It seems like you can't even hide from drones under the sea now, with General Atomics (GA) flight-testing its MQ-9B SeaGuardian maritime patrol unit. It was trying out the new Expanded Sonobuoy Dispensing System (ESDS) for hunting submarines where they hide.
One of the major functions of modern navies is submarine hunting. Small wonder when you consider that a nuclear ballistic missile submarine is the most powerful weapon system in history, so it's a good idea to keep an eye on them. Not to mention that submarine attacks on shipping almost brought Britain to its knees during the Second World War.
The importance of this is so great that the Royal Navy's main job during the Cold War was as the anti-submarine fleet of NATO. The outcome of that conflict was in large part due to the ability of NATO to track Soviet submarines and to keep their missile boats penned up in the Arctic Ocean.
Today, anti-submarine warfare is just as intense, with the major powers working at ways to expand and refine their capability to detect, track, and intercept hostile undersea craft. One arrow in this marine quiver is the use of aircraft to patrol over vast distances while dropping sonobuoys to seek out subs.
Sonobuoys are expendable instrument packages that look like long metal canisters. When dropped from a plane or helicopter, they open and stretch out to expose sensors and a drogue mechanism to slow their one-way path to Davy Jones.
They come in a variety of types, including ones that measure temperature, passively listen for submarines, actively broadcast sonar pings, and act as transceivers to set up temporary networks to cover vast areas of the ocean.
The bottleneck is being able to keep enough assets in the air on patrol at any one time in case they are needed. Helicopters don't have much endurance and crewed aircraft like the P-8A Poseidon, despite their long range, can only manage about four hours on station. Even with in-flight refueling, the crew can only handle so long in the air.
It's to fill this gap that GA and the US Navy are developing heavy drone variants for anti-submarine patrols. Demonstrations of the concept started in 2017 and the latest tests in December show the increasingly sophisticated nature of the systems.
The new ESDS pods used on the MQ-9B SeaGuardian allow such craft to deploy Multi-static Active Coherent (MAC) sonobuoys for the first time. In addition, the new pods effectively double the drone's payload capacity. This allows the SeaGuardian to carry out deep ocean patrols and take on much of the operational burden of Poseidon crews, allowing them to concentrate on more important missions.
"Expanding sonobuoy capacity, including Multi-static Active Coherent (MAC) 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."
Source: General Atomics
