The Arpin A-1 was a two-seat low-wing monoplane which was powered by a single radial engine in pusher configuration, mounted behind the cabin between twin booms that carried the tail.
The booms were at wing height but the side by side two seat enclosed cabin sat on the wing with the uncowled 68 hp (51 kW) British Salmson AD.9R radial immediately behind, with its centre line well above the booms and tailplane.
In 1939 the A-1 was re-engined with an inverted inline 90 hp (67 kW) Blackburn Cirrus Minor I, which raised the maximum speed to 115 mph (185 km/h).
[4][5] With this engine it was known as the Arpin A-1 Mk.2 Only one A-1 was built at the company works at Longford, London, with the civil registration G-AFGB,[4][6] it first flew from Hanworth Aerodrome on 7 May 1938.
In December 1939 the A-1 was delivered to the School of Army Co-operation at Old Sarum too see if it would be suitable as an observation aircraft, it was not ordered into production and by 1946 the A-1 was scrapped.