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WASHINGTON, April 16 (Reuters) - The U.S. Defense Department has approved the first trans-Atlantic flight of Lockheed Martin Corp's F-35 fighter jet in July to take part in two international air shows near London, senior defense officials said Wednesday.
The new warplane will make its international debut at the Royal International Air Tattoo, or RIAT, an annual military air show help outside London in July, followed by appearances at the Farborough air show, held every other year, according to the officials, who were not authorized to speak publicly.
The jet's appearance at the air shows will be closely watched by potential buyers, including Canada and Denmark, which helped fund the plane's development but are rethinking their planned procurements.
F-35 backers say the decision reflects growing confidence in the $392 billion program, the Pentagon's costliest weapons program, but skeptics say the plane still faces challenges with completing the software needed to integrate weapons on the jet.
Britain, which contributed $2 billion to the development of the new radar-evading fighter jet and plans to buy 138 F-35s in coming years, asked for the jet's participation to help showcase the increasing maturity of the new radar-evading plane. Britain was also the first international partner on the program.
Current plans call for several F-35s to participate in the air shows, including at least one of the three F-35 B-model jets already built for Britain, with a UK pilot at the controls.
U.S. defense officials said the overseas flights would be used for additional training and would help the F-35 program office learn how the plane's logistics, maintenance, aerial refueling, and security systems work overseas.
Pratt & Whitney, a unit of United Technologies Corp, builds the single engine that powers the plane. Britain's Rolls Royce Group RR.L builds the lift fan that enables the B-model of the F-35 to land like a helicopter.
Other major contractors on the F-35 program include Northrop Grumman Corp and Britain's BAE Systems.
(Reporting by Andrea Shalal; Editing by Doina Chiacu)