Final answer:
The next generation lightweight, variable speed, antisubmarine torpedo that combines the MK 50 search and homing system with the propulsion system of the MK 46 torpedo for optimized performance in shallow water is called the MK 54 Lightweight Torpedo.
Step-by-step explanation:
The next generation lightweight, variable speed, antisubmarine torpedo that combines the MK 50 search and homing system with the propulsion system of the MK 46 torpedo for optimized performance in shallow water is called the MK 54 Lightweight Torpedo. The MK 54 is designed to be launched from surface ships, helicopters, and fixed-wing aircraft, making it versatile for various mission scenarios. It has advanced capabilities such as advanced guidance and control systems, improved target detection, and a reprogrammable, advanced digital signal processor for better performance in complex environments.