PATUXENT RIVER NAS, Md., 20 Nov. 2010. Lockheed Martin Aeronautics Co. in Fort Worth, Texas, will build 31 F-35 Lightning II joint strike fighter (JSF) combat jets under terms of a $3.5 billion contract modification from the U.S. Navy, announced late Friday. Lockheed Martin will build 10 conventional take-off and landing JSF for the U.S. Air Force; 16 short take-off vertical landing (STOVL) aircraft for the U.S. Marine Corps; one STOVL aircraft for the United Kingdom Royal Navy; and four carrier variant aircraft for the U.S. Navy.

The contract modification, which converts Lockheed Martin's F-35 contract type from a cost-plus-incentive-fee to a fixed-price-incentive (firm target), also will pay for ancillary mission equipment, flight test instrumentation, and manufacturing support equipment.

The contract modification combines purchases for the Air Force ($1.1 billion -- 31.6 percent); the Marine Corps ($1.7 billion -- 48.4 percent); the Navy ($582.1 million -- 16.6 percent); and the Royal Navy ($117.6 million -- 3.4 percent). Lockheed Martin will build the 31 joint strike fighter aircraft in Fort Worth, Texas, and should be finished by March 2013.

The F-35 program has about 900 suppliers in 45 states, and directly and indirectly employs more than 127,000 people, Lockheed Martin officials say. F-35 partner countries, which have invested more than $4 billion in the project, are the United Kingdom, Italy, the Netherlands, Turkey, Canada, Australia, Denmark, and Norway.

The F-35 is a supersonic, multi-role, 5th generation stealth fighter. Three F-35 variants are in production, each derived from a common design, developed together and using the same sustainment infrastructure worldwide. Lockheed Martin is developing the F-35 with its principal industrial partners, Northrop Grumman and BAE Systems.

Awarding the contract modification were officials of the U.S. Naval Air Systems Command at Patuxent River Naval Air Station, Md. For more information contact Lockheed Martin Aeronautics online at www.lockheedmartin.com/aeronautics, or Naval Air Systems Command at www.navair.navy.mil.