Ryan NYP Flight Endurance Calibration: Gross Weight vs. Flight Time (1927)

Engineering graph plotting gross weight and fuel consumption against elapsed flight time in hours. — Ryan NYP Flight Endurance Calibration: Gross Weight vs. Flight Time (1927) · Donald A. Hall Estate Collection

A primary technical calculation graph from Donald A. Hall Sr.'s files plotting gross aircraft weight and fuel burn against elapsed flight time in hours. The chart tracks the continuous weight reduction of the Spirit of St. Louis from 5,130 pounds at takeoff down to empty reserve weight across an endurance envelope extending beyond 40 hours. This mathematical projection proved that the Ryan NYP possessed sufficient fuel capacity to overcome head winds, bad weather detours, and navigational drift.