747 Sunset

A Boeing 747-400 lands at sunset on Runway 27R at London Heathrow Airport. Derived from the earlier versions of the Boeing 747, the 747-400 retains the four-engine wide-body layout of its predecessors, whilst incorporating numerous technological and structural changes to produce a more efficient airframe. Its most distinguishing features versus preceding 747 models are 6-foot (1.8 m) winglets mounted on 6-foot (1.8 m) wing tip extensions, which are found on all 747-400s except for Japanese domestic market versions. It is the best-selling model of the Boeing 747 family of jet airliners - the first 747-400 came into service in 1989 with KLM. 

A 747-400 typically takes off at 290km/h (180mph), cruises at 910km/h (565mph) and lands at 260km/h (160mph). The 747-400's wingspan was stretched by 17 feet (5.2 metres) over the Classic 747 through wingtip extensions. For reduced aerodynamic drag, the wings were fitted with 6 feet (1.8 metres)-tall winglets.[13] Despite the added length, the wings were 6,000 pounds (2,700 kg) lighter as a result of new aluminum alloys.

The 747-400's leasing, resale and salvage value has dropped steeply because it is relatively expensive to operate. As many 747-400s are now more than 20 years old, airlines are beginning to replace them. Airlines using the 747-400 have accelerated its retirement (as of 2015) and are replacing the model with more fuel efficient aircraft. The main appeal of the 747-400 like its predecessors was its range rather than its capacity, and in many cases it has been replaced by wide-body twin-engine aircraft of similar range, such as the Boeing 777 and Boeing 787 Dreamliner.