Cunningham-Hall Aircraft Corp. formed 1928 at Rochester, NY, concentrating on light civil aircraft: PT-6 6-seat biplane, X-90(N) STOL 2-seater, GA-21M low-wing 2-seater with split trailing edges forming spoilers as well as flaps, GA-36 (improved GA-21) and, in 1937, PT-6F cargo version of company’s original offering.