Today's long haul - and for that matter, 'big jet' shorter routes - are fast becoming, or even have already become, the preserve of twin-engine airliners. But it was not always so; as the 1960s drew to a close, aviation thinking and practice demanded four engines for long haul (as Virgin Atlantic once put it).
With the help of a number of aviation photographers from around the world, we look back at the three aircraft that heralded the start of wide-bodied airliner travel.
(above - the airline that started it all: Pan Am: Piergiuliano Chesi)
The Boeing 747
Pan Am were synonymous with the 747 and operated a number of their early aircraft right from delivery until the airline's closure in 1991.
Above: Clipper Ocean Telegraph, upon which the author made his first flight on a 747 between London Heathrow and New York John F. Kennedy (Kambui).
Below: Clipper Neptune's Car, also flown on by the author, this time on the reverse journey, although the aircraft was in the earlier paint scheme at the time before being repainted into the airline's final scheme (Konstantin von Wedelstaedt).
Trans World Airlines were the second airline to take delivery of the 747, although the first flight was a US transcontinental service before the airline deployed the aircraft on to international routes (Michel Gilliand)
Above: pictured at a muggy Los Angeles, like most of the big US carriers, Continental took delivery of the 747 before disposing of their fleet. The big Boeing made a comeback with the airline when it began Transatlantic services however (Clipper Arctic).
The only US airlines to consistently operate the 747 from start to finish were Pan Am, TWA, Northwest and - above - United. All four airlines saw the type fly in every colour scheme used by the carriers and United used the -100, -200 and -400 sub-types, as did Northwest (Jon Proctor).
Above: the end is nigh: United 747s share storage areas at Victorville with the smaller Boeing 767 and Delta L1011 TriStars (Konstantin von Wedelstaedt).
Below: a curiosity - Eastern leased three of Pan Am's aircraft for use on the New York to Miami route and subsequently arranged to buy this one from Qantas. Seen at Sydney, despite painting the aircraft in EA's colours and gaining a US registration, the sale fell through and it was never delivered to the American carrier (Daniel Tanner)
Above: BOAC's initial 747-136s sat at Heathrow for a while in 1970 due to a pay dispute with the airline's pilots. Once in service however, most of the early 747s stayed in use for the duration of their service lives and were seen in both the first and the later British Airways colours (Clipper Arctic)
The Lockheed L1011 TriStar
Below: Like American, Delta and others, Eastern found the 747 too large and went for the Lockheed L1011 Tristar in big numbers (Jon Proctor).
Above: TWA were also an early customer and, like the 747, operated the tri-jet in this colour scheme and the subsequent designs until the carrier was merged into American Airlines (Clipper Arctic)
Below: Delta ultimately became the biggest operator of the L1011, using the longer range TriStar 500 to pioneer its development as an intercontinental airline (Aero Icarus).
Above: Like Delta, British Airways found a use for both the shorter range version as well as the TriStar 500. Ordered originally by British European Airways (BEA) by the time the first aircraft was delivered, both BEA and BOAC had become British Airways (Michel Gilliand).
The Douglas DC-10
American Airlines were at the forefront of the design for the Douglas DC-10 and eventually operated over 50 of the US domestic DC-10-10.
The aircraft suffered from some design problems early in its life and was the subject of a worldwide grounding at one point.
Nevertheless, the DC-10 went on to have a highly successful career with airlines around the globe. The type also played a significant role in developing the US giant's international services, although the airline's DC-10-30s were all second hand. Only eight of the long-range tri-jets were operated as the Boeing 767 was being introduced as American expanded and the airline found the twin-jet a better fit.
(left: Clipper Arctic).
(Below: Christian Hanuise)
Above: Northwest were also an enthusiastic user of the Douglas jet, operating the DC-10-10, the -30 and the -40, one of only two airlines to order the latter version. Japan Air Lines was the other (Michel Gilliand).
Below: Two airlines not usually associated with the DC-10 were Eastern and Pan Am. The former acquired three ex-Alitalia examples to operate its new Miami-London Gatwick service but the route was not a success and the aircraft were redeployed on South American routes until they were disposed of (Ken Fielding).
Pan Am acquired both the -10 and -30 as a result of the merger with National Airlines but did not use the type for long as the airline already had L1011-500s in service (Clipper Arctic)
And on in to the future...
Both the L1011 and the DC-10 are now absent from passenger service around the world and the 747 will soon join them. The introduction of the Boeing 767 paved the way for twin-engine operations but once the Boeing 777 and Airbus A330 had established themselves, the economics of the newer aircraft, as well as better noise and emission qualities, has meant the pioneers of wide-body airliner travel are fading into the memories of the past.
As well as the 777, new types like the Boeing 787 Dreamliner and the Airbus A350 now have the range and reliability for most airlines worldwide.
(below - Kevan James)
With grateful thanks to photographers everywhere for recording the aircraft that graced the skies and airports around the world.
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