Air Progress Magazine October 1972

Air Progress Magazine June 1972 Swift Turbo-Charged Conversion Aviation

Mother Earth News Issue 16 1972

Air Progress Magazine January 1972 Erich Hartmann Hippies Flying Aviation

Air Progress Magazine / November 1972 / Homebuilt Aircraft Extravaganza

Air Progress Magazine June 1972

Air Progress Magazine / June 1972 / World's Fastest Swift / Piper Arrow II

Air Progress Magazine / February 1972 / Smyth Sidewinger / Bahamas / Students