The Lippisch P.12, P.13a and P.13b were related design projects for a ramjet-powered delta wing interceptor aircraft studied in 1944 by German designer Alexander Lippisch. The P.12 and P.13a were unarmed, relying on reinforced wings to ram its opponent. The P.13a and b were to be powered by powdered coal. The DM-1 was a full-size glider, flown to test the P.12/13a low-speed aerodynamics.The design series were unrelated to the earlier P.13 produced by Messerschmitt's Lippisch design office.