The Boeing 747 is a large, wide-body (two-aisle) airliner with four wing-mounted engines. Its wings have a high sweep angle of 37.5° for a fast, efficient cruise speed of Mach 0.84 to 0.88, depending on the variant.
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Aided by a more powerful jet stream than usual, this rapid journey saw the 747 reach a top speed of 825 mph. Photo: Markus Mainka I Shutterstock. Popular Mechanics reports that the reason for it being so powerful on this occasion was a 'bomb cyclone' near Greenland.
The 747-400 is now officially a classic aircraft, and it's an increasingly rare one too. First introduced in 1989, this very successful update to the 747 line is now reaching the end of its life in the skies as operators retire them in favor of newer and more efficient models.
A Boeing 747 can endure about 35,000 pressurization cycles and flights—roughly 135,000 to 165,000 flight hours—before metal fatigue sets in. 747s are retired after approximately 27 years of service.
In the event of an emergency requiring a return to the departure airport, the aircraft circles nearby in order to consume fuel to get down to within the maximum structural landing weight limit, or, if the situation demands, simply land overweight without delay.
Despite quad jets beginning to fall out of favor in the 1980s, the 747-400, which launched in 1988, remains the most popular variant to date, with 694 built until its completion in 2009. Excluding General Electric's testbed jet, 24 747-400 passenger jets remain active, though only ten are in regular passenger service.