Beating Gravity - Dornier Do.31

The Dornier Do.31 was developed to West German requirements as a prototype VTOL transport able to support VTOL combat aircraft in the field. The fuselage was left free to accommodate troops or cargo by locating the power plants in wing nacelles.

The inner nacelles held two turbofans, and the outer nacelles were detachable pods holding four RB.162 direct-lift engines. These pods were to be optional when, later, thrust-deflecting main engines were fitted.

The Do.31E1 first prototype flew in February 1967 with two Pegasus engines. The Do.31E2 second prototype followed in July with all ten engines. From December 1967 full forward and backward transitions were made.

Dornier also proposed a Do.231 100-seat passenger or a similar freight version for production, with twelve 13,100 lb (5942 kg) thrust RB.202 lift engines and two 24,000 lb (10886 kg) thrust propulsion engines.