Original Master Pencil Drawing of Ryan NYP Wing Structural Layout (1927)

Original technical pencil drawing of the Ryan NYP wing assembly layout showing rib spacing, wing tanks, and aileron dimensions. — Original Master Pencil Drawing of Ryan NYP Wing Structural Layout (1927) · Donald A. Hall Estate Collection

A foundational master engineering artifact hand-drafted by Donald A. Hall Sr. in March 1927 at Ryan Airlines in San Diego. This detailed pencil drawing on technical drafting paper details the structural architecture of the Spirit of St. Louis's 46-foot wing, specifying a 23-foot semi-span (276 inches), rib stations, spruce box spar depths, internal drag-wire bracing, and the cutouts for three wing fuel tanks totaling 153 gallons. Annotated with precise dimensions and Hall's signature dated March 1927, this drawing captures the bespoke aerodynamic engineering that increased aspect ratio and fuel capacity beyond the standard Ryan M-2 design.