Military avionics experts at the Boeing Co. in Seattle are making several improvements to the P-8A Poseidon maritime patrol aircraft avionics to upgrade the plane's ability to detect, track, and attack enemy submarines and surface ships. These improvements, part of a package of electronics enhancements expected to become operational in 2020, will upgrade the Poseidon aircraft's signals intelligence (SIGINT) capabilities, as well as its ability to network both among onboard subsystems and with other military systems. Officials of the U.S. Naval Air Systems Command (NAVAIR) at Patuxent River Naval Air Station, Md., announced a $71.6 million order to the Boeing Defense, Space & Security segment in Seattle to build, integrate, and test several Poseidon Increment 3 Block I capabilities. This order to Boeing is part of the third of three phases of planned improvements to the Poseidon aircraft, a ruggedized version of the Boeing 737 single-aisle jetliner hardened for long-range anti-submarine warfare; anti-surface warfare; and intelligence, surveillance, and reconnaissance missions.