The Avro 627 Mailplane was developed in 1931 by Avro from the Avro Antelope bomber as a mail plane for use in Canada. Only one was built which, following trials in Canada, was returned to England. The Mailplane was converted in 1933 into a high-speed test bed for the Armstrong Siddeley Tiger engine, the revised aircraft being known as the Avro 654. Dismantled at Woodford in 1934.