On 18 December 1939, Vickers Wellington bombers carried out a raid on German shipping in what became known as the Air Battle of the Heligoland Bight. Detected on radar and engaged en route to their targets, over half the attacking force was destroyed or damaged beyond repair. Ludlow-Hewitt presented a report on the attack on 22 December 1939, noting that flying straight and level for the CSBS made the bombers easy targets for fighters and anti-aircraft gunners. He again pressed for a new bombsight that featured stabilization to allow the aircraft to manoeuvre while it approached the target.