The Halton Mayfly was a British two-seat biplane designed by C.H. Latimer-Needham and built by the Halton Aero Club between 1926 and 1927.[1]RegisteredG-EBOO and named the HAC.1 Mayfly it first flew on 31 January 1927.[1] It was converted to a single-seater and was flown in a number of air races including the King's Cup Race.[1] It was entered in the 1926 Lympne light aircraft trials as No. 8 but failed to arrive in time for the elimination trials.[2]
By 1928 the aircraft had been converted from a biplane to a parasol monoplane and was renamed the Halton HAC.2 Minus.[1] It was used again for air racing, being entered in the 1928 and 1928 King's Cup Races.[1] The aircraft was dismantled at Halton in 1930.[1]