In early 1935, Appleby started construction of a Mignet HM.14 Flying Flea, in a shed at Heston aerodrome loaned to him by his employer, Airwork Ltd. Appleby made a main wing of 5 meters span, on the advice of Mignet, who was unaware that a heavier than normal engine (a water-cooled Ford 10 unit) was to be fitted.