Although the pace of aeronautical development caused its rapid replacement in frontline service, its useful life was extended into the Second World War with many being converted into target tugs and wireless trainers.

Compared with the earlier Wapiti, the Wallace was 20 inches (0.51 m) longer, incorporated an improved undercarriage and was powered by a 655 hp (488 kW) Bristol Pegasus IV engine.

Westland designed an improved version, the Mk II which was fitted with a more powerful engine and the then-novel idea of an enclosed canopy over both crew positions.

Both aircraft received modifications that included fitting heating and oxygen equipment, fully enclosing the rear cockpits and using highly supercharged Bristol Pegasus IS 3 engines.

[6] Data from The Hamlyn Concise Guide to British Aircraft of World War II[7]General characteristics Performance Armament