Ryan M-2 Monoplane Structural Wing Rib and Spar Blueprint (Circa 1926)

Original blueprint drawing detailing the structural wing rib construction, spar dimensions, and internal drag bracing of the Ryan M-2. — Ryan M-2 Monoplane Structural Wing Rib and Spar Blueprint (Circa 1926) · Donald A. Hall Estate Collection

An original factory blueprint from the Donald A. Hall Estate collection documenting the wing structure of the Ryan M-2 monoplane. The drawing details the internal wooden truss rib contours, capstrip dimensions, front and rear solid spruce box spars, and internal diagonal steel drag-wire bracing. Preserved by Hall as Chief Engineer of Ryan Airlines, this master drawing served as the structural baseline that Hall re-engineered and expanded to carry the massive fuel loads of the Ryan NYP Spirit of St. Louis.