Elsie Mackay (21 August 1893 – 13 March 1928) was a British actress, jockey, interior decorator and pioneering aviator who died attempting to cross the Atlantic Ocean with Walter G. R. Hinchliffe[1] in a single engined Stinson Detroiter.

It was a monoplane with gold tipped wings and a black fuselage, powered by a nine-cylinder, 300 horsepower (220 kW) Wright Whirlwind J-6-9 (R-975) engine, with a cruising speed of 84 miles per hour (135 km/h).

[12] In early March 1928, the Daily Express discovered that Captain Hinchliffe and Mackay were preparing for a transatlantic attempt by carrying out test flights at RAF Cranwell and were staying at the George Hotel in Leadenham[13] near Grantham.

The story was silenced by Mackay's threatened legal action as she intended to depart in secret while her father was in Egypt, having promised her family she would not make the attempt.

[2] At 8:35 am on 13 March 1928, Endeavour took off from RAF Cranwell, Lincolnshire,[14] with minimal fuss as Hinchliffe had told only two friends he was going and Elsie registered under the pseudonym of 'Gordon Sinclair'.

'[15] Approximately five hours later, at 1.30 pm the chief lighthouse keeper at Mizen Head on the south west coast of Cork, Ireland saw the monoplane over the village of Crookhaven.