THE ROYAL Navy’s Southern Diving Unit Two (SDU2) has saved a 350-year-old shipwreck after a 1,000kg wartime mine was found inside it.
Civilian divers working with Historic England uncovered the weapon during an archaeological dive on the London, a secondrate ship-of-the-line that lies in two pieces off Southend Pier.
A complex six-day operation to remove the device, thought to be a Luftmine B – a large parachute mine dropped by the Luftwaffe – concluded with a controlled detonation on September 27. It involved nine agencies, including the eight-man Royal Navy team, HM Coastguard, Shoeburyness Ranges and the London Port Authorities.
The 17th century wreck was rediscovered in 2005 and has protected status, as the London is seen as a significant find and important to England’s maritime history.
The Luftmine B, also known as the GC, contained 697kg (1,535lb) of Hexamite explosive. It was described as being in “extremely good condition” and is one of the largest UXOs found in the Thames Estuary. The hazardous task was completed over 20 dives, taking place in poor conditions.
The divers spent 375 minutes beneath the waves and 27 hours at sea, carefully raising the mine and towing it 5 miles (8km) to a disposal site at Shoeburyness. Lieutenant Ben Brown RN, SDU2, stated: “The complexity of this task should not be underestimated…
With nil visibility underwater and significant tidal flow, the diving windows are extremely limited and all work on the ordnance must be done by touch.
“The deteriorating weather conditions also added another layer of complexity, and all whilst working next to one of the busiest shipping channels in the UK.
“However, these conditions are exactly what Royal Navy Clearance Divers are trained to work under.”
London was built across the water at Chatham, entering service in 1657 in the navy of the Commonwealth of England.
In 1660 she passed back into Royalist hands following the Restoration. On March 7, 1665, London was destroyed by an accidental explosion in her magazine. The death toll is unknown, but in his diary, Samuel Pepys makes reference to 24 people being blown clear with at least 300 perishing.