BAE Systems has started expansion of a manufacturing facility in Britain for increased production of components for F-35 Lightning II fighters.

The company said the 48,437-foot expansion to the factory at Samlesbury, Lancashire, follows the government's commitment to purchase 138 short take-off and vertical landing aircraft F-35 variants for the Royal Navy and Air Force.

"The further extension to the site signals another important milestone in the F-35 program and demonstrates BAE Systems' readiness meet the challenge of increased production rates," said Cliff Robson, BAE System's senior vice president for the F-35 Lightning II program. "We are proud of our role in the F-35 program, which will provide economic value to the region for decades to come. "

The factory produces F-35 aircraft tail assemblies for the Lockheed Martin fighter program. It also includes test facilities and sub-component assembly lines for the plane. The expansion, expected to be completed in 2017, will enable the manufacture of 160 tail units a year.

"There is a potential requirement for more than 3,000 aircraft over the next 20 years, meaning the F-35 Lightning II will continue to make a significant contribution to the UK economy through the work created in the 500 UK-based companies involved in the program."