She was born in Whanganui, New Zealand in 1912[1] and flew in the Second World War as a pilot in the British civilian Air Transport Auxiliary and died in service.

After flying in Charles Kingsford Smith's Southern Cross, she was one of the four female pilots (alongside Trevor Hunter, June Summerell and Eva Parkinson) to escort New Zealand aviator Jean Batten on 21 July 1934 in her arrival in New Zealand following her record flight from England to Australia.

[4][5] Winstone applied to be a pilot for the Air Transport Auxiliary while living in New Zealand and they informed her she would be considered if she was able to be examined in Britain.

[6] She died in service on 10 February 1944 when her Spitfire LF.1X MK616's Merlin engine failed and the aircraft crashed near Tong Castle, in Shropshire.

[1] She had been transporting the plane from the Vickers Aircraft factory at Cosford to the RAF 39 Maintenance Unit at Colerne, Wiltshire.