At the beginning of the war Blacker drove vehicles for the Blood Transfusion Service, but in 1942 she was called up for service and joined the WAAF. Taken on as an Aircraftwoman Motor Transport Driver she received a training course to upgrade her driving skills and then served in Fighter Command at Biggin Hill. From the beginning she seems not to have let her new life get in the way of her art and she quickly latched on to the opportunities that such a large pool of new faces presented to her.
Military life is punctuated, more than most occupations perhaps, with long stretches of relative calm when being 'on duty' consists of being where you are supposed to be, but sometimes with little to do, interspersed with periods of frantic activity.
Blacker's ability with pencil and brush must have made her a popular person to have around, for not only could she keep herself active, but she could offer her sitters that special pleasure of participating in the production of a portrait whilst sitting quite still and doing nothing except perhaps chatting.
Her skill, and the pleasure others derived from it, evidently gave her access, not just to her immediate colleagues, but to the sick quarters, crew-rooms and miscellaneous offices all over her stations. As a result she produced a record of life on an RAF station which it would be hard to equal.