The 747-400 is the latest, longest ranging and best selling model of the 747 family.
Boeing launched the 747-400 in October 1985 and the first development aircraft first flew on April 29 1988. US certification (with PW-4000s) was awarded in January 1989.
The 747-400 externally resembles the -300, but it is a significantly improved aircraft. Changes include a new, two crew digital flightdeck with six large CRT displays, an increased span wing with winglets (the -400 was the first airliner to introduce winglets), new engines, recontoured wing/fuselage fairing, a new interior, lower basic but increased max takeoff weights, and greater range.
Apart from the basic passenger 747-400 model, a number of variants have been offered including the winglet-less 747-400 Domestic optimised for Japanese short haul domestic sectors, the 747-400M Combi passenger/freight model, and the 747-400F Freighter (which combines the 747-200F's fuselage with the -400's wing).