L3Harris Successfully Tests Power Plant for U.S. Navy’s Next-Gen MK 54 Torpedo

L3Harris Technologies has completed a major step in developing the U.S. Navy’s future underwater weapons by successfully testing the power plant system for the MK 54 MOD 2 Increment 2 Advanced Lightweight Torpedo. This test marks a key milestone in the Navy’s efforts to upgrade its undersea warfare tools with smarter and more powerful systems.

At the heart of this breakthrough is the Stored Chemical Energy Propulsion System (SCEPS) — a cutting-edge propulsion technology that uses chemical energy to generate steam and drive a turbine, allowing the torpedo to travel faster and farther under water. The recently tested power plant is the core of this propulsion system.

According to Scott Alexander, President of Missile Solutions at Aerojet Rocketdyne, a division of L3Harris, this successful trial confirms the strength and reliability of the power plant design. It also clears the way for the next round of testing, where the entire propulsion system — including the tail and afterbody — will undergo design verification later this year.

The MK 54 MOD 2 torpedo is an upgraded version of the Navy’s widely used MK 54 lightweight torpedo. It’s designed for both deep and shallow water missions and is typically launched from ships, helicopters, and P-8A Poseidon maritime patrol aircraft. With SCEPS, the new version is expected to deliver greater range, speed, and stealth, making it more effective against modern underwater threats.

One of the key technologies behind SCEPS is a lithium boiler, which produces intense heat to create high-pressure steam. This steam spins a turbine, which in turn drives the torpedo forward. Compared to older propulsion systems, this method is compact, powerful, and quiet — a major advantage in underwater combat.

L3Harris is developing and manufacturing SCEPS components at its Center of Excellence for Undersea Propulsion Manufacturing in Orlando, Florida. This facility is not only producing parts for current Navy contracts but also working on new prototypes to push the technology even further.

With the U.S. Navy focusing more on undersea dominance, especially in regions like the Indo-Pacific, the SCEPS-powered MK 54 MOD 2 could become a vital asset in future naval operations. The current progress places L3Harris at the center of this strategic transformation, giving the Navy a more capable and modern edge beneath the surface.

The design verification testing scheduled later this year will be critical to finalize the system for deployment. If all goes well, the U.S. Navy could begin fielding the new torpedo variant in the near future, signaling a new era in underwater weapons technology.