The de Havilland DH 106 Comet was the first production commercial jetliner. The Avro Tudor and Vickers VC.1 Viking was fitted with Rolls-Royce Nene turbojets. It had flown earlier but were experimental models. The jet was made by de Havilland at its Hatfield Aerodrome, Hertfordshire, United Kingdom headquarters. The prototype first flew on 27 July 1949. It featured an aerodynamically clean design with four de Havilland Ghost turbojet engines buried in the wings. It had a pressurised fuselage. The jet had large square windows. It showed signs of being a commercial success at its 1952 debut.