Freelance Traveller
The Republic of Thermidor is one of that loose halo of independent worlds "beyond the border" of an interstellar government, holding a "pocket empire" of two or three adjacent systems as colonies. Partially for defense in a frontier area and partially for prestige, the Sixteenth Republic maintains its own modest Navy of TL12 starships, giving them a "power projection" capability to send expeditionary forces for several parsecs outside their core system.
While the 300-ton, TL11 Torpilleur-class SDBs provide a powerful system defense, the Jump-capable missile corvette version left much to be desired - primarily a performance of only Jump-2 and 4-G instead of the Thermie fleet requirements of Jump-3 and 6-G. The 300-ton/Jump-2/4-G design was already tight; to achieve the required Jump-3/6-G performance while retaining the "mini-spinal" missile bay would require a larger ship.
These Grand-Torpilleurs are the result - a family of TL12 torpedo boats based on a scaled-up Torpilleur design. Like their smaller predecessors, they are intended to kill medium ships with one salvo or large ships in a "swarm" attack.
Grand-Torpilleur -- First Design:
The first attempt enlarged the hull to 500 tons, adding two hardpoints and turrets. Original plans were to enlarge the missile bay from 50 to 100 tons and add hull armor, but this proved to be impossible on 500 tons. While the performance requirements were met, the design otherwise had minimal improvements over the 300-tonner; after a small prototype/production run, this class was discontinued for Thermie service but was continued as an export model.
MBL Missile Corvette (TL12). 500 tons. Jump-3, 6-G. 210 tons fuel. Model/6. 14 staterooms, 4 emergency low berths. 1 50-ton missile bay, 4 triple turrets (BSB fit). 21 tons user-definable. Streamlined. 14 crew.
MCr 409.5 singly, MCr 368.5 in quantity; 18 months. Special Rules: Missile Bay.
Missile Corvette (Type MBL): Using a custom 500-ton hull, the Missile Corvette is a pure warship using a "mini-spinal" weapon bay to pack the maximum punch possible in a small hull. It mounts jump-drive H, maneuver-drive-Q, and power plant-Q, giving a performance of Jump-3 and 6-G acceleration. Fuel tankage for 210 tons supports the power plant and allows one Jump-3. Adjacent to the bridge is a computer Model/6. There are fourteen staterooms and four emergency low berths (for casualties). There is a 50-ton weapons bay in a "mini-spinal" configuration and four hardpoints; 54 tons are allocated for weapons and fire control. A 50-ton missile bay and four triple turrets are installed; each turret mounts two beam lasers and a sandcaster; magazines hold 21 sandcaster rounds per turret. User-definable capacity is 21 tons; the ship is streamlined.
The missile corvette requires a crew of 14: pilot, navigator, four engineers, medic, six gunners, and one extra, with a maximum life-support capacity of 28. The ship costs MCr 409.5 singly and MCr 368.5 in quantity at Tech Level 12, and takes 18 months to build.
Grand-Torpilleur -- Second Design:
Further enlarging the ship to 600 tons accommodated the 100-ton missile bay, with barely enough room to add minimal hull armor. The 100-ton bay retained the firepower-per-ton ratio of the 300-tonner while maintaining the Jump-3/6-G performance. This second design became the definitive TL12 missile corvette in Thermie service, and was copied extensively though never officially made for export.
MBLbis Missile Corvette (TL12). 600 tons. Jump-3, 6-G. 240 tons fuel. Model/6. 10 staterooms, 4 emergency low berths. 1 100-ton missile bay, 4 triple turrets (BSB fit). 37 tons user-definable space. Streamlined. 14 crew.
MCr 474.1 singly, MCr 426.1 in quantity; 18 months. Special rules: Missile Bay.
Missile Corvette (Type MBLbis): Using a custom 600-ton hull, the Missile Corvette is an enlarged version of the previous Grand-Torpilleur. It mounts jump drive-J, maneuver drive-T, and power plant-T, giving a performance of Jump-3 and 6-G acceleration. Fuel tankage for 240 tons supports the power plant and allows one Jump-3. Adjacent to the bridge is a computer Model/6. There are ten staterooms and four emergency low berths (for casualties). There is a 100-ton weapons bay in a "mini-spinal" configuration and two hardpoints; 104 tons are allocated for weapons and fire control. A 100-ton missile bay and four triple turrets are installed; each turret mounts two beam lasers and one sandcaster; magazines hold 21 sandcaster rounds per turret. User-definable capacity is 37 tons; the ship is streamlined.
The missile corvette requires a crew of 14: pilot, navigator, four engineers, medic, six gunners, and one extra (double-occupancy for four of the crew), with a maximum life-support capacity of 20. The ship costs MCr 474.1 singly and MCr 426.7 in quantity at Tech Level 12, and takes 18 months to build.
Variant: The hull may be armored to Armor-2, taking up all but one ton of the user-definable space for minimal protection. The resulting ship is extremely tight, and has next to no user-definable capacity.
MBA Armored Missile Corvette (TL12). 600 tons. Armor-2. Jump-3, 6-G. 240 tons fuel. Model/6. 10 staterooms, 4 emergency low berths. 1 100-ton missile bay, 4 triple turrets (BSB fit). 1 ton user-definable space. Streamlined. 14 crew.
MCr 492.3 singly, MCr 443.1 in quantity; 18 months. Special rules: Hull Armor, Missile Bay.
SDB Variant:
While the original 500-ton design was minimal for a Jump-capable missile corvette, it proved to be more than enough for an SDB. Without the tonnage for jump drive and jump fuel, the SDB variant had more than enough space to mount the 100-ton missile bay (giving it more firepower-per-ton than even the 300-ton SDB) plus maximized hull armor for its Tech Level. Production of the earlier 300-ton Torpilleur was soon phased out in favor of the new 500-tonners for Thermie service. Like the 600-ton corvette, these were never officially made for export.
SDB-ML System Defense Boat (TL12). 500 tons. Armor-12. No Jump, 6-G. 60 tons fuel. Model/6. 12 staterooms, 4 emergency low berths. 1 100-ton missile bay, 4 triple turrets (BSB fit). 44 tons user-definable. Streamlined. 12 crew.
MCr 533.2 singly, MCr 479.9 in quantity; 18 months. Special rules: Hull Armor, Missile Bay.
System Defense Boat -- Missile (Type SDB-ML). Using a custom 500-ton hull, the SDB-ML is a system defense boat variant of the MBL Missile Corvette using a "mini-spinal" weapon bay to pack the maximum punch possible in a small hull. It mounts maneuver drive-Q and power plant-Q, giving a performance of 6-G acceleration. Fuel tankage for 60 tons supports the power plant. Adjacent to the bridge is a computer Model/6. There are ten staterooms and four emergency low berths (for casualties). There is a 100-ton weapons bay in a "mini-spinal" configuration and four hardpoints; 104 tons are allocated for weapons and fire control. A 100-ton missile bay and four triple turrets are installed; each turret mounts two beam lasers and one sandcaster; magazines hold 21 sandcaster rounds per turret. User-definable capacity is 44 tons; the ship is streamlined. The hull is armored to Armor-12.
The SDB-ML requires a crew of 12: pilot, navigator, three engineers, medic, and six gunners, with a maximum life-support capacity of 24. The boat costs MCr 533.2 singly and MCr 479.9 in quantity at Tech Level 11, and takes 18 months to build.