The Boeing 747-400 is a jet airliner, a variant of the Boeing 747. Compared to the original 747, the 747-400 features improvements such as more powerful engines, new avionics, a new interior, and a longer-span wing with winglets. The 747-400 first flew in 1988 and entered service in 1989. It was produced until 2009 in six different variants: 747-400, 747-400F, 747-400M, 747-400D, 747-400ER, and 747-400ERF.