19/06/2026
A demonstration of the Hedgehog anti-submarine depth-bomb discharger during the Second World War.
Developed by the Royal Navy during the Second World War, the Hedgehog consisted of up to 24 mortars fired at U-boats. This clip comes from a 1943 instructional film on the Type 144 Asdic sonar system, which was developed specifically for weapons like the Hedgehog, which fired ahead of the attacking vessel.
You can find the film in full on our website: https://bit.ly/4fR5pqK
Film: IWM ADM 179