A.21/2, first and only production example, completed July 1931.

After a series of tests with the first production examples, it became apparent that the design was seriously flawed.

The prototype was built of wood, although production examples would have a metal structure.

The base model, the first production example completed in July 1943.

Only 24 production examples of the type were built before the contract was cancelled.

Production began in late 1938, and the first production example flew on 29 January 1939.

All production examples were constructed during the first few weeks of 1969.

It also featured the first production example of hub-center steering on a motorcycle.

A total of 100 aircraft were ordered, with the first production example flying on 4 July 1947.

This was followed by a further 58 production examples delivered between 1948 and 1952.