By the middle of March, the Gotha squadron was once again ready to attack England but had to support the Spring Offensive which started on 21 March, being used to bomb Calais, Dunkirk, Boulogne and troop concentrations and railways. On 9 May, Rfa 501 suffered a catastrophic blow when four aircraft attempted to bomb Dover. High winds caused them to be recalled when over the Channel, by which time fog had covered their base. One aircraft landed safely, the crew of a second survived a crash in which the aircraft was damaged beyond repair and the remaining two crashed with the loss of all but one member of each crew.