HMS Unbeaten moored alongside a dock at Malta
|Builder:||Vickers Armstrong, Barrow-in-Furness|
|Laid down:||22 November 1939|
|Launched:||9 July 1940|
|Commissioned:||10 November 1940|
|Fate:||sunk 11 November 1942|
|Class and type:||U-class submarine|
|Length:||58.22 m (191 ft 0 in)|
|Beam:||4.90 m (16 ft 1 in)|
|Draught:||4.62 m (15 ft 2 in)|
HMS Unbeaten was a U-class submarine, of the second group of that class, built by Vickers Armstrong, Barrow-in-Furness. She was laid down on 22 November 1939 and was commissioned on 10 November 1940. So far she has been the only ship of the Royal Navy to bear the name Unbeaten.
Unbeaten spent much of her career operating in the Mediterranean, where she sank the Italian sailing vessel V 51 / Alfa, the Vichy-French merchant PLM 20, the Italian submarine Guglielmotti and the German submarine U-374. She also claimed to have sunk two sailing vessels with gunfire. Until today there is no confirmation from Italian or German sources as to the identity of the vessels attacked. It is also quite possible that the vessels were only damaged.
Unbeaten also lightly damaged the Italian merchant Vettor Pisani on 16 March 1942. She also unsuccessfully attacked the Italian merchant Silvio Scaroni, the Italian troop transport Esperia and a large Italian troop transport, thought to be either Oceania or Neptunia.
After a refit in Chatham, and subsequent workup, Unbeaten was attached to the Third Submarine Flotilla in Scotland. Having sailed from Holy Loch on her last patrol, Unbeaten completed Operation Bluestone, landing an agent in Spain near Bayona. She then completed her patrol in the Bay of Biscay and was returning to the UK when she went missing. It is believed that she was probably attacked and sunk in error by an Royal Air Force Wellington of No. 172 Squadron, Coastal Command in the Bay of Biscay on 11 November 1942 . She was lost with all hands.
Her first CO was Edward "Teddy" Woodward. Her second and last CO was Lt Donald Ogilvy Watson.
- See 'La Difesa del Trafico con L'Africa Settentrionale', the official Italian naval history. Vettor Pisani was lost to air attack on 24 July 1942. There is also no record in the official Admiralty naval staff history 'Submarines in the Mediterranean Vol. II
- HMS Unbeaten, Uboot.net
- Submarine losses 1904 to present day, RN Submarine Museum, Gosport
- 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.
- Smith, David (2012). Being Silent They Speak: The Story of a WWII Submarine Unbeaten. Plymouth: Stand Easy. ISBN 978-0-9573925-1-9. OCLC 53783010.