Monday, January 18, 2021

Local Defense Forces and System Defense Boats

I was posted to the Sig-Delt-885 for a couple of years. Good little pig boat, an old Sentry class that we called the Salli Dell. And a good crew of spacers, though we mostly pulled duty in the outer system. Caught a couple of smugglers, chased off a few pirates. Even got fired on once by a twitchy Aslan trader. But mostly just got really, really good at Dingir Hold’em.

In Traveller, most worlds with a Population Level of 6+ and a Technology Level of 7+ will have some sort of local naval force for the defense of the system, as well as a base to support such forces. At the lower end of the tech levels these forces will be capable of interplanetary but not interstellar flight.

Determining Local Defense Forces

The GDW designers of the Fifth Frontier War boardgame (1981) used a simple matrix of Population and TL to determine the number of system defense craft protecting different systems. This matrix was reverse-engineered by different Traveller fans and eventually published in the T4 supplement Imperial Squadrons (1997) as a table of “SDB Squadrons.”

Chris Thrash developed a handy analysis of “Military Forces and Spending in Classic Traveller,” in which he suggests that the median Imperial system defense craft is about 2,000 tons in size, but might range from as small as a 100-ton small system defense boat (SDB) all the way up to a 50,000-ton monitor.

Thrash’s analysis also suggests that we could introduce some variability to the Imperial Squadrons table. Instead of determining a number of system defense squadrons, we can generate a total tonnage for the local defense force, which can then be assigned as desired by the referee.

First, roll Flux (1D - 1D) and consult the following table to determine the base tonnage of system defense craft. Then multiply this base tonnage by the appropriate system defense factor to get a total tonnage of defense forces.

Base Tonnages
FluxTonnage
-5400
-4700
-31,000
-21,400
-11,700
02,000
13,600
25,200
36,800
48,400
510,000
System Defense Factors
TLPopulation
6789A
71/101550500
81/101550500
91/101101001,000
A1/101101001,000
B1/101121201,200
C1/101121201,200
D1/101151501,500
E1/101151501,500
F1/52202002,000

For example, Wicker (Magyar 2728 A541843-C) has a system defense factor of 12. Rolling a Flux of 3 generates a base tonnage of 6,800. Multiplied by 12 produces a total defense tonnage of 81,600. This might represent 200 400-ton Guardian-class SDBs, possibly divided into four wings. The leftover 1,600 tons might be spent on squadron of 32 50-ton heavy fighters. Or perhaps Wicker could use some portion of this tonnage on a couple of light monitors with spinal weapons.

In my campaign the Wicker system also has a notable secondary world, Marston (F4346AB-9), which has just enough of a population base to support its own local naval forces. Rolling a Flux of 5 generates a base tonnage of 10,000, which multiplied by a system defense factor of 1/10 produces a total tonnage of 1,000. This might represent a single squadron of twenty 50-ton heavy fighters.

Wicker is a subsector capital on the edge of Confederation space and therefore a priority target for the Solomani. The primary challenge for defense planners is that the Wicker system has too many places it needs to protect: in addition to the mainworld and Marston, there are four gas giants. Although GURPS Traveller: Starships suggests that “it usually takes fewer than 20–30 SDBs to fully cover a single gas giant” (109), that’s a lot of real estate for 82,600 tons of system defense craft, which suggests the Imperial Navy probably maintains a guardship if not a full squadron on station in the system. Given that Wicker is the subsector headquarters for the Unified Army of Fugue, an Imperial squadron would probably be an AssaultRon.

Bases

It’s important to note that the defense forces generated above are under the control of the local system and not the Imperial Navy (Imperial Encyclopedia 32). And as Thrash notes, “All worlds with local planetary and colonial naval forces have their own bases to support them (Supp. 3, p. 40). These are not depicted on the standard subsector maps.”

If an Imperial Naval Base is present, it will command its own defense forces. Based on GURPS Traveller: Starports (2000), we can also develop tonnage estimates for the Imperial Navy bases that do appear on subsector maps:

Imperial Navy Base Defenses
FluxTypical
Base
Subsector
Fleet HQ
Sector
Fleet HQ
-54,00020,000200,000
-44,00022,000220,000
-34,50024,000240,000
-25,00026,000260,000
-15,50028,000280,000
06,00030,000300,000
16,50032,000320,000
27,00034,000340,000
37,50036,000360,000
48,00038,000380,000
58,00040,000400,000

The resulting tonnages may be a bit low for particularly important or strategic systems such as subsector capitals or depots. (A few monitors eat up a lot of tonnage!) I might consider multiplying the tonnage by up to the mainworld”s Importance rating. These system defense craft will generally be TL14 and 15 heavy vessels and will likely include multiple monitors with spinal weapon systems. An additional 1/8th of this tonnage will be available in fighter support.

For example, the naval base at Asorret (Magyar 2923 B403866-B ) is the headquarters of the Imperial 96th Fleet. Rolling a Flux of 4 indicates base defense forces of 36,000 tons. This might consist of five 6,000-ton light monitors, 30 200-ton Serpent-class SDBs, and 90 Rampart-class heavy fighters. And with an Importance rating of 2, these defenses might be as much as double these figures.

System Defense Boats

A 400-ton, TL15 SDB, typically used by the Imperial Navy for defense of sensitive facilities.

SDBs are one of the most common types of ships encountered by Travellers. In Classic Traveller, the iconic, TL12 400-ton Guardian-class SDB is detailed in Traders and Gunboats (1980) with additional information in Journal of the Travellers’ Aid Society #9 (1981). As both sources note, “A wide variety of system defense boats exist, ranging in tonnage from 100 to 1,000 tons, and in tech level from 8 to 15 and above.” The MT Imperial Encyclopedia (1987) increases this range from 100 to 5,000 tons.

This variation is certainly borne out by a quick survey of Traveller editions. In general, there are two archetypes that recur again and again: a boxy, 400-ton SDB similar to the Guardian-class, and a torpedo-shaped 200-ton SDB exemplified in CT Fighting Ships (1981); this is designated the Viper-class by Power Projection: Fleet.

We have canonical examples of the 400-ton SDB at every tech level from 11 to 15. Different editions assign different class names to these vessels. And given that these boats are notable for being readily modified with different armaments and configurations, the situation is probably confusing to inhabitants of the Third Imperium: in addition to Guardian, we have Sentry (TNE) and Dragon (GURPS and Hero). TNE also has a Shugukan-class, which I think is supposed to be Vilani for “Dragon.”

The TL11 Sentry is presumably a predecessor of the TL12 Guardian, and the Dragon (which might be TL13) is described as a “slight improvement on the earlier Guardian” (GT:Deck Plans 6). Further, we know that as of 1116 or so that Dragons “are still found in the Imperial Navy, but they have largely been replaced by more modern craft” (GURPS Traveller, 2nd edition). This might be the TL15 SDB statted out in the MegaTraveller Imperial Encyclopedia, which the MT Starship Operator’s Manual names Dragon (sigh) in the “Relative Size Chart” (58).

In any case, Mongoose Traveller 2e High Guard (2017) has designs for the two SDB archetypes: a TL15, 200-ton and a TL13, 400-ton boat. Because Magyar sector has a generally depressed tech level (no world exceeds TL14) and was once part of the Solomani Confederation, it seems more likely to harbor more examples of older, Solomani-influenced SDB designs.

Three canonical designs seem likely candidates: (1) the Solomani 300-ton “standard” SDB from Fighting Ships of the Solomani (2009), (2) the 400-ton Sentry-class from Assignment: Vigilante (1992), and (3) the 800-ton Farnez-class from T20 Fighting Ships (2003). All three are likely to be found on both sides of the Imperial/Confederation border in Magyar.

Standard Solomani SDB (SD-CS60). 300 tons (streamlined hull), 6g, no jump capability, TL-13, Model 7/fib. 9 tons fuel. 13 crew. 3 hardpoints. 0 tons cargo. MCr196.

Sentry-class SDB (SD-DS50). 400 tons (streamlined hull), 5g, no jump capability, TL-11, Model 5/fib. 16 tons fuel. 17 crew. 4 hardpoints. 74 tons cargo. MCr199.

Farnez-class SDB (SD-HS40). 800 tons (streamlined hull), 4g, no jump capability, TL-11, Model 5/fib. 24 tons fuel. 28 crew. 8 hardpoints. 57 tons cargo. MCr341.

Mongoose Traveller Designs

Since I have been playing with 2e High Guard, I wanted to try my hand at converting these three SDBs. Probably the most notable thing I discovered was that, without having to include a Jump drive and the attendant fuel tanks, you can end up with a lot of dead space—even after maxing out the armor and maneuver drives. (Most of the canonical examples had relatively low accelerations compared to what I ended up with in MgT.) Further, the number of hard points limits the number of weapons you can add: in many cases, I used small bays or barbettes instead of turrets in order to use up excess tonnage.

Standard Solomani System Defense Boat

The standard Solomani system defense boat is the 300-ton “standard” boat, a design that reaches back to before the Solomani Rim War. The standard boat is still built throughout the Confederation, with many examples in Magyar on both sides of the border.

Hull Points 132

Crew Captain, Pilot x3, Engineer, Maintenance, Medic, Gunner x6

Maintenance Cost MCr0.0163 per month

Purchase Cost MCr196

Standard Solomani SDB
TL13 TonsCosts (MCr)
Hull300 tons, Streamlined-18
 Reinforced-9
ArmorCrystaliron, Armor:134918
 Radiation Shielding-7.5
M-DriveThrust 61836
Power PlantFusion (TL12), Power 3602424
Fuel Tanks12 weeks operation9-
Bridge 201.5
ComputerCore 25/fib-15
SensorsImproved (Extended Arrays)912.9
 Countermeasures Suite24
 Enhanced Signal Processing28
WeaponsSmall Bays (fusion) x210016
 Barbette (missile) x154
AmmunitionMissile Storage (60 missiles)5-
Armored BulkheadsPower Plant2.40.48
 Maneuver Drive1.80.36
 Fuel0.90.18
 Bridge20.4
SystemsFuel Processor (10 tons/day)10.05
 Medical Bay x142
StateroomsStandard x9364.5
SoftwareManeuver/0--
 Intellect-1
 Evade/3-3
 Fire Control/5-10
 Library--
Common Areas81
Cargo0-

Sentry-class System Defense Boat

The Sentry-class SDBs were first built by a technical consortium on Dingir, prior to its reabsorption into the Third Imperium. The particle beam weapons package reflects an emphasis on reduced logistical requirements; missile resupply problems cannot affect the Sentry’s offensive punch. An official IDP (Imperial data package) design since 434, vessels of this class may be found in planetary navies of this tech level throughout the Imperium and beyond.

Hull Points 176

Crew Captain, Officer, Pilot x3, Engineer x2, Maintenance, Medic, Gunner x8

Maintenance Cost MCr.0166 per month

Purchase Cost MCr199

Sentry SDB
TL11 TonsCosts (MCr)
Hull400 tons, Streamlined-24
 Reinforced-12
ArmorCrystaliron, Armor:115520
 Radiation Shielding-10
M-DriveThrust 52040
Power PlantFusion (TL8), Power 3503518
Fuel Tanks16 weeks operation16-
Bridge 202
ComputerCore 15/fib-3
SensorsMilitary Grade24.1
 Improved Signal Processing14
WeaponsSmall Bays (particle beam) x210040
 Triple Turret (sandcaster) x223.5
AmmunitionSandcaster Barrels (120 barrels)6-
Armored BulkheadsPower Plant3.50.72
 Maneuver Drive20.4
 Fuel1.60.32
 Bridge20.4
SystemsFuel Processor (20 tons/day)10.05
 Medical Bay42
StateroomsStandard x11445.5
SoftwareManeuver/0--
 Intellect-1
 Evade/2-2
 Fire Control/3-6
 Library--
Common Areas111.1
Cargo74-

Farnez-class System Defense Boat

The Farnez class of SDB is typical of the lower technology end of system defense. The design predates the Solomani Rim War, when it was still being produced by the Imperial Navy and many lower tech worlds throughout the Imperium. At 800 displacement tons the Farnez is larger than many standard SDBs yet is still effective at system defense, and continues to see use in the planetary navies of Magyar sector.

Hull Points 352

Crew Captain, Officer x2, Pilot x3, Engineer x2, Maintenance x2, Medic, Gunner x16, Administrator

Maintenance Cost MCr.0284 per month

Purchase Cost MCr341

Farnez SDB
TL11 TonsCosts (MCr)
Hull800 tons, Streamlined-48
 Reinforced-24
ArmorCrystaliron, Armor:1111040
 Radiation Shielding-20
M-DriveThrust 43264
Power PlantFusion (TL8), Power 5405427
Fuel Tanks16 weeks operation24-
Bridge 204
ComputerCore 15/fib-3
SensorsMilitary Grade24.1
 Improved Signal Processing14
WeaponsSmall Bays (missile) x630072
 Triple Turret (beam laser) x225
AmmunitionMissile Storage (960 missiles)80-
Armored BulkheadsPower Plant5.41.1
 Maneuver Drive3.20.64
 Fuel2.40.48
 Bridge20.4
SystemsMedical Bay x142
StateroomsStandard x15607.5
 High x3182.4
SoftwareManeuver/0--
 Intellect-1
 Evade/2-2
 Fire Control/3-6
 Library--
Common Areas23.32.3
Cargo57-

Copyright Information

The Traveller game in all forms is owned by Far Future Enterprises. Copyright © 1977 – 2021 Far Future Enterprises. Traveller is a registered trademark of Far Future Enterprises. Far Future permits web sites and fanzines for this game, provided it contains this notice, that Far Future is notified, and subject to a withdrawal of permission on 90 days notice. The contents of this site are for personal, non-commercial use only. Any use of Far Future Enterprises’s copyrighted material or trademarks anywhere on this web site and its files should not be viewed as a challenge to those copyrights or trademarks. In addition, any program/articles/file on this site cannot be republished or distributed without the consent of the author who contributed it.

Materials produced by Digest Group Publications (DGP) are copyright © Roger Sanger. Any use of Digest Group Publications’ copyrighted material or trademarks anywhere on this Web site and its files should not be viewed as a challenge to those copyrights. Usage is intended to follow the guidelines announced by Roger Sanger on the Traveller Mailing List for preserving the overall Traveller milieu.

No comments:

Post a Comment