Also known as: HMS Vanguard (1909)
Just before midnight on 9 July 1917, the anchorage at Scapa Flow was torn apart by a series of explosions so violent that debris rained down on ships anchored half a mile away. HMS Vanguard had blown up at her moorings. Of 845 men aboard, two survived. It remains the largest accidental loss of life the Royal Navy suffered in the entire twentieth century, and the Court of Enquiry traced the cause to an unintentional cordite explosion — unstable propellant stored in magazines where temperatures were poorly controlled. The wreck lies scattered across the seabed in 34 metres off the north coast of Flotta, so thoroughly destroyed by the blast that it bears little structural resemblance to the St Vincent-class dreadnought she once was. Like HMS Royal Oak, Vanguard is a designated war grave under the Protection of Military Remains Act 1986 and diving is forbidden. The recoverable dead lie in Lyness Royal Naval Cemetery on Hoy, within sight of the water that claimed them.
St Vincent-class dreadnought battleship. Armed with 5 twin 12-inch guns, 20 x 4-inch guns, 3 x 18-inch torpedo tubes. Speed 21 knots. Range 6,900 nm at 10 knots. Complement 753. At approximately 23:20 on 9 July 1917, while at anchor in Scapa Flow, she suffered catastrophic internal magazine explosions. 843 killed — only 2 survivors. Largest accidental loss of life in the Royal Navy during the 20th century. Court of Enquiry concluded an unintentional cordite explosion.
HMS Vanguard is a battleship wreck located off Orkney, United Kingdom at a depth of 34 metres. The vessel was lost due to internal explosion in 1917.
HMS Vanguard lies at approximately 34 metres depth, Off north coast of Flotta, Scapa Flow.
HMS Vanguard was lost due to internal explosion on 9 July 1917 during World War I — accidental loss, off Orkney, United Kingdom. 843 people lost their lives.
The best months to dive HMS Vanguard are May, June, July, August, September. Water temperature ranges from 6°C in winter to 14°C in summer.
HMS Vanguard is accessed by boat from Lyness, Orkney, United Kingdom. The wreck is a designated war grave.
| Month | Temp | Visibility | Access | Marine life |
|---|---|---|---|---|
| Jan | 6.0°C | 5.0m | poor | Low — winter conditions |
| Feb | 6.5°C | 5.0m | poor | Low — winter conditions |
| Mar | 7.0°C | 6.0m | poor | Low — winter conditions |
| Apr | 8.0°C | 8.0m | marginal | Moderate — season starting; seals present |
| May | 9.5°C | 10.0m | good | Moderate — seals, wrasse, lobster, soft corals |
| Jun | 11.0°C | 14.0m | good | High — seals, jellyfish, lobster, wrasse, soft corals, pollock shoals |
| Jul | 12.5°C | 18.0m | good | High — seals, jellyfish, lobster, wrasse, soft corals, pollock shoals |
| Aug | 14.0°C | 18.0m | good | High — seals, jellyfish, lobster, wrasse, soft corals, pollock shoals |
| Sep | 13.0°C | 14.0m | good | Good — seals, lobster, wrasse, soft corals |
| Oct | 11.0°C | 9.0m | marginal | Good — seals, lobster, wrasse, soft corals |
| Nov | 8.5°C | 6.0m | poor | Low — winter conditions |
| Dec | 7.0°C | 5.0m | poor | Low — winter conditions |
3 evidence records from 3 sources.
St Vincent-class. Length 536 ft. 5 twin 12-inch guns. 843 killed. Cordite explosion. Only 2 survivors.
St Vincent-class dreadnought. Internal magazine explosion 9 July 1917. 843 killed, 2 survivors. Largest accidental RN loss of 20th century.
Designated Controlled Site under Protection of Military Remains Act 1986. War grave since 1984.
Off north coast of Flotta, Scapa Flow