Every Thursday, Cobham goes to war. Pilots clamber into its fleet of converted business jets and take on the RAF and Royal Navy in mock dogfights and electronic jamming raids.

The exercise is part of a long-standing contract run by the FTSE 250 company to test the military’s resilience. Cobham is one of the handful of defence suppliers capable of such demanding work.

Founded by Sir Alan Cobham in 1934, it has also developed technology used to refuel almost every western fast jet. That technology could soon be in private equity hands after a £4bn takeover by the American buyout firm Advent International.

The deal, supported by Cobham’s board, illustrates the vulnerability of the UK’s industrial base. It is a sobering reminder of the realities