 Following their buyout of Hughes Airwest in 1980, Republic became the largest airline in the U.S. by number of airports served.The company operated the world's largest Douglas DC-9 fleet, with DC-9-10, DC-9-30 and DC-9-50s and also flew Boeing 727-200, Boeing 757-200, and McDonnell Douglas MD-80 jets.In addition, Republic operated Convair 580 turboprops previously flown by North Central.