The P-8 Poseidon, a multi-mission maritime patrol and reconnaissance aircraft, has been called the "perfect submarine hunter".

Developed for the US Navy by Boeing, the Poseidon is a militarized variant of Boeing's 737-800 passenger aircraft.

In service since 2013, the aircraft has two variants -- the P-8I, flown by the Indian Navy, and the P-8A, flown by the US Navy and navies of the United Kingdom, Australia, Norway and New Zealand.

The German and South Korean navies also selected the P-8.

Boeing has called the Poseidon a "proven" system, with more than 155 aircraft in service and 500,000 mishap-free flight hours across the globe.

The Poseidon is capable not only of finding and tracking enemy submarines but of attacking and destroying them.

The aircraft can be equipped with torpedoes and Harpoon anti-ship missiles, according to the National Interest, along with 129 air-parachuted sonobuoys, devices used to detect objects moving in the water.

"Packed in canisters, the 129 sonobuoys are the most important gear onboard and allow the P-8 Poseidon to survey a larger area in search of submarines," reports the Barents Observer.

"A sonobuoy ejected from the plane in an area of a suspected submarine will go down to a pre-programmed depth, somewhere between the surface and a few hundred meters deep in the water."

Multi-mission aircraft

The P-8 Poseidon is capable of conducting sonobuoy sub-hunting missions from higher altitudes than can surface ships or lower-flying aircraft, decreasing its vulnerability to enemy surface fire and swarming small boat attacks.

Capable of flying up to 41,000 feet (12km) high, the Poseidon is also designed to operate at extremely low altitudes over the ocean, expanding its capacity to search for potentially hostile submarines.

Poseidon's altitude range and speed of up to 490 knots (907km/hour) allow for the aircraft to respond to a wide variety of missions, including humanitarian search-and-rescue operations.

"The Boeing P-8 is truly a multi-mission maritime patrol aircraft, excelling at anti-submarine warfare; anti-surface warfare; intelligence, surveillance and reconnaissance and search-and-rescue," according to Boeing.

The Poseidon is capable of operating on 10-hour missions at ranges up to 1,200 nautical miles (2,222km), with four hours on station.

The Poseidon's ability to detect submarines is supported by its active multi-static and passive acoustic sensor system and by an electronic support measure system.

Its AN/APY-10 radar, which sits in the aircraft's nose and has a reported range of 250km, has modes that include color weather, synthetic aperture radar (SAR), inverse SAR, periscope detection and navigation.

It also has electro/optical infrared cameras optimized to scan the ocean's surface, and a magnetic anomaly detector capable of pinpointing the location where a submarine went under the surface.

The aircraft's surveillance systems are capable of being integrated with other military assets to enhance mission effectiveness.

"The surveillance aircraft can also operate as a 'node' within a broader sub-hunting network consisting of surface ships, unmanned surface vessels, aerial drone-mounted maritime sensors and submarines," according to the National Interest.