WASHINGTON - Two of seven upgraded P-3C maritime surveillance aircraft were delivered to Pakistan recently under the US Governments Foreign Military Sales programme, a news release said Thursday. Lockheed Martin, an American security firm headquartered in Bethesda, Maryland, said the most recent aircraft delivery occurred on Jan 7 to the Naval Air Station in Jacksonville, Florida, for subsequent transfer to Pakistan. Lockheed Martin delivered the first plane in October 2009. Lockheed Martin is upgrading the P-3Cs aircraft and mission systems and providing maintenance under a 2006 contract from the US Navys Naval Air Systems Command, the news release said. The aircraft support anti-ship and anti-submarine warfare missions and will enhance Pakistans ability to conduct maritime surveillance in littoral and deep-water environments. The aircraft are designed to have a single integrated tactical picture of the battle space, drawing upon data from aircraft sensors and information from other platforms. These aircraft incorporate a variety of enhanced features including communications, electro-optic and infrared systems, data management, controls and displays, mission computers and acoustic processing, said Mike Fralen, director for Lockheed Martin Mission Systems and Sensors maritime surveillance programmes. The P-3 is the primary maritime patrol and reconnaissance aircraft operated by the US Navy and 16 allied countries. Its roles include anti-submarine warfare, anti-surface warfare, surveillance and reconnaissance, search and rescue, drug interdiction, economic zone patrol, airborne early warning and electronic warfare.