Donald A. Hall Estate Collection

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

A vintage positive slide made from Donald Hall's primary negative collection, recording the weight-and-balance testing of the Ryan NYP at Dutch Flats in late April 1927. The aircraft's tail skid is hoisted atop an adjustable test trestle to bring the fuselage into level flying attitude. By placing mechanical platform scales beneath each landing wheel and the tail trestle, Hall measured empty weight wheel reactions, calculated the baseline longitudinal center of gravity, and mapped the shifting CG envelope across varying fuel loads up to 425 gallons.