During World War II, the US War Production Board ordered the cessation of all US piano manufacturing so that the factories could be used for the US war effort. Baldwin factories were used to manufacture plywood airplane components for various aircraft such as the Aeronca PT-23 trainer and the stillborn Curtiss-Wright C-76 Caravan cargo aircraft. While the employment of wood components in military aircraft could by no means be considered a resounding success, lessons learned in constructing plywood aircraft wings ultimately assisted in Baldwin's development of its 21-ply maple pinblock design used in its postwar piano models.