These were Auster AOP.6, T.7 and T.10 aircraft which were updated and modified with de Havilland Gipsy Major 10-1-1 engines.

Initially two versions were offered for sale in the civilian market from 1960: In 1962 the Beagle A.61 Terrier 2 was introduced with a greater span tailplane, wheel spats and a metal propeller.

It was also out-dated as, by 1961, most competing manufacturers were introducing new designs which were all-metal, with tricycle undercarriages and powered by more modern engines such as Lycoming or Continental (e.g. the Cessna 150 and the Piper Cherokee).

However the Terrier has found many adherents among vintage light aircraft owner pilots.

Examples of the type were purchased by owners in the United Kingdom, Eire, Germany, Netherlands, New Zealand and Sweden.