Dornier Do 31

The Dornier Do 31 is an experimental jet-propelled vertical take-off and landing cargo aircraft designed and produced by the West German manufacturer Dornier. It grew from German Air Force interest in short take-off and vertical landing aircraft and from NATO specification NBMR-4 for a VTOL tactical support aircraft. Three were built, two able to fly and one static airframe, and used for testing. The first prototype made its maiden flight on 10 February 1967, powered by its two Pegasus engines alone, and the first hovering flight followed in July 1967. Dornier demonstrated it at events such as the 1969 Paris Air Show and the type set several world records, but high cost and technical and logistical difficulties led the German Air Force to end its VTOL trials, and the Do 31 lingered as a research project before its manufacturer abandoned all activity.