 12.01.34.png
 
Version 0.1.5:
Let's build a Kinunir (HG,p215):

Skärmavbild 2025-10-21 kl. 12.19.49.png

A standard bridge is 40 Dton and MCr 6.
Holographic Controls are an additinal 25% = MCr 6 × 25% = MCr 1.5 (and no extra power).

The detachable bridge should calculate cost based on hull size, not bridge size, so (1200/100, round up) × MCr 0.5 × 150% = MCr 9.
 
If we change from commercial to military crew, the number of crew and allocated staterooms change, but total consumed tonnage does not change:

Commercial Crew: 24 in 24 staterooms, total tonnage 1079 Dton:
Skärmavbild 2025-10-21 kl. 12.52.34.png
Skärmavbild 2025-10-21 kl. 12.52.46.png


Military Crew: 29 in 24 staterooms (of 29 needed), total tonnage 1079 Dton.
Skärmavbild 2025-10-21 kl. 12.53.24.png

Skärmavbild 2025-10-21 kl. 12.53.33.png
 
Crew calculations (docking spaces allocated, but no craft allocated):
Skärmavbild 2025-10-21 kl. 13.05.52.png
Engineers: 8, should be 7 = (50 + 130 + 44) / 35, round up.
Maintenance: 3, should be 2 = 1200 / 500, round down.
Gunners: 8, should be 20 = 2 × (#turrets + #barbettes + #screens)
Administrator: 2, should be 1 = 1200 / 1000, round down.
Officer: 0, should be crew/10, round down.

Rounding is not generally specified in the rules, but implicit from the example ships in HG.

In general the crew specified in LBB2 50 years ago are rounded up, the new crew categories are rounded down, I believe... Small ship copied from Classic Traveller often use the same crew as was specified in CT. It would be nice if the software recreated that...
 
Recommended Common Areas should presumably be calculated on allocated accommodations, not on crew.

Skärmavbild 2025-10-21 kl. 13.31.01.png

Here 60 Dt Common Areas are allocated for 25 staterooms and 35 barracks. Common Areas are calculated before barracks are considered.

Skärmavbild 2025-10-21 kl. 13.34.16.png
By default I would allocate 25% of actually allocated accommodations, so (25×4 + 35) × 25% = 33.75 Dt.

The Kinunir allocates 20 staterooms, 35 barracks, and 29 Dt [≈(80+35)×25%] common areas:
Skärmavbild 2025-10-21 kl. 13.47.57.png
Skärmavbild 2025-10-21 kl. 13.48.03.png


Note that barracks are only allowed for troops and basic passengers, not crew. Should be checked?


By Traveller convention, troops are not crew, but more permanent passengers, so should be included in Medic calculations, but not Officer requirement, see e.g. HG,p242.
 
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