General Atomics Aeronautical Systems (GA-ASI) and the US Navy have expanded the anti-submarine warfare (ASW) capacity of the MQ-9B SeaGuardian remotely piloted aircraft.
The aerospace company and the USN validated the type’s increased capacity on 17 December 2025, according to GA-ASI.
The company did not list the location of the test, nor did it specify the exact number of sonobuoys deployed. The USN has tried out SeaGuardian’s ASW capacity in several recent exercises, and GA-ASI says that it is expected it to deploy it operationally this month.
The SeaGuardian can carry a single sonobuoy dispenser system (SDS) on each of its four wing hardpoints. Each SDS can hold 10 A-size or 20 G-size sonobuoys, giving total potential capacity of 80.
By comparison, the USN’s Boeing P-8A anti-submarine warfare aircraft can deploy around 129 A-size sonobuoys, or over 250 G-size sonobuoys. The USN’s key ASW helicopter, the Sikorsky MH-60R, can deploy just 25 A-size or 50 G-size sonobuoys.
GA-ASI specifies three sonobuoy types that were involved in the test: the AN/SSQ-36, which checks the water’s acoustic qualities, the AN/SSQ-53G, which listens for the noise generated by submarines and other vessels, and the AN/SSQ-62F, which emits active “pings” to identify a target’s exact location.
Curiously, GA-ASI claims that this was the first time Multi-static Active Coherent (MAC) buoys were dropped from an uncrewed aircraft. MAC makes ASW more efficient by creating a network of sonobuoys: if sound bounces away from the source of the ping, a receiver can pick it up elsewhere.
The USN’s MAC capable buoys are understood to include the AN/SSQ-125, which transmits an active ping, and the AN/SSQ-101, which listens for pings bouncing off submarines.
“Expanding sonobuoy capacity, including Multi-static Active Coherent technology for SeaGuardian, has been an integral part of our advanced ASW strategy to broaden and enhance search areas,” said GA-ASI president David R. Alexander.
“The wider maritime coverage our MQ-9B’s ASW capability provides is extremely valuable to our customers.”
For several years, GA-ASI has touted the potential of the MQ-9B in the ASW role. This includes tests in March 2024 off the coast of southern California.
According to the US Department of War’s recent report about China’s military buildup, Beijing continues to add to its submarine force. ASW capability will be at a premium should a conflict with China break out in the western Pacific.
