As the Swordfish torpedo-bombers headed back to the carrier HMS Ark Royal on the afternoon of 26 May 1941 they came across some other warships, which might well be the enemy.

The attention of formation leader, Lieutenant Commander James Stewart-Moore, was drawn to one of his own aircraft, which was equipped with air search radar. Via semaphore flags, a young officer in its crew indicated to his leader that a contact had been picked up, around ten miles away.

Destroyers came into view below, whi...