The Coventry Ordnance Works (COW) 37 mm automatic gun was used, which had been developed for this purpose some years earlier.

The design was an open cockpit single engined metal monoplane with fabric covering.

The aircraft design had already been submitted for specification F.20/27 as the Westland Interceptor but had lost out to the Gloster Gauntlet.

This concept was similar to the Schräge Musik system used by Germany during World War II.

The plane first flew at the end of 1930 but the trials did not give satisfactory results to continue with the idea.