Sikorsky Aircraft Corp., Stratford, Conn., was awarded a $16,321,909 firm-fixed-price contract.  The award will provide for the modification of an existing contract to procure transmissions for the Black Hawk helicopter.  Work will be performed in Stratford, with an estimated completion date of April 30, 2015.  The bid was solicited through the Internet, with one bid received.  The U.S. Army Contracting Command, Redstone Arsenal, Ala., is the contracting activity (W58RGZ-09-D-0067).