All Topics  
Trijet

 
Trijet

 
   Email Print
   Bookmark   Link
 

 

Trijet
 
 
  Topics Trijet Topic Home

A trijet is an aircraft
Aircraft

An aircraft is a vehicle which is able to flight by being supported by the air, or in general, the atmosphere, of a planet. Examples include balloons, airplanes and helicopters....
 powered by three jet engine
Jet engine

A jet engine is a reaction engine that discharges a fast moving jet of fluid to generate thrust in accordance with Isaac Newton Newton's laws of motion....
s. Early twin-jet designs were limited by the FAA
Federal Aviation Administration

The Federal Aviation Administration is an agency of the United States Department of Transportation with authority to regulate and oversee all aspects of civil aviation in the U.S....
's " 60-minute rule
ETOPS/LROPS

ETOPS is an acronym for Extended-range Twin-engine Operational Performance Standards, an International Civil Aviation Organization rule permitting twin-engined commercial air transporters to fly routes that, at some points, are farther than a distance of 60 minutes' flying time from an emergency or diversion airport with one engine ino...
", whereby the flight path of twin-engined jetliners was restricted to within 60 minutes' flying time from a suitable airport, in case of engine failure. In 1964 this rule was lifted for trijet designs, as they had a greater safety margin. This led to a flurry of trijet designs, which by 1980 had become the most popular airliner configuration.

Generally, passenger airline
Passenger airline

A passenger airline is an airline dedicated to the transport of passengers. Cf. cargo airline. Passenger airlines usually operate a fleet of passenger aircraft which, rather than being owned outright, are usually leased from Commercial Aircraft Sales and Leasing companies such as GECAS and ILFC....
 trijets are considered to be second generation jet airliner
Jet airliner

A jet airliner is a passenger airplane that is powered by jet engines. This term is sometimes contracted to jetliner.In contrast to today's relatively fuel-efficient, turbofan-powered air travel, first generation jet airliner travel was noisy and fuel inefficient....
s, due to their innovative engine locations, in addition to the advancement of "fanjet" technology.

Other variations of three-engined designs are trimotor
Trimotor

A trimotor is an aircraft powered by three piston engines. An aircraft with three jet engines is a trijet.Trimotor designs were relatively common in the early days of aviation, as engines were less powerful and less reliable....
s, which are aircraft with three piston engines.

History
During the late 1970s and early 1980s, three was the most common number of engines on US jet airlines, making up a majority of all such aeroplanes in 1980.






Discussion
Ask a question about 'Trijet'
Start a new discussion about 'Trijet'
Answer questions from other users
Full Discussion Forum



Encyclopedia


A trijet is an aircraft
Aircraft

An aircraft is a vehicle which is able to flight by being supported by the air, or in general, the atmosphere, of a planet. Examples include balloons, airplanes and helicopters....
 powered by three jet engine
Jet engine

A jet engine is a reaction engine that discharges a fast moving jet of fluid to generate thrust in accordance with Isaac Newton Newton's laws of motion....
s. Early twin-jet designs were limited by the FAA
Federal Aviation Administration

The Federal Aviation Administration is an agency of the United States Department of Transportation with authority to regulate and oversee all aspects of civil aviation in the U.S....
's " 60-minute rule
ETOPS/LROPS

ETOPS is an acronym for Extended-range Twin-engine Operational Performance Standards, an International Civil Aviation Organization rule permitting twin-engined commercial air transporters to fly routes that, at some points, are farther than a distance of 60 minutes' flying time from an emergency or diversion airport with one engine ino...
", whereby the flight path of twin-engined jetliners was restricted to within 60 minutes' flying time from a suitable airport, in case of engine failure. In 1964 this rule was lifted for trijet designs, as they had a greater safety margin. This led to a flurry of trijet designs, which by 1980 had become the most popular airliner configuration.

Generally, passenger airline
Passenger airline

A passenger airline is an airline dedicated to the transport of passengers. Cf. cargo airline. Passenger airlines usually operate a fleet of passenger aircraft which, rather than being owned outright, are usually leased from Commercial Aircraft Sales and Leasing companies such as GECAS and ILFC....
 trijets are considered to be second generation jet airliner
Jet airliner

A jet airliner is a passenger airplane that is powered by jet engines. This term is sometimes contracted to jetliner.In contrast to today's relatively fuel-efficient, turbofan-powered air travel, first generation jet airliner travel was noisy and fuel inefficient....
s, due to their innovative engine locations, in addition to the advancement of "fanjet" technology.

Other variations of three-engined designs are trimotor
Trimotor

A trimotor is an aircraft powered by three piston engines. An aircraft with three jet engines is a trijet.Trimotor designs were relatively common in the early days of aviation, as engines were less powerful and less reliable....
s, which are aircraft with three piston engines.

History


During the late 1970s and early 1980s, three was the most common number of engines on US jet airlines, making up a majority of all such aeroplanes in 1980. From 1985 to 2003 the number of such planes in service has sunk from 1488 to 602. The number of twin-jets has more than quadrupled in the same period.

A real disadvantage with trijets is positioning the central engine. On most trijets they are placed at the tail along the middle, producing some technical difficulties. A "straight" layout such as the DC-10 and MD-11 leaves the engine high above the ground, making access difficult. Another option is an S-shaped duct
S-duct

An S-duct is a unique type of jet engine intake duct, used only on trijet aircraft. The S-duct is located in the tail, or empennage, of the aircraft....
 like that found on the Boeing 727, Tupolev 154 and Lockheed Tristar, which is a complicated and costly design. One major advantage of the trijet design is that the wings can be located further aft on the fuselage, allowing main cabin exit and entry doors to be more centrally located for quicker embarkation and disembarkation, ensuring faster turnaround times.

With ETOPS restrictions eased, twijets became more suitable for long-haul overwater operation. With modern engines having extremely low failure rates and increased power output, more than two engines are no longer necessary except for "very large aircraft
Jumbo jet

The Boeing 747The Boeing 747 was the original jumbo jet. The 747 was the first wide-body airliner, first to use the twin-aisle concept, and the first airliner to use high bypass turbofan engines....
," such as the Airbus A340-600, Airbus A380
Airbus A380

The Airbus A380 is a Double-deck aircraft, wide-body, four-engine jet airliner manufactured by the European corporation Airbus, a subsidiary of EADS....
 or Boeing 747
Boeing 747

The Boeing 747 is a wide-body aircraft commercial airliner, often referred to by the nickname "Jumbo Jet". It is among the world's most recognizable aircraft, and was the first widebody ever produced....
.

MDC
McDonnell Douglas

McDonnell Douglas was a major American aerospace manufacturer and defense contractor, producing a number of famous commercial and military aircraft....
 was planning a new series of DC-10
McDonnell Douglas DC-10

The McDonnell Douglas DC-10 is a trijet medium- to long-range widebody airliner, with two engines mounted on underwing pylons and a third engine at the base of the vertical stabilizer....
 family trijets called the MD-XX (Lengthened versions of the MD-11
McDonnell Douglas MD-11

The McDonnell Douglas MD-11 is an American trijet medium to long-range wide-body aircraft airliner, with two engines mounted on underwing pylons and a third engine at the base of the vertical stabilizer....
). The MD-XX Long Range would have been capable of travelling distances up to 8,320 nautical mile
Nautical mile

A nautical mile or sea mile is a unit of length. It corresponds approximately to one minute of arc of latitude along any meridian .It is a non-International System of Units unit used especially by navigators in the shipping and aviation industries....
s and a wing span of 213 feet. The project was cancelled in 1996, one year before McDonnell Douglas merged with Boeing.

Current Status


Today, both narrow-body
Narrow-body aircraft

A narrow-body aircraft is an airliner with a fuselage aircraft cabin diameter typically of 3 to 4 metres , and airline seat arranged 2 to 6 abreast along a single aisle....
 and wide-body trijet production has ceased for commercial aircraft, being replaced by twinjet
Twinjet

A twinjet is a jet aircraft powered by two jet engines. There are two common configurations of the engines; one sees either engine slung under a wing, and the other sees them mounted at the back of the fuselage....
s which are quieter and more efficient. The trijet design is currently only built on the Dassault Falcon 7X
Dassault Falcon 7X

The Dassault Falcon 7X is a France-built large-cabin, long range business jet manufactured by Dassault Aviation, the flagship offering of their business jet line....
 and the Dassault Falcon 900 business jets, which both feature S-duct
S-duct

An S-duct is a unique type of jet engine intake duct, used only on trijet aircraft. The S-duct is located in the tail, or empennage, of the aircraft....
s.

Classification of trijets by use, size and production


name (type)classmain useoperation periodproduction period length in m (minimum-maximum) wing span in m (minimum-maximum)number produced (until mid 2008) number in service and parked (mid 2008)country image
Boeing 727
Boeing 727

The Boeing 727 is a mid-size, Narrow-body aircraft, trijet, T-tailed Commercial airliner jet airliner. The 727's fuselage has an outer diameter of ....
 narrow-body civil in service 1963-1984 40 m - 46 m 32 m 1.832 838
Boeing C-22
Boeing C-22

The Boeing C-22 was a US military version of the Boeing 727. The C-22B, a Boeing 727, was the primary medium-range aircraft used by the Air National Guard and National Guard Bureau to airlift personnel....
 narrow-body military in service 1963-1984 40 m 33 m 4 1
Dassault Falcon 50
Dassault Falcon 50

The Dassault Falcon 50 is a France-built super mid-sized, long-range corporate Jet aircraft, featuring a three jet engine layout with an S-duct central engine....
 business jet civil in service 1976-2008 18 m 18 m 352
Dassault Falcon 900 business jet civil in service 1984- 20 m 19 m 260
Dassault Falcon 7X business jet civil in service 2001- 23 m 25 m 
Hawker Siddeley Trident
Hawker Siddeley Trident

The Hawker Siddeley Trident, model DH121 or HS121, was a United Kingdom short/medium-range trijet airliner designed by de Havilland in the 1950s, and built by Hawker Siddeley in the 1960s, after the former became part of that group in 1960....
 (de Haveland)		 narrow-body civil out of service 1950er-1971 (ca.) 35 m - 40 m 27 m - 29 m 117 --
Lockheed L-1011 Tristar wide-body civil in service 1970-1984 50 m - 54 m 47 m - 50 m 250 90
Lockheed K1/KC1/C1
Lockheed TriStar (RAF)

The Lockheed TriStar is an aerial refueling and transport aircraft in service with the Royal Air Force. All were converted from civilian Lockheed L-1011 airliners....
 wide-body military in service 1970-1984 50 m - 54 m 47 m - 50 m 9 6
McDonnel Douglas DC-10 wide-body civil in service 1968-1988 55 m 47 m - 50 m 386 213
McDonnel Douglas KC-10 Extender wide-body military in service 1979-1990 55 m 50 m 60 60
McDonnel Douglas MD-11 wide-body / cargo civil in service 1988-2000 61 m 51 m 200 195
Tupolew Tu-154 "Careless" narrow-body civil in service 1968-2006 48 m 37 m 915 470 (former )
Yakovlev Yak-40
Yakovlev Yak-40

File:Lineup of Yak-40 at Zhulyany Airport.jpegThe Yakovlev Yak-40 is a small, trijet airliner that is often called the first regional jet transport aircraft....
 business jet civil in service 1967-1981 20 m 25 m 1.011 731 (former )
Yakovlev Yak-42
Yakovlev Yak-42

The Trijet Yakovlev Yak-42 was designed as a replacement for the twin engined Tupolev Tu-134 Jet aircraft as a mid-range passenger jet. The Yak-42 was also the first airliner to be produced in the Soviet Union to be powered by modern high-bypass turbofan engines....
 "Clobber"		 narrow-body civil in service 1979-2002 36 m 34 m 184 158 (former )


Future of trijets


Airbus has filed a patent for a new, twin-tail trijet design, but it is unknown if this will ever come to market.

Proposed or suspended trijet developments


  • Boeing 747-300 Trijet
    Boeing 747

    The Boeing 747 is a wide-body aircraft commercial airliner, often referred to by the nickname "Jumbo Jet". It is among the world's most recognizable aircraft, and was the first widebody ever produced....
    : never produced.
  • Blended Wing Body Trijet
  • McDonnell Douglas MD-XX: never produced.
  • Airbus twin-tail trijet, status unknown.
  • Dassault Supersonic Business Jet (suspended)


See also


  • Twinjet
    Twinjet

    A twinjet is a jet aircraft powered by two jet engines. There are two common configurations of the engines; one sees either engine slung under a wing, and the other sees them mounted at the back of the fuselage....
  • S-duct
    S-duct

    An S-duct is a unique type of jet engine intake duct, used only on trijet aircraft. The S-duct is located in the tail, or empennage, of the aircraft....
  • Wide-body aircraft
    Wide-body aircraft

    A wide-body aircraft is a large airliner with two passenger aisles, also known as a twin-aisle aircraft. The typical fuselage diameter is 5 to 6 metres ....