Production. Airplane manufacture, general. After steel templates have been fastened to large sheets of metal, a router cuts a dozen sheets under each template in a matter of minutes. The work is being done in the Inglewood, California, plant of North American Aviation, Incorporated. This plant produces the battle-tested ("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