During 1942, while still working on the Messerschmitt Me 163 rocket fighter, Alexander Lippisch developed a sharply-swept, leaf-shaped delta wing which he believed was capable of supersonic flight.

A model of it showed a typical configuration comprising a highly-swept delta flying wing with a protruding nose intake, raised cockpit canopy and single tail fin.

The wing centre section was hollow, with air ducts on either side of the cockpit leading to a large cavity which comprised the ramjet.

It underwent much the same variations of form as the P.12, being presented in a brochure with the large fin and integral raised cockpit, and with an articulated, double-hinged landing skid.

Initially, it was proposed to employ a wire-mesh basket holding even-sized granules of brown coal, placed in the lower region of the internal airflow.

[1] Other fuels considered promising, due to their ability to generate flammable vapours, included bituminous coal, or pine wood heat-soaked in oil or paraffin.

Lippisch however took little interest; having moved on from the design, he set up the glider project only to keep students of Darmstadt and Munich Universities from being drafted into a by-then hopeless war.

Before the DM.10 was begun, in December 1944 Lippisch's attention moved to a revised design similar in some respects to the earlier P.11 / Delta VI but keeping the P.13a's sharp sweep angle and solid-fuel ramjet with rotating burner.

The wing was essentially that of the P.12/13 but larger at 6.9 metres (22 ft 8 in) span and cut short at the front for unswept air intakes at the roots.

Like the P.11 it had a conventional nose nacelle and cockpit with small twin tail fins either side of a centre section inset on the straight wing trailing edge.