May Constance Assheton Harbord (6 June 1866 – 7 February 1928), was the first woman to obtain an Aeronaut's Certificate in the United Kingdom, in 1912.

May Harbord flew regularly, often with John and Eleanor Shelley-Rolls, another keen balloonist and sister of Charles Rolls.

'Nebula' in the winter of 1906/7 and flew it for the first time on 12th January 1907, with Mr and Miss Moore-Brabazon as passengers, making that flight the first in the UK by a woman of her own balloon.

[9] Assheton Harbord was awarded the "Mortimer Singer Plate" in 1909 for the longest balloon journey in July, August or September in 1908.

[11] Assheton Harbord was a member of the Ladies Automobile Club from about 1909[12] and also served in the Volunteer Motor Mobilisation Corps in 1915.