Lockheed-Martins P3C Orion is a four-engine turbo-prop, anti-submarine and maritime surveillance aircraft. As a patrol aircraft, it has advanced submarine detection sensors such as directional frequency and ranging sonobuoys and magnetic anomaly detection equipment. The planes can carry a mixed payload of weapons internally and on wing pylons. The aircraft is designed to have a single integrated tactical picture of the battle space, drawing upon data from aircraft sensors and information from other platforms. The United States handed two P3C Orion aircraft to Pakistan Navy in late April 2010. By 2012 Pakistan Navy is expected to take delivery of a total of eight P3C aircraft. Lockheed has upgraded the P-3Cs aircraft and mission systems and is providing maintenance under a 2006 contract from the US Navys Naval Air Systems Command. According to Mike Fralen, director for Lockheed Martin Mission Systems and Sensors maritime surveillance programmes, 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.