Turbofan in the context of "Jet engines"

The McDonnell Douglas DC-10 is an American trijet wide-body aircraft manufactured by McDonnell Douglas.The DC-10 was intended to succeed the DC-8 for long-range flights. It first flew on August 29, 1970; it was introduced on August 5, 1971, by American Airlines.

The trijet has two turbofans on underwing pylons and a third one at the base of the vertical stabilizer.The twin-aisle layout has a typical seating for 270 in two classes.The initial DC-10-10 had a 3,500-nautical-mile [nmi] (6,500 km; 4,000 mi) range for transcontinental flights. The DC-10-15 had more powerful engines for hot and high airports. The DC-10-30 and –40 models (with a third main landing gear leg to support higher weights) each had intercontinental ranges of up to 5,200 nmi (9,600 km; 6,000 mi). The KC-10 Extender (based on the DC-10-30) is a tanker aircraft that was primarily operated by the United States Air Force.

The Boeing 747 is a long-range wide-body airliner designed and manufactured by Boeing Commercial Airplanes in the United States between 1968 and 2023.After the introduction of the 707 in October 1958, Pan Am wanted a jet 2+1⁄2 times its size, to reduce its seat cost by 30%. In 1965, Joe Sutter left the 737 development program to design the 747. In April 1966, Pan Am ordered 25 Boeing 747-100 aircraft, and in late 1966, Pratt & Whitney agreed to develop the JT9D engine, a high-bypass turbofan. On September 30, 1968, the first 747 was rolled out of the custom-built Everett Plant, the world's largest building by volume. The 747's first flight took place on February 9, 1969, and the 747 was certified in December 1969. It entered service with Pan Am on January 22, 1970. The 747 was the first airplane called a "Jumbo Jet" as the first wide-body airliner.

The 747 is a four-engined jet aircraft, initially powered by Pratt & Whitney JT9D turbofan engines, then General Electric CF6 and Rolls-Royce RB211 engines for the original variants. With a ten-abreast economy seating, it typically accommodates 366 passengers in three travel classes. It has a pronounced 37.5° wing sweep, allowing a Mach 0.85 (490 kn; 900 km/h) cruise speed, and its heavy weight is supported by four main landing gear legs, each with a four-wheel bogie. The partial double-deck aircraft was designed with a raised cockpit so it could be converted to a freighter airplane by installing a front cargo door, as it was initially thought that it would eventually be superseded by supersonic transports.

Air-breathing jet engines typically feature a rotating air compressor powered by a turbine, with the leftover power providing thrust through the propelling nozzle—this process is known as the Brayton thermodynamic cycle. Jet aircraft use such engines for long-distance travel. Early jet aircraft used turbojet engines that were relatively inefficient for subsonic flight. Most modern subsonic jet aircraft use more complex high-bypass turbofan engines. They give higher speed and greater fuel efficiency than piston and propeller aeroengines over long distances. A few air-breathing engines made for high-speed applications (ramjets and scramjets) use the ram effect of the vehicle's speed instead of a mechanical compressor.

A trijet is a jet aircraft powered by three jet engines. In general, passenger airline trijets are considered to be second-generation jet airliners, due to their innovative engine locations, in addition to the advancement of turbofan technology. Trijets are more efficient than quadjets, but not as efficient as twinjets, which replaced trijets as larger and more reliable turbofan engines became available.

An airbreathing jet engine (or ducted jet engine) is a jet engine in which the exhaust gas which supplies jet propulsion is atmospheric air, which is taken in, compressed, heated, and expanded back to atmospheric pressure through a propelling nozzle. Compression may be provided by a gas turbine, as in the original turbojet and newer turbofan, or arise solely from the ram pressure of the vehicle's velocity, as with the ramjet and pulsejet.

All practical airbreathing jet engines heat the air by burning fuel. Alternatively a heat exchanger may be used, as in a nuclear-powered jet engine. Most modern jet engines are turbofans, which are more fuel efficient than turbojets because the thrust supplied by the gas turbine is augmented by bypass air passing through a ducted fan.

The Rolls-Royce Marine Spey is a marine gas turbine based on the Rolls-Royce Spey and TF41 aircraft turbofan engines. The Marine Spey currently powers seven ship classes including the Royal Navy's Type 23 frigates and provides a power output of 19.5 MW (about 26,150HP). The Marine Spey incorporates technology from the Tay and RB211.

A gas turbine engine, or, informally, a gas turbine, is a type of continuous flow internal combustion engine. The main parts common to all gas turbine engines form the power-producing part (known as the gas generator or core) and are, in the direction of flow:

• a rotating gas compressor
• a combustor
• a compressor-driving turbine.

Additional components have to be added to the gas generator to suit its application. Common to all is an air inlet but with different configurations to suit the requirements of marine use, land use or flight at speeds varying from stationary to supersonic. A propelling nozzle is added to produce thrust for flight. An extra turbine is added to drive a propeller (turboprop) or ducted fan (turbofan) to reduce fuel consumption (by increasing propulsive efficiency) at subsonic flight speeds. An extra turbine is also required to drive a helicopter rotor or land-vehicle transmission (turboshaft), marine propeller or electrical generator (power turbine). Greater thrust-to-weight ratio for flight is achieved with the addition of an afterburner.