HMS M1; HMS M2; HMS M3; M4 (not completed)
Traveling under the surface to search, track, and / or engage or reconnoiter areas.
Active patroling of vital waterways and maritime areas; can also serve as local deterrence against airborne and seaborne threats.
Serving in support (either firepower or material) of the main surface fleet in Blue Water environments.
2 x Vickers 12-cylinder diesel engines developing 2,400 horsepower with 4 x Electric motors generating 3,200 horsepower to 2 x Shafts astern.
(2,300 miles | 3,701 km)
1 knot = 1.15 mph; 1 nm = 1.15 mile; 1 nm = 1.85 km
1 x 12" (305mm) /40 caliber Mark IX artillery gun (50 x 305mm projectiles carried).
4 x 18" (450mm) torpedo tubes in the bow (four reloads carried).
1 x 3" (76mm) Mk II HA Anti-Aircraft (AA) deck gun.