Production. Airplane manufacture, general. Kirksite is poured into a mold at the Inglewood, California, foundry of North American Aviation, Incorporated. The die that will be cast in this mold will be used in the forming of sheet metal parts for United Nations war planes. This plant produces the battle-tested B-25 ("Billy Mitchell") bomber, used in General Doolittle's raid on Tokyo and the P-51 ("Mustang") fighter plane, which was first brought into prominence by the British raid on Dieppe