The Defender was the first fighter aircraft to serve with the Krakabloa Air Arm. The need for a fighter arose from the heavy losses being sustained by 'Conveyor' bomber aircraft which were flying unescorted to their targets on the Wright Isles and so the defender was designed to provide fighter cover after a failed earlier attempt to produce a fighter aircraft. There was a great amount of redesign and modification between the first mark of Defender and the last.

The Mk.2a was a fast plane for its time, able to outpace its rival, the 'Saviour', but not out-turn it. It has a large wingspan to enable a significant glide distance. Most operated initially from bandit airport, but a number of accidents required the type to be moved. Almost all Mk.2a Defender's have been scrapped, although 5 remain in storage in various states of disrepair with one airworthy example used for air displays.