HMS Tetrarch (N77)
|Builder:||Vickers Armstrong, Barrow|
|Laid down:||24 August 1938|
|Launched:||14 November 1939|
|Commissioned:||15 February 1940|
|Fate:||sunk 2 November 1941|
|Class and type:||British T class submarine|
|Displacement:||1,090 tons surfaced
1,575 tons submerged
|Length:||275 ft (84 m)|
|Beam:||26 ft 6 in (8.08 m)|
|Draught:||16.3 ft (5.0 m)|
Twin diesel engines 2,500 hp (1.86 MW) each
|Speed:||15.25 knots (28.7 km/h) surfaced
9 knots (20 km/h) submerged
|Range:||4,500 nautical miles at 11 knots (8,330 km at 20 km/h) surfaced|
|Test depth:||300 ft (91 m) max|
|Armament:||6 internal forward-facing torpedo tubes
4 external forward-facing torpedo tubes
Tetrarch's first success came in May 1940 when she torpedoed and sank the German submarine chaser UJ B / Treff V in the Skagerrak. She also sunk the Danish fishing vessel Terieven and the German tanker Samland, and captured the Danish fishing vessel Emmanuel, which was taken to Leith as a prize.
Tetrarch was assigned to operate in the Mediterranean in late 1940. She sank the Italian merchants Snia Amba, Giovinezza and Citta di Bastia, the Italian tanker Persiano, the Italian sailing vessels V 72/Fratelli Garre, V 113/Francesco Garre and Nicita, and the Greek sailing vessel Panagiotis Kramottos. She also damaged the German merchant Yalova and claimed to have damaged a sailing vessel in the Aegean. Tetrarch also launched an unsuccessful attack on the Greek tanker Olympos.
Tetrach sailed from Malta on 26 October 1941 for a refit in Britain, via Gibraltar. She failed to arrive in Gibraltar on 2 November and was declared overdue. Her route passed through a known minefield. On Monday 27 she communicated with P34, which was in the same area. This was the last contact with the submarine. She is presumed lost to Italian mines off Capo Granditola, Sicily, Italy in late October 1941.
- Colledge, J. J.; Warlow, Ben (2006) . Ships of the Royal Navy: The Complete Record of all Fighting Ships of the Royal Navy (Rev. ed.). London: Chatham Publishing. ISBN 978-1-86176-281-8. OCLC 67375475.
- Hutchinson, Robert (2001). Jane's Submarines: War Beneath the Waves from 1776 to the Present Day. London: HarperCollins. ISBN 978-0-00-710558-8. OCLC 53783010.