Sabena from Seaboard World Airlines, using them mainly on transatlantic routes. In the same period, there were experiments with helicopter passenger service using Sikorsky S-58 aircraft from Brussels to Antwerp, Rotterdam, Eindhoven and the Paris heliport at Issy-les-Moulineaux. 1960 saw the introduction of the Boeing 707-320 intercontinental jet for trans-Atlantic flights to New York. SABENA was mainland Europe's first airline to operate a jet across the Atlantic (BOAC had been flying jet transatlantic services using the de Havilland Comet 4 since 4 October 1958). One of Sabena's aircraft became the first Boeing 707 to crash while in commercial service when Flight
Boeing 707 reconnaissance aircraft and the C-137 Stratoliner VIP transports. Boeing produced and delivered 1,011 airliners including the smaller 720 series; over 800 military versions were also produced. As of July 2017, there were no active 707s in commercial airline service. During and after World War II, Boeing was known for its military aircraft. The company had produced innovative and important bombers, from the B-17 Flying Fortress and B-29 Superfortress, to the jet-powered B-47 Stratojet and B-52 Stratofortress. The company's civil aviation department lagged far behind Douglas and other competitors, the only noteworthy airliners being the Boeing 314 Clipper and 307 Stratoliner.