OVERVIEW: The Mk 11 is an unguided, aerial-deployed depth charge designed by the United Kingdom for anti-submarine warfare. It is intended for shallow to medium-depth engagements and is released from helicopters or fixed-wing ASW aircraft.

DETAILS: The Mk 11 is a post–World War II British depth charge, weighing approximately 134 to 145 kg, with a length around 1.4 m and a diameter of 270 mm. It uses a steel body and a reinforced Mod 3 nose section to withstand high-velocity water entry. The charge is equipped with hydrostatic pistols to detonate at preset depths, typically up to 900 m. It was designed for use in maritime patrol and naval aviation operations.

FUNCTION: The Mk 11 is dropped onto sonar or MAD-detected submarine contacts, sinking to the designated depth before detonating. Its role is to inflict damage or neutralize enemy submarines operating in shallow water or littoral zones.

NOTE:
IOC: Post-1945 (Mk 11 base model), ~1950s (Mk 11 Mod 2/3)
Operators: United Kingdom
Platforms: Sea King HAS.6, Lynx HMA.8, Merlin HM.1/HM.2, Wildcat HMA.2

SOURCE:
Imperial War Museums: https://www.iwm.org.uk/collections/item/object/30020470 ; Jane’s Weapons: Naval ; British Aerospace Technical Sheets ; The National Archives (UK): https://discovery.nationalarchives.gov.uk/details/r/C4387816