William A. Baker had undertaken the construction of the six seat Henderson HSF 1 (G ABVF) and all three of the Henderson Glenny Gadfly monoplanes which were also designed by K. N. Pearson, M.C., AFRAeS.
Glenny & Henderson company at Byfleet, Surrey, UK, built a Mk.I standard aircraft G-AAEY c/n 1. It was first flown in April 1929, at Brooklands. It was converted to Gadfly Mk.II statue later that year. It was scrapped in June 1934.
The second built was c/n 2 G-AARJ, built ads a Mk.II. This was as the Mk.I but fitted with Pearson rotary ailerons. It first flew in August 1929, from Brooklands. In 1930 it was sold in Canada as CF-AMG but was written off on 25 August 1931.
One aircraft was built as a Mk.III, like the Mk.II but fitted with a Salmson AD.9 radial engine. G-AARK was first flown in late 1929, at Brooklands. It was withdrawn from use in 1930 and put into storage at Brooklands until scrapped there in 1933.
Mk.I
G-AAEY c/n 1
Engine: A.B.C. Scorpion
Span: 25.10 ft
Length: 17.10 ft
Mk.II
G-AARJ c/n 2
Engine: A.B.C. Scorpion
Span: 25.10 ft
Length: 17.10 ft
Mk.III
G-AARK
Engine: Salmson AD.9
All Aero 