What Killed the Trijets?

once a staple of commercial aviation the tri-check configuration of airliner was one that formed the backbone of nearly all major carriers from the dawn of the jet age right up until the new millennium but despite their iconic look rising fuel prices and improved technology gradually saw this once common part of the airliner scene be whittled away to just a few surviving members now having disappeared almost completely from the northern hemisphere to popular belief the world's first aircraft to adopt a tri-chet engine layout was not the hawker city trident of the 1960s but instead the chupalev tu-73 naval bomber prototype built in 1947 which fitted two engines in pods beneath the wings and a third engine mounted in the tail the choice of three engines being due to concerns by soviet designers as to the abilities of contemporary turbo jets to power an aircraft of such size and weight indeed the predominant concern that necessitated the fitting of more than two engines as had been the case with preceding propeller-driven airliners in the pre-war and post-war era was an uncertainty as to the reliability of emerging power plants and that in the event of a mechanical failure or emergency an aircraft had to be guaranteed the ability to safely reach an airport on less than its full complement of engines by 1953 jet-powered air travel was restricted solely to the four-engine de havilland comet of britain and the experimental avro canada c-102 jetliner therefore the only measures by which the potential reliability of upcoming jet engine designs was based almost entirely on the performance of propeller-driven airliners and thus in that same year the federal aviation administration or faa enacted the 60-minute rule which limited the potential range of twin-engine commercial aircraft flying over large bodies of water to within 60 minutes of a suitable airport essentially ruling out the possibility of twin jets filling a role other than domestic or regional airliners meanwhile four-engined aircraft were largely the norm when it came to air travel in the 1950s the lockheed constellation and douglas dc-6 being the face of luxurious new vacation and commuter corridors that were gradually expanding across the globe this mindset being carried over into the first generation of jet airliners in the form of the boeing 707 douglas dc-8 and the aforementioned comet presenting a perfect mixture of performance and redundancy during the pioneering early days of the jet age one problem that emerged during this period though was a significant level of inefficiency with regard to utilizing four engines the 707 and dc8 being heavy on fuel consumption and noise therefore the concept of creating a more economic alternative was set down early on but one that would avoid the use of twin jets due to the ever-present 60-minute rule the only twin-jet model to be released during the first decade of the jet age being the sudaviashon carvel of france which was limited to the role of a domestic airliner it wouldn't be until 1962 though that the world's first commercial tri-jet would be released in the form of the hawker sidley trident of britain an airliner that adopted three engines by stipulation of prospective main customer british european airways or bea who demanded threat jets in order to provide a suitable trade between cruising speed and mechanical redundancy the aircraft after seeing a turbulent and disjointed development undertaking its maiden flight on january 9th of that year at the same time america was developing its own domestic airliner as the boeing 727 an aircraft that was designed to meet the demands of carriers united airlines american airlines and eastern airlines who wish to open up jet-powered air corridors to smaller cities with facilities or demand too small to either handle or justify the use of the larger boeing 707 the company's stock gap the boeing 720 creating a short-bodied short-range version of the airliner with a lower take-off weight but saw limited success the reason for using three engines with the 727 came down to a compromise between the three carriers that were pivotal in its inception with united requiring four engines for use at high altitude fields such as denver stapleton american wishing to have a twin jet for fuel efficiency purposes and easton demanding a tri-jet so as to permit operation on their popular caribbean services without incurring the limitations of the faa's 60-minute rule while the trident thanks to its highly advanced but complicated design which was built to solely suit the needs of bea failed to garner competitive sales outside of the uk the boeing 727 took the global aviation market by storm thanks to its superb mixture of efficiency performance and safety and with no other competitive models available on the short to medium range market the model was quickly able to find a place in the fleet of nearly every major carrier on earth while the boeing 727 and trident emerged in the western world the soviet union was also fond of trijet designs creating multiple three-engine models throughout the 1960s starting with the yakovlev yak-40 in 1967 a short-range regional jet which was built to compete with the likes of the fokker f-28 adopting three engines against the fockers 2 for the purposes of reliability and safety this was followed in 1968 by the chupalev tu-154 a medium-range tri-jet which was slightly larger than the 727 and trident and intended to complement the four-engined long-range illusion il-62 in the soviet union's commercial airliner hierarchy by providing a more efficient and high performance aircraft factors which would secure its future among carriers of the eastern bloc during the fuel embargoes implemented against the soviet states during the later years of the cold war by the dawn of the 1970s though the face of commercial aviation was changing again this time with the advent of wide-body airliners this new era of air travel being brought about when boeing took what was previously an unsuccessful proposal for a large military transport aircraft for the us air force and converted it into a passenger airliner known as the iconic boeing 747 its ability to carry up to 350 passengers opening up air travel to the mass market the development of the boeing 747 though have been known within the airliner industry since as early as 1965. therefore the company's rivals had ample time to undertake the development of a competitive model the newly formed mcdonald douglas being in a similar situation to boeing in that they had unsuccessfully partaken in the proposed new military transport contract which was later evolved into a four-engine double-deck airliner similar in size to the preceding douglas dc-8 the incentive to convert the design from a quad jet to a tri jet came through the intervention of american airlines in 1966 when after consultation with douglas as to their proposed wide-body jet showed a preference to an airliner that was capable of flying similar long-range routes from airports with shorter runways thereby opening up a wider variety of travel corridors than what could be achieved with the boeing 747 meanwhile lockheed who had won the military transport contract with their c5 galaxy was a relatively small player in the world of 1960s commercial aviation as while it had seen massive success with the iconic constellation of the 1940s and 50s their latest model the l188 elektra turboprop was quickly being rendered obsolete as jets like the boeing 727 came in to sweep up its role the firm being able to make money through the sale of its vast arsenal of military models like the c-130 hercules following the start of boeing 747 development in 1965 lockheed were eager to return to commercial aviation and thus announced their intention to build a three-engined wide-body airliner which would be based on similar principles and motivations as the proposed douglas model the main differences between the two prospective wide-body trijets being lockheed's emphasis on introducing cutting-edge technology wherever possible in order to be more efficient and by extension attractive than its rival the result was two trijet models that took their respective first flights within two months of each other during late 1970. the douglas dc-10 and the lockheed l-1011 tristar the main differences between the two being the design of the third engine the dc-10 adopting a straight-through turbofan engine while the tristar used a more traditional s-duct which integrated the power plant into the rear fuselage the s-duct presenting less drag as it complemented the profile of the airliner while a straight-through configuration though incurring a drag penalty was easier to install maintain and replace though it appeared the tristar and dc10 would enter service at the same time lockheed would dealt a severe blow following the bankruptcy of its sole engine provider rolls royce on february 4th 1971 the firm having been responsible for the development of a brand new turbofan engine for the airliner in the form of the rb211 but due to early mismanagement which began heavy spiraling costs the project ultimately led to the company's financial collapse and subsequent nationalization by the british government with the tri-star now severely delayed the dc-10 leapt into the lead and quickly became a sales success upon its launch in august 1971. the airliner's mixture of high capacity though less than the 747 greater efficiency and better short field performance making it extremely popular among carriers across the world helped further by the impact of the 1973 oil crisis which put efficiency as the highest priority of airlines with this tri-jets remained an important choice for carriers despite their reputation being rumbled by an endemic cargo door fault in the dc-10 which resulted in a series of horrendous crashes and a bribery scandal with the l-1011 that saw several members of the japanese government indicted on corruption charges but soon a newly formed european multinational aircraft builder named airbus would present an efficient alternative that rapidly spelled doom for the future of the tri-jet six months after the launch of the tristar into commercial service in april 1972 airbus following nearly a decade of development performed the first flight of their pioneer model the a300 a wide-body twin jet with a ranging capacity that was easily comparable to america's tri-jets but presented efficiency that was far greater than anything the dc10 or the tri-star could accomplish while initially hamstrung by the faa 60 minute rule once the a300 had begun to prove itself on routes across large bodies of water where the faa rule didn't apply specifically on the far eastern and asian markets american carriers quickly began to appreciate that the new twin jet was a viable alternative to the tristar or dc-10 and thus lobbied for the outdated 60-minute rule to be revoked and replaced by an updated regulation for twin jet aircraft the result was e-tops or extended range twin-engine operations performance standards which was introduced in 1977 and extended the potential flight time of a twin jet over water on a single engine to 90 minutes opening up the transatlantic corridor to the a300 and seeing early sales of the type among u.s carriers including eastern airlines and pan am etops was therefore the beginning of the end for the tri-jet and with sales continuing to slump for the dc-10 and tristar by the end of the 1970s both models were phased out of production for the passenger market by the middle of the 1980s the tri-star leaving production in 1984 while the dc-10's last passenger orders came in 1982 after which the model remained in production solely as a cargo aircraft or as the kc-10 aerial tanker although douglas had briefly revived an earlier concept to create a twin-jet version of the airliner though this never went beyond the drawing board instead the company made one last attempt to reinvigorate sales in their tri-jet model through the dc-10 super 60 project an enlarged version of the previous dc-10 which improved the overall design through all manner of modern flight instrument systems and design aspects including the fitting of winglets to improve lift and reduce fuel consumption the goal of the super 60 being to bridge the gap between twin jets and quad jets by providing range performance and capacity superior to the a300 taking its first flight in 1988 after nine years of planning and development the mcdonald douglas md-11 was to be the pinnacle of trijet technology but ultimately failed to win over customers thanks to a mixture of less than advertised range and fuel efficiency while also completely misreading the trends for twin jet airliners that had now come to dominate the 1980s before the md-11 project was officially launched in 1986 etops regulations had been increased to 120 minutes a year earlier and before that boeing had developed a series of twin jet competitors to fight the airbus a300 on the grounds of efficiency creating the boeing 767 wide body of 1982 and the boeing 757 narrow body of 1983 which replaced the boeing 727 after 22 years of production while airbus continued to press on with twin jet proposals including the airbus a310 of 1983 and the prospective airbus a330 project scheduled for delivery by the early 1990s therefore by the time the md-11 entered commercial service in 1990 it was truly a relic of a bike on age in aviation its capacity and range improvements over the a300 and 767 quickly being quashed by the introduction of the airbus a330 in 1992 and the boeing 777 in 1995 two twin jet airliners that had range in capacity that matched the nd-11 but still had fuel efficiency that far exceeded douglas's tri jet the md-11 therefore was the last commercial tried yet to be released its sales collapsing in the face of the far more successful a330 and 777 which ultimately forced mcdonald douglas into bankruptcy the company being purchased and merged into the ranks of rivals boeing in august 1997 during a 13 billion dollar stock swap the airliner remaining in production solely as a cargo aircraft before seeing discontinuation in october 2000 bringing an end to the era of the tri-jets the chupaolev tu-154 remained in production until 2013 and with dc-10s tristars md-11s and boeing 727s still being prominent on the airliner stage by the turn of the new millennium the fallout of the post-9 11 airline market crash as well as fuel spikes and a drive within the aviation industry to develop more efficient aircraft the widespread use of tri-jets rapidly waned during the 2000s and by 2010 most heritage trijets had been retired from frontline service the last major passenger carriers to use tri-jets being klm and bayman bangladesh airlines who retired their last md-11s and dc-10s respectively in 2014. by the start of the 2020s though the trijet isn't completely extinct in the airliner world md-11s and dc-10s continuing to play a pivotal role for cargo carriers including fedex and ups while the only company that continues to manufacture a three-engined aircraft for civilian use is french builder dassault and its range of falcon private jets to summarize the existence of the tri-jet was rooted solely in the creation of the 60-minute rule by the faa and in that same manner was rendered obsolete when the rule was revoked in the 1970s as twin jets began to move in and undercut the three-engine design philosophy the desire by builders and carriers to introduce more efficient aircraft in the wake of the many oil crises and market crashes pushing the likes of the 727 dc10 and tristar rapidly out of favor you

Channel: Ruairidh MacVeigh

Views: 441,440

Keywords: Airbus, Boeing, Air, Aircraft, Airplane, Aeroplane, Airliner, Commercial Airliner, Airline, Airlines, Airways, International Airline, International, International Airport, Departure, Arrival, Take-off, Landing, Flight, Flying, Plane, Runway, Approach, Terminal, Boeing 727, Boeing 747, Boeing 757, Boeing 767, Boeing 777, Douglas, McDonnell Douglas, DC-10, MD-11, Lockheed, Lockheed Tristar, Lockheed L-1011, Hawker Siddeley, Hawker Siddeley Trident, Trident, Tupolev Tu-154, Trijet, Three Engines, Three Hole

Id: p5b723gkoC8

Length: 14min 52sec (892 seconds)

Published: Sat May 15 2021