Traveller Musings - Adding Armor to LBB2 Starships

Here's another Traveller house rule I've been thinking about. I originally wrote this down a few months ago, but since I have a blog to share it on now, I'm posting it here.

Some background:

In the Classic Traveller (CT) world, people are aware that there are sort of two different takes on Classic Traveller - the basic system described in the "Little Black Books" 1-3 (known as LBB1-3), and the expanded system that begins with "Book 4: Mercenary". It's a bit like the differences in Basic and Advanced Dungeons and Dragons back in the day, though LBB1-3 Traveller is not "capped" like Basic D&D was.

"Book 2 - Starships" laid out a universe not too different from the Age of Sail, where merchant ships and warships were sometimes interchangeable, no ships were the size of cities, and players in tramp freighters could sometimes hope to shoot their way past patrol craft. "Book 5 - High Guard" effectively ushered in the Age of the Dreadnought, and the Imperial Navy became a mighty fleet of gigantic, nearly indestructible Battlecruisers with spinal-mount meson cannons and bays full of particle accelerator cannons, the smallest of which was larger than any Bk2 ship possible. While very cool, it's not the same universe after Bk5 in my opinion.

To push the analogy to the breaking point, I'd like to be able to keep a "Book 2" universe, add some Ironclads, but not go all the way to Battleships.


I've seen many attempts to retrofit High Guard type armor rules into the Bk2 system, and many of them seem very workable. But none of them fit my personal "feel" criteria. This is my attempt to address that lack.

"Book 2" Starship Armor

Each hull section (main, engineering) may be armored separately. Each section's armor covers a certain range of hit locations (see below for details). If a hit hits an armored section, the armor absorbs the hit, but is then considered destroyed for that location. For example, if a ship with an armored engineering section takes a hit to the power plant, the hit will be discarded, but future hits to the power plant will be suffered as usual, as the armor there has been compromised.

Armor hits are repaired individually at a cost of 1% of the hull's cost per hit, and must be repaired at a C class or better shipyard. Note that it should never cost more than the armor's original cost to make repairs.

You can install armor multiple times, paying the price and displacement. Each new "layer" absorbs another hit.

For sake of exposition, here is the hit location table:

2 Powerplant
3 Maneuver
4 Jump (or Maneuver for non-starships)
5 Fuel
6 Hull
7 Hull
8 Hold
9 Computer
10 Turret
11 Turret
12 Critical

Main Section:

Armor costs 3% of the hull's normal cost, and the armor itself takes up 5% of the section's volume.

The armor covers locations 6, 7, 8 (Hull and hold - the most statistically likely locations, and the most economically oriented parts of a trading ship. Use the ship's floor plan to decide if the two hull hits should be crew/passenger or some other breakdown).

Engineering Section:

Armor costs 2% of the hull's normal cost, and the armor itself takes up 5% of the section's volume. Note that if the engineering section is larger than the main section, costs will need to be adjusted. Note that the smaller standard hulls generally do not have enough extra tonnage to contain the armor, so to armor the drives of a merchant ship, you would need a custom hull design.

The armor covers locations 2,3,4 (the drives).

Note that to armor the entire ship would cost 5% of the hull's cost, and would take 5% of the total ship's volume, split between the two sections.

[I based the armor costs off of Mongoose Traveller's SRD, so while this armor doesn't function like MgT armor, it costs the same.]

Advanced Ideas

You can buy higher tech armor materials, but you limit yourself to repairs at a starport of the appropriate tech level. Note that all armor takes up the same displacement, but the cost varies considerably. More rigid armors can cover harder-to-cover locations as well as provide better coverage in the normal locations.

Titanium Steel (TL 7+) The basic armor, costs 5% of the hull's cost (3% for main, 2% for engineering)

• absorbs first hit to (2,3,4,6,7,8)

Crystaliron (TL 10+) 4x more expensive

• absorbs first two hits to (2,3,4,6,7,8)
• absorbs first hit to (5,9) (fuel, computer)

Bonded Superdense( TL 14+) 10x more expensive than Titanium

• absorbs first three hits to (2,3,4,6,7,8)
• absorbs first two hits to (5,9)
• absorbs first hit to (10,11) (turrets)