Developed from the M.3B Falcon Six, the M.7 Nighthawk, of which five civil examples were built, was intended for use as a trainer and three-seat communications aircraft, and was eventually ordered by the RAF as the M.16 Mentor.
Both peace and war demand that air pilots shall be able to find their way safely and surely over long distances by night, and that they must be capable of flying straight and level when all land and sky marks are blotted out by fog or heavy weather. In the early days of aviation this type of flying was either carefully avoided and left to the birds, or undertaken only by the toughest of aviators.
However, with the coming of long-distance air lines a new technique was initiated, known as blind - or instrument - flying, and this was later brought nearer perfection by military necessity.
Intensive blind-flying instruction became an increasing feature of R.A.F. training as the outbreak of war began to gather and, in 1936 the Miles organisation produced the aptly-named Nighthawk, basically a development of the famous Falcon Six, but with dual controls and instruments and side-by-side seating. A black canvas hood was arranged to fit over the left-hand seat, which was occupied by the pupil, this limiting his vision to the instrument panel only.

Developed from the M.7 Nighthawk, the Miles M.16 Mentor was designed to meet the requirements of
Air Ministry Specification 38/37 for a three-seat cabin monoplane for use in a communications role; it was required to be suitable also for instrument or radio training by day or night. The prototype (L4932) was flown on 5th January 1938, service testing resulting in an order for 45 aircraft including prototypes, This 35 ft 7 in span aircraft was powered by a 200 hp de Havilland Gipsy Six I inline engine, providing a maximum speed of 156 mph at sea level. Used by the RAF for communications and training, only one of them surviving the war.