MK 54 Lightweight Torpedo

The Mark 54 was co-developed by Raytheon Integrated Defense Systems and the U.S. Navy under the U.S. Navy's Lightweight Hybrid Torpedo program in response to perceived problems with the extant Mark 50 and Mark 46 torpedoes. The Mk 50, having been developed to counter very high performance nuclear submarines such as the Soviet Alfa class, was seen as too expensive to use against relatively slow conventional submarines. The older Mk 46, designed for open-ocean use, performed poorly in the littoral areas, where the Navy envisioned itself likely to operate in the future.

The Mk 54 was created by combining the homing portion of the Mk 50 and the warhead and propulsion sections of the Mk 46, improved for better performance in shallow water, and with the addition of commercial off-the-shelf (COTS) technology to further reduce costs. It shares much of the software and computer hardware of the Mk 48 ADCAP heavy torpedo, based around a custom PowerPC 603e microprocessor.

The Mk 54 can be fired from surface ships via the Mark 32 surface vessel torpedo tubes or the vertical launch anti-submarine rocket (ASROC) systems, and also from most ASW aircraft, although they are slightly different lengths and weights. The P-8 Poseidon uses the High-Altitude Anti-Submarine Warfare Weapons Capability (HAAWC) GPS-guided parachute kit to drop torpedoes from high altitude.

https://www.militaryaerospace.com/sensors/article/14281632/antisubmarine-warfare-asw-airborne-torpedo

https://en.wikipedia.org/wiki/Mark_54_Lightweight_Torpedo