Boeing 747

The first 747-100s were built with six upper-deck windows (three per side) to accommodate upstairs lounge areas. Later, as airlines began to use the upper-deck for premium passenger seating instead of lounge space, Boeing offered a 10-window upper deck as an option. Some -100s were retrofitted with the new configuration.

The idea for The 747SP came from a joint request between Pan American World Airways and Iran Air who were looking for a high capacity airliner with enough range to cover Pan Am's New York-Middle Eastern routes and Iran Air's planned Tehran-New York route. The Tehran-New York route when launched was the longest nonstop commercial flight in the world. The 747SP is 48 feet 4 inches (14.7 m) shorter than the 747-100. Except for the planned 747-8, the SP is the only 747 with a fuselage of modified length. Fuselage sections were eliminated fore and aft of the wing, and the center section of the fuselage was redesigned. Single-slotted flaps replaced the complex triple-slotted Fowler flaps of the 100 series.[112] The under-wing "canoes", which housed the flap mechanisms on full-size 747s, were eliminated entirely on the SP. The 747SP, compared to earlier variants, had a tapering of the aft upper fuselage into the empennage, a double-hinged rudder, and longer vertical and horizontal stabilizers.

The 747SP was granted a supplemental certificate on 4 February 1976 and entered service with Pan American, the launch customer and Iran Air, that same year. The aircraft was chosen by airlines wishing to serve major airports with short runways.

A total of forty-five 747SPs were built. The 44th 747SP was delivered on 30 August 1982. Boeing re-opened the 747SP production line to build one last 747SP five years later in 1987 for an order by the United Arab Emirates government.[113] As of August 2007, 17 Boeing 747SP aircraft were in service with Iran Air (3), Saudi Arabian Airlines, Syrian Arab Airlines (2) and as executive versions. NASA's Dryden Flight Research Center has one modified for the SOFIA experiment.

The 747-300 entered commercial service in 1983, and was the first to integrate the most significant changes of the 747 Classics. These changes included an extended upper deck and improved engines with a reduced fuel burn of 25 percent per passenger. In addition, passenger capacity increased 10 percent by extending the upper deck and relocating the new straight stairway to the rear of the upper deck (prior models had a spiral-shaped staircase in the center of the upper deck). Boeing delivered 81 747-300s in passenger, combi and short-range configurations, the last in 1990.

The most visible difference between the -300 and previous models was a stretched upper deck with two new emergency exit doors and an optional flight-crew rest area immediately aft of the flight deck as standard. (The stretched upper deck had previously been offered as a retrofit and first appeared on two Japanese 747-100 SR models.) Compared to the -200, the upper deck is 23 feet 4 inches (7.11 m) longer than the -200. A new straight stairway to the upper deck instead of a spiral staircase is another difference between the -300 and earlier variants.[69] The staircase creates room below and above for more seats. With minor aerodynamic changes, Boeing increased the cruise speed of the -300 to Mach 0.85 from Mach 0.84 on the -100/-200. The -300 features the same takeoff weight. Two of the three engine choices from the -200 were unchanged in the -300, but the General Electric CF6-80C2B1 was offered instead of the CF6-50E2 offered on the -200.

The 747-300 name, which was proposed for a variant that was never launched, was revived for this new version, which was introduced in 1980. Swissair ordered the first 747-300 on 11 June 1980. The 747-300 first flew on 5 October 1982. Swissair was the first customer to accept delivery on 23 March 1983.

In addition to the passenger version, other versions were available. The 747-300M has cargo capacity in the rear portion of the main deck similar to the -200M, but with the stretched upper deck it can carry more passengers. The 747-300SR is a short range version to meet the need for a high-capacity domestic model. Japan Airlines operated such aircraft with more than 600 seats on the Okinawa–Tokyo route and elsewhere. Boeing never launched a newly built freighter version of the 747-300, but it modified used passenger -300 models into freighters starting in 2000.

A total of 81 aircraft were delivered, 56 for passenger use, 21 -300M and 4 -300SR versions. The 747-300 was soon superseded by the launch of the more advanced 747-400 in 1985, just two years after the -300 entered service. The last 747-300 was delivered in September 1990 to Sabena.

Today, many -300 aircraft are still active, despite a significant loss of interest in the series among large carriers who replaced the 747-300 with the 747-400. Air France and Qantas were some of the last major carriers to operate the 747-300. On 29 December 2008, Qantas flew its last scheduled 747-300 service, operating from Melbourne to Los Angeles via Auckland. On 20 January 2009, Qantas' last 747-300 was flown to the United States for storage. Carriers still using the -300 include Japan Airlines and Saudi Arabian Airlines. Although none were constructed as dedicated freighters, a few -300s have been converted to cargo operations.

The Boeing 747-8 is a widebody commercial airliner being developed by Boeing Commercial Airplanes. Officially announced in 2005, the 747-8 is the latest evolutionary variant of the Boeing 747, with lengthened fuselage, redesigned wings and improved efficiency. With a maximum take-off weight of 970,000 lb (440,000 kg), the 747-8 will be the heaviest aircraft, commercial or military, to be manufactured in the United States.

The first 747-8 freighter is due to be delivered in late 2010, with the passenger model currently scheduled for 2011.

Boeing announced that it was launching the 747 Advanced as the "Boeing 747-8" on 14 November 2005. The 747-8 and 747SP are the only 747 variants with a fuselage of modified length. This will be the first lengthened 747 to go in to production.

The 747-8 will use the same engine and cockpit technology as the 787. Boeing says that the new design will be quieter, more economical, and more environmentally friendly than previous versions of the 747. As a derivative of the already common 747-400, the 747-8 has the economic benefit of similar training and interchangeable parts.

The 747-8, as the current new development of Boeing's largest airliner, is notably in direct competition on long-haul routes with the A380, a full-length double-deck aircraft now in service. For airlines seeking very large passenger airliners, the two have been pitched as competitors on various occasions.

Production of the first 747-8 Freighter began in Everett in early August 2008. On 14 November 2008, Boeing announced a delay to the 747-8 program, citing limited availability of engineering resources within Boeing, design changes and the recent strike by factory workers. Delivery of the first 747-8 Freighter was rescheduled from late 2009 to the third quarter of 2010. The first 747-8 Intercontinental passenger jet delivery was rescheduled from late 2010 to the second quarter of 2011.

As of February, 2009, only one airline customer (Lufthansa) had ordered the 747-8I passenger model, and Boeing announced it was reassessing the 747-8 project. Chief executive Jim McNerney stated that continuation of the project was not a foregone conclusion. The company was assessing various options

The 747-8 is a development of the Boeing 747, which takes advantage of improvements in technology and aerodynamics. The two variants of the 747-8 were launched in 2005, and as of 2006 will both feature a fuselage stretch of 18.3 ft (5.6 m) over the 747-400, bringing the total length to 250 ft 2½ in (76.26 m). The stretch would mean that the 747-8 would be the world's longest passenger airliner, surpassing the Airbus A340-600 by 3.6 ft (1.1 m).

Compared to the 747-400, the main technical changes will be on the wing of the aircraft, which will undergo a complete design overhaul. The sweep and basic structure will be kept to contain costs, but the wing will be thicker and deeper, with the aerodynamics recalculated. The pressure distribution and bending moments will be different, with the new wing for the passenger version being planned to hold 64,225 US gal (243,120 l) of jet fuel, and the cargo aircraft 60,925 US gal (230,630 l). The new wing will have single-slotted outboard flaps and double-slotted inboard flaps. Raked wingtips, similar to the ones currently on the 777-200LR, 777-300ER, and 767-400ER models and the 787-8 and 787-9 design, will replace the winglets on the 747-400. These structures help reduce the wingtip vortices at the lateral edges of the wings, decreasing wake turbulence and drag and thereby increasing fuel efficiency.

The extra fuel capacity in the redesigned wing compared to the 747-400 obviates the need to radically change the horizontal tail unit to accommodate auxiliary tanks, further saving costs. Nonetheless, the vertical tail unit will be raised slightly to 64 feet 2 inches (19.6 m) on the 747-8. Some carbon fiber reinforced plastic will be utilized in the 747-8's airframe to reduce weight; however, structural changes will mostly be evolutionary rather than revolutionary with respect to the 747-400.

The General Electric GEnx, which is one of the two powerplant choices currently offered for the 787, will be the only engine available for the 747-8. However, the 747 variant will be adapted to provide bleed air for conventional aircraft systems and feature a smaller diameter to fit on the 747 wing. An exclusivity agreement between GE and Boeing means that no other manufacturer's engine can be fitted to the 747-8 within at least 10 years.