Dan-Air
Hannah222, worthy of some research are both Dan-Air and British Air Ferries. Dan-Air as they were one of the first UK airlines to employ female pilots with 5(out of 550) in 1978. They also had the first female jet airliner captain calleds Yvonne Sintes who flew BAC111 and Comets until her retirement in 1980.
British Air Ferries had the first all female crew which was captained by Caroline Frost in 1977.
My Dad was a flight engineer on Halifaxes in WW2 and one of his favourite stories was about a delivery of a brand new Halifax III which was crewed by a diminuative blonde lady ATA pilot and a one armed male flight engineer. As a previous poster commented, a lot of the people who saw her climbing out of the aircraft asked where the pilot was!