Grampus-class submarine

Class overview
NameGrampus class
Operators Royal Navy  Kriegsmarine
Preceded byRiver class
Succeeded byT class
In commission1933—1945
Completed6
Lost5
Retired1
General characteristics
TypeSubmarine
Displacement
  • 1,810 tons surfaced
  • 2,157 tons submerged
Length293 ft (89 m)
Beam25 ft 6 in (7.77 m)
Draught16 ft 10 in (5.13 m)
Propulsion2 shaft, diesel (3,300 hp; 2,500 kW) plus electric (1,630 hp; 1,220 kW)
Speed
  • 15.5 knots (28.7 km/h; 17.8 mph) surfaced
  • 8.75 knots (16.21 km/h; 10.07 mph) submerged
Complement59
Armament

The Grampus-class submarines were a group of minelaying submarines built for the Royal Navy in the late 1930s. These boats are sometimes referred to as the Porpoise class from the single prototype, HMS Porpoise built in 1932. Five boats to a modified design were built between 1936 and 1938. The ships were all named after marine mammals.