The company's UK production facility has delivered the 500th aft fuselage for the F-35 aircraft, and the milestone coincided with the visit of the US ambassador to the UK.
"Lancashire has a very proud history manufacturing planes for the British military and it is fantastic to see that tradition continuing strong to this day," ambassador Robert "Woody" Johnson said.
"The highly skilled workers at the BAE Systems facility in Samlesbury are now helping to produce the most sophisticated fighter jet the world has ever seen: the F-35.
"Combining incredible stealth with supersonic speed, the F-35 is a game changer which will play a vital role in America and Britain's collective defence for decades to come.
"The program is led by prime contractor, US firm Lockheed Martin, with BAE Systems and Northrop Grumman making up its principal industry partners."
Johnson was joined on the tour by Charles Woodburn, BAE Systems chief executive; Chris Boardman, group managing director for air; and Tom Fillingham, senior vice president of the US programs business, which leads BAE Systems air sector’s role in the F-35 program.
“Delivering the 500th aft fuselage of the aircraft is a major milestone for us, and we know by continuing to deliver we will maintain our place on the program and our strong relationship with the US."