Question: how old are boeing 747-400?
Answer: The first 747-400 was rolled out on January 26, 1988 and made its maiden flight on April 29, 1988. Type certification was received on January 9, 1989, and it entered service with NWA on February 9, 1989. It retains the 747 airframe, including the 747-300 stretched upper deck, with 6 ft (1.8 m) winglets.