He first submitted a monoplane design to the War Office when he joined the Army Balloon Factory at Farnborough in 1906, but they told him to build a biplane instead.

It wasn't until Dunne left the Balloon Factory and started his own company, the Blair Atholl Aeroplane Syndicate Ltd., that a monoplane could be built.

Since sweepback placed the tips well behind the centre of gravity, they provided longitudinal (pitch) stability in just the same way as a conventional tailplane, mounted at lower incidence than the wing.

A substantial undercarriage structure was mounted at the bottom of the frames, comprising a long pair of skids which extended from the pusher propeller line well forward beyond the nacelle and curving strongly upwards.

[2][5] The modified aircraft first appeared, not quite ready for flight and with a dummy engine, at the Olympia Aero Show in March 1911 where it was described as the "Dunne Auto Safety Aeroplane".

In January 1912 Dunne demonstrated the D.7 to members of the Royal Aeronautical Society, writing a note whilst flying hands off at 60 mph.

A joint venture between the syndicate and the French company Astra, it was built in France and successfully flown at Villacoublay by both Dunne and N.S.