George A Spratt

George A. Spratt (1870–1934) was an inventor, aircraft patentee, and the father of George G. Spratt who was also an aircraft designer. Dr. George A. Spratt demonstrated the cable-stayed triangle control frame (TCF) for use in mass-shifting the pilot and pilot holding to control the attitude of a lifting wing for any type of aircraft that could benefit from such arrangement; this arrangement ended up being the sub-assembly most used in these aircraft in the following decades up to contemporary times: hang gliders, powered hang gliders, trikes, and ultralights.

Triangle control frame