In addition to performing test flights, Dornier often demonstrated the Do 31 prototypes to officials and the general public, such as at the 1969 Paris Air Show.

Seeking to counter this threat, the service actively researched the possibility of dispersed operations; one of the options was the use of the nation's Autobahns, which necessitated such aircraft to possess short take-off and vertical landing (STOVL) capabilities.

[2] As early as 1959, West German aircraft manufacturer Dornier had been informally working on several VTOL-related concepts,[3] although it would not be until 1961 that the design team would formalise what would become the Do 31.

Dornier's design team, based at the company's facility in Friedrichshafen, was headed by the aeronautical engineer Gustav Wieland.

Dornier had opted to incorporate the British-built Bristol Pegasus[note 1] vectored-thrust turbofan engine, an existing powerplant that was most famously used to power the Harrier jump jet.

[4][12] By mounting the engines in pods, the fuselage could accommodate a capacious hold for storing cargo, which was primarily accessed via a rear-facing loading ramp.

[4] According to aviation author Andrew Dow, while some initial teething issues were encountered, confidence in the aircraft grew quickly.

The ferry flight to reach the event established multiple Fédération Aéronautique Internationale (FAI) world records for the type.

[20][21][22][23][24] Public recognition was viewed as particularly valuable in light of Dornier's long-term ambitions for the Do 31, as the company foresaw civilian uses for the aircraft as a commercial VTOL transport.

During April 1970, it was announced that the project had been terminated, although the Do 31 performed its final public flight on 4 May 1970 during the Internationale Luft- und Raumfahrtausstellung (ILA) in Hannover.

[27] One of the alleged contributing factors towards the Do 31's cancellation was the relatively large drag and weight imposed by the lift engine pods, which reduced both the useful payload and range of the type compared to conventional transport aircraft.

A further development of the Do 31, referred to as the Do 131, intended to be powered by either twelve or fourteen liftjets, was also explored by Dornier; however, no prototype of this variant was ever constructed.