Well I wanted to enter in two more canon designs which really shed more light on the state of nautical forces in different eras of BattleTech. The Sea Skimmer as Irose pointed out is a design which I over looked when putting together my original list however the first paragraph from the overview says a ton.
After the Exodus era the wet navy all but vanished. Each newly colonized planet had only one government and so had no need to build a wet navy to sink another government's wet navy. Nor could a colony world hide behind an ocean when invaded from space.
It would seem that the nautical forces of the InnerSphere were a luxury of the Star League era and when war came they were disbanded. Likely cannibalized into more useful endeavors rather than destroyed I would think. Troopers being mobilized as infantry with weapons and ammo going to other military arms.
It all really adds up if you read the canon design lead ins. See the second canon vehicle i missed the Mauna Kea Command Vessel. It lays out the role of the wet navy which Ice asked about earlier essentially a pirate hunting force deployed against raiders in economic vital yet remote ocean locations. Makes sense I guess cause Mechs and AeroFighters can really smash any wet naval force.
Factor in the difficult maintenance of sea going craft along with more pressing military concerns and you get the fringe military wet navy. Some worlds have more important ocean real estate to cover and deploy larger forces but that is the exception and not the rule.
Let me update that list once again.
Naval Surface VehiclesSea Skimmer Hydrofoil (TRO 3026 pg 24-25 - 25 tons - Lyran introduced 2867)
Silverfin / Silverback Coastal Cutter (TRO Vehicle Annex pg 160-161 - 40 tons - Terran Alliance introduced 2302)
Monitor Naval Vessel (TRO 3026 pg 72-73 - 75 tons - Kurita introduced late 2900s?)
Mauna Kea Command Vessel (TRO 3075 pg 256-257 - 85 tons - Marik introduced 2463)
Naval Submersible VehiclesManta Attack Submarine (TRO 3085 Supplemental pg 18-19 - 50 tons - Star League introduced 2600s?)
Sea Wolf Fast Attack Submarine (Project Phoenix pg 162-164 - 50 tons - Star League introduced 2743)
Nautilus Ballistic Missile Submarine (Project Phoenix pg 164-166 - 100 tons - Star League introduced 2743)
Neptune Submarine (TRO 3026 pg 96-97 - 100 tons - Davion introduced 2950)
Moray Attack Submarine (140 tons) (TRO 3085 Supplemental pg 18-19 - 50 tons - Star League introduced 2600s?)
Naval (Surface) Vessel Support VehiclesCliona class Frigate (TRO Vehicle Annex pg 164-165 - ?? tons - Lyrans introduced ??)
Rapier class Patrol Frigate (HDHB pg 201 - 8,500 tons - Davion introduced 2950s)
Andryusha class Bombardment Frigate (HLHB pg 164 - 8,500 tons - Capellan introduced 3065)
Meabh class Heavy Cruiser (TRO Vehicle Annex pg 164-165 - 10,000 tons - Lyran introduced 2807*)
Lucius Zhao class Escort Carrier (TRO Vehicle Annex pg 166-167 - 15,000 tons - Capellan introduced ??)
Jormungand class Bluewater Cruiser (HSHB pg 171 - 60,000 tons - Lyran introduced 2902)
Luftenburg class Supercarrier (TRO Vehicle Annex pg 166-167 - 100,000 tons - Lyran introduced 2741)
Naval (Submarine) Vessel Support VehiclesTriton class Missile Submarine (TRO Vehicle Annex pg 176-177 - 12,000 tons - Kurita introduced 3059)
Wyrm class Submersible Mega-fortress (JHS Terra pg 188-189 - 22,726.5 tons - WoB 3072)
Lysander class Carrier Submarine (TRO Vehicle Annex pg 178-179 - 26,000 tons - Kurita introduced late 3040s)
Argo class Submersible Carrier (HMHB pg 166 - 30,000 tons - Marik introduced
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