Mahon attended a Sacred Heart convent in Dublin and went on to get a job with an accountancy firm until the war.
During her childhood in Dublin there had been a visit from Sir Alan Cobham's Flying Circus and Mahon had taken a ride and for a moment been given control of the airplane.
When the war began Mahon moved to Northern Ireland to drive ambulances with the Women's Auxiliary Air Force in Ulster.
Although Mahon predominately worked as a stay at home mother after the war, in 1973 she volunteered with the group that became the Royal International Air Tattoo at Fairford, Gloucestershire.
Hill took a job with the United Kingdom Atomic Energy Authority so Mahon moved around the UK with him from Cumbria to Caithness and Hampshire.