Ryan NYP Bare Fuselage Tail Structure and Earth Inductor Compass Bay (Plate #2985) (1927)

Engineering photograph plate 2985 showing uncovered steel-tube tail structure, tail skid, and earth inductor compass mount. — Ryan NYP Bare Fuselage Tail Structure and Earth Inductor Compass Bay (Plate #2985) (1927) · Donald A. Hall Estate Collection

A primary construction photograph (negative plate #2985) documenting the uncovered welded steel-tube empennage and aft fuselage of the Spirit of St. Louis inside the Ryan factory. Against a white backdrop, the image details the longitudinal fuselage longerons, vertical and diagonal tubular braces, control cable guide pulleys, and the pivoting tail skid shock assembly. Mounted atop the upper longeron forward of the vertical fin post, the photograph clearly shows the installation cylinder and vertical drive mast for the Pioneer Earth Inductor Compass generator, documenting Hall's structural accommodation of this navigation instrument.