 The Mailplane was converted in 1933 to a high-speed test bed for the Armstrong Siddeley Tiger engine, the revised aircraft being known as the Avro 654.On return from Canada, the Mailplane was entered in the 1932 King's Cup Race, where it recorded the fastest speed of 176 mph (283 km/h), although owing to the handicap system, it came 29th.After conversion to the Avro 654, the aircraft operational life was short, it being dismantled at Woodford Aerodrome in 1934.