Lockheed Martin Corp., Mission Systems and Sensors, Owego, N.Y., was awarded a $23,864,671 firm-fixed-price contract.  The award will provide for the procurement of four modernized radar frequency interferometer for Apache AH-64 helicopter.  Work will be performed in Owego, N.Y., with an estimated completion date of Dec. 31, 2013.  One bid was solicited, with one bid received.  The U.S. Army Contracting Command, Redstone Arsenal, Ala., is the contracting activity (W58RGZ-12-C-0035).