Sabena served by the airline. Sabena used landplanes for its Congo operations and a program of aerodrome construction was initiated in the Congo. This was finished in 1926 and Sabena immediately began flights within the Belgian colony, the main route being Boma-Léopoldville-Élisabethville, a 2,288 km (1,422 mi) route over dense jungle. First, flights were operated with De Havilland DH.50s, although these were quickly replaced by the larger Handley Page W.8f which had three engines and offered ten seats. By 1931 Sabena's fleet, including the aircraft used on the Congo network, totalled 43 aircraft. Its mainstay type was the Fokker F.VIIB with
National Airline History Museum Martin 4-0-4s built. TWA operated 40 in their fleet along the U. S. east coast, while strong competitor Eastern Airlines operated the largest 4-0-4 fleet, flying 60 aircraft along that airline's eastern seaboard route, including in and around Florida. The museum's Martin 4-0-4 has not flown in years. As part of the National Airline History Museum’s reorganization plan, which began in 2011, a maintenance inspection of the Martin 4-0-4 was completed in August 2011 to determine the feasibility of returning the aircraft to flying status. Rumors of extensive corrosion and insurmountable mechanical problems were found to be untrue, and a