OVERVIEW: The L4 is a French heavy, surface-launched anti-submarine warfare (ASW) torpedo introduced in 1964. It was deployed from shipboard missile systems such as Malafon to engage submerged submarines.

DETAILS: The L4 was developed by France as a 533 mm diameter heavyweight ASW torpedo to serve as the terminal payload for the Malafon missile system. It features an electric propulsion system and active acoustic homing, allowing it to search for and pursue submarines after water entry. The torpedo carries a 104 kg high-explosive warhead and has a maximum speed of 30 knots, a range of 5.5 km, and an operational depth of around 300 meters. It provided surface warships with standoff ASW capability during the Cold War and was eventually replaced by more advanced systems.

TYPE: Heavyweight anti-submarine torpedo

FUNCTION: After being delivered by the Malafon missile from surface warships, the L4 enters the water and begins a programmed circular search using active acoustic homing to locate submarines. Once a target is acquired, it homes in and detonates upon impact or proximity.

NOTE:
IOC: 1964 (L4)
Manufacturer: DTCN (France)
Operators: France, Bangladesh
Platforms: Malafon-equipped warships (e.g., La Galissonnière-class)

SOURCE: Wikipedia: https://en.wikipedia.org/wiki/Torpille_DTCN_L4 ; Wikipedia: https://en.wikipedia.org/wiki/Malafon ; GlobalSecurity: https://www.globalsecurity.org/military/world/europe/leygues.htm