Book 5: High Guard was one of the best splat books ever added to a game, in my opinion. Advanced character generation, advanced ship design, detailed yet streamlined space combat.
Hard to top and it might not have seen its equal in the 37 years since it came out.
Lots and lots of people use HG to build ships, but I also use it to look at the 'Domain Game' of Traveller (or as Traveller calls it, the Pocket Empires game).
Let's talk about what the shipbuilding charts in HG tell us about building a campaign setting for Classic Traveller looks like.
First, a quick glance at FTL travel with the Drive Tech Table:
You need to have Tech Level 9 to have any FTL ships and you don't get longer than 1 parsec until TL11+.
Impact: To have interstellar travel you must have worlds capable of at least maintaining and repairing TL9 jump drives. To have real strategic speed you have to have TL11+. This means TL9 and 10 civilizations will be very 'local' compared to higher techs.
Now let's look at Weapons and Defenses, starting with major weapons weapons, i.e., stuff that's big for starships:
At TL9 you have access to heavy bay Particle Accelerators (or PAs), PA spinal mounts, and heavy missile bays. TL10 adds heavy repulsor bays and bigger PA spinal mounts as well as some light bay weapon systems. TL11 is a big jump where you gain Meson spinal mounts.
Let's look at turrets:
It can be hard to see, but the heavier energy weapons aren't available until TL10+ and they get more powerful fairly rapidly.
Last in this section, screens;
You can't have nuclear dampers or meson screens until TL12+.
I am not going to post the huge combat charts showing the various target numbers to hit and then penetrate, but the end result is - until TL10+ missiles, especially nuclear missiles, dominate space combat because they are more likely to hit and penetrate. Repulsors eat up some of (ok - a lot of) the advantage of missiles at TL10 and TL11, but once nuclear dampers are added to the mix missiles are matched by energy weapons. If you track missile reloads in large scale, long-term space battles energy weapons can take the edge, especially at higher TLs.
Impact: Missiles rule until TL12. After TL12 ship-killer mesons spinal mounts appear.
Now it is time to talk about a rather odd fact or two. Here is the computer chart:
This chart is important because more powerful computers = bonuses to hit and penetrate with weapon fire. This chart is critical to world building because of ship size.
See that column that is headed'Ship'? That column is 'the hull tonnage size that requires that model of computer as a minimum'. In other words, that code is the largest ship hull available with that computer model. This means hull size is limited by tech level.
Here is the hull chart:
By cross-reference you can see that at TL9 maximum hull size is D, or 4,000 displacement tons while at TL12 maximum hull size is R, or 100,000 displacement tons.
There are some very interesting implications from this! For example, at TL9 the smallest PA spinal mount is 5,000 displacement tons while the largest possible space ship is 4,000 displacement tons. As a result, at TL9 PA spinal mounts are for planets, moons, etc., not ships. The most powerful weapon that can be put into a TL9 ship is a 100 ton missile bay with a weapon factor of 7. Next would be a PA bay or a total of 30 missile tube, both of which have a weapon factor of 7. A capitol ship for a TL9 navy might look like;
4,000d dt, Jump-1, Manuever-3
1 x 100 dt PA bay (factor 6)
10 x triple sand turrets (1 battery of factor 7)
10 x triple missile turrets (5 batteries of factor 3 each)
10 x triple beam turrets (5 batteries of weapon factor 4 each)
Armor factor 12
Agility 1 (emergency 3)
Computer factor 3
So while it has a relatively low agility it has fair survivability with the beam lasers capable of anti-missile fire and the sand to stop heavy energy attacks and decent armor.
On the other hand, TL12 is a big leap in capabilities. Ships get very big, meson spinal mounts, meson screens, and nuclear dampers are on the table, armor gets tougher, etc. The differences are pretty stark - the TL9 navy's capital ship isn't a match for a TL12 navy's frigate - the TL12 frigate would have Jump-2, heavier armor, better agility, and a more powerful computer in the same size hull. This means the higher TL ship chooses the range of engagement, hits more often, penetrates more often, gets hit less often, etc.
The Fun Lads Four refer having a more powerful computer in space combat "The Traveller Bless spell".
TL12+ capitol ships should be able to engage entire TL9 battle groups alone and prevail.
So how could a TL9 navy face a TL12 navy?
Two words - zergling rush.
The TL9 navy could put so many ships into play at so many locations that the TL12 navy would be forced to pick what it defends. With the TL12 navy pinned the TL9 navy could then swarm selected fleets, or even ships, with an overwhelming number of attackers. This depends on a few things, though:
1) They need to have that many hulls
2) They have to be able to lose a lot of hulls
3) They have to be willing to lose a lot of hulls
4) They must be committed to a long conflict
5) Their own economic and supply bases must be secure from counter-attack
That is a tough combo to pull off.
Impact: When doing world building within CT to achieve anything approaching parity between a TL( civilization and a TL12+ civilization the TL9 group must be much larger and have a lot more population and have well-defended manufacturing. If not the TL12+ group will be able to overwhelm the other at will.
Next time - how I used these elements to make my new CT campaign setting.