1,768 tons (
Porpoise), 1,810 tons (others) surfaced
2,035 tons ( Porpoise), 2,157 tons (others) submerged
289 ft (88 m) (
Porpoise), 293 ft (89 m) (others)
29 ft 10 in (9.09 m) (
Porpoise), 25 ft 6 in (7.77 m) (others)
15 ft 10 in (4.83 m) (
Porpoise), 16 ft 10 in (5.13 m) (others)
2 shaft, Diesel (3300 hp) plus electric (1630 hp)
15.5 knots (28.7 km/h; 17.8 mph) surfaced
8.75 knots (16.21 km/h; 10.07 mph) submerged
6 × 21 in torpedo tubes (bow)
1 × QF 4-inch (101.6 mm) Mk XII deck gun
submarines were a group of Grampus-class minelaying submarines built for the Royal Navy in the late 1930s. These boats are sometimes referred to as the from the single prototype, HMS Porpoise class Porpoise built in 1932. Five boats to a modified design were built between 1936 and 1938. The ships were all named after marine mammals.
The mines were stored in a special "gallery" with a conveyor belt built into the outer casing as pioneered by the converted
M-class submarine HMS . These boats were of a M3 saddle tank type.
Service [ edit ]
They were used extensively in the
Mediterranean, particularly to supply the besieged island of Malta in a service nicknamed the "magic carpet".
Only one, HMS
Rorqual, survived the war.
Boats in class [ edit ]
See also [ edit ]
Media related to Grampus-class submarine at Wikimedia Commons
References [ edit ]
Coordinates: 37°05′N 17°30′E / 37.083°N 17.500°E