What is shown by a destroyer as the Navy proceeds toward the next level of technology? The answer is currently coming to fruition with USS Patrick Gallagher the last of the Flight II(A) Technology Insertion Arleigh Burke-class destroyers before giving way to the next iteration. The upcoming builder’s trials are more than just another standard event before delivery. Instead, they signify a transfer between two generations of the Navy’s most trusted surface combatants. Whereas one generation was defined by continuity and reliability, the other has come to emphasize much higher demands for radar power, cooling, and electrical headroom.
Patrick Gallagher’s builder’s trials will be conducted based on well-known Burke-class features: displacement of nearly 9,200 tons, 96 Vertical Launch System (VLS) cells, the main battery of a 5-inch gun, torpedoes, close-in defensive weapons systems, and two MH-60R helicopters. And here is the catch. In spite of some upgrades compared to earlier variants, the vessel will rely on a hull form and basic configuration the Navy used and tested in its previous decades.
It should be clear that those features can only become reality during the sea trials. At that stage, the ship will be subjected to propulsion and maneuvering tests, endurance trials, and emergency stopping runs, while the auxiliary systems will be operated in conjunction with one another. At that point, mechanical systems, electricity, and ship controls are no longer checked separately. What really becomes clear during sea trials is whether the vessel meets acceptance standards while out at sea.
Underneath that complex machinery is a tried-and-true propulsion architecture with four LM2500 gas turbines generating approximately 100,000 shaft horsepower. Not surprisingly, that engine has become common throughout the fleet. As of early 2025, there were 74 active Arleigh Burke-class destroyers fitted with those engines. There is a reason for why the class remained operationally viable for such a long period of time. No matter how much a ship may have evolved technologically, it can still rely on its propulsion system when going on deployments, escorting convoys, or providing air-defense capability.
However, the truth is that what the Flight II(A) cannot accomplish is just as significant as what it can do. The upcoming generation of Arleigh Burke-class destroyers will revolve around the AN/SPY-6 radar, which is far more sophisticated compared to its predecessors (AN/SPY-1). According to CSIS background on SPY-6 radar, the system is expected to deliver thirty times better sensitivity and ability to handle many more simultaneous tracks. This change is not a mere improvement for sensors. Instead, it means the need to make significant alterations to ship power generation, thermal capabilities, and overall internal capacity.
This factor makes Patrick Gallagher’s trials quite valuable indeed. The ship will bring to completion the latest variant of the Arleigh Burke-class destroyer, which has been characterized by predictable performance, established logistics lines, and a well-understood combat system. At the same time, the trials will demonstrate the challenges of the next evolution of the design. Finally, the ship has earned its name, honoring Marine Corps Cpl. Patrick Gallagher, who was awarded the Navy Cross for defending his fellow service members in Vietnam. Engineers will have plenty of questions about shaft horsepower, stability, and overall systems integration. For the rest of the fleet, the significance of the trials is much simpler the Burke formula continues to work for another decade.