Donald A. Hall Estate Collection

Ryan NYP Center of Gravity Leveling Test Profile on Test Stand (1927)

An archival master negative print documenting the weight-and-balance testing of the Spirit of St. Louis at Dutch Flats, San Diego. The aircraft's tail is hoisted onto an adjustable vertical trestle stand to establish a level flight attitude. Donald A. Hall Sr. utilized this test rig with floor scales to measure baseline wheel loads and calculate the longitudinal center of gravity across various fuel configurations.