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In aviation, a flameout (or flame-out) is the run-down of a jet engine or other turbine engine due to the extinction of the flame in its combustor. The loss of flame can have a variety of causes, such as fuel starvation, excessive altitude, compressor stall, foreign object damage deriving from birds, hail, or volcanic ash, severe precipitation, mechanical failure, or very low ambient temperatures. [1] [2]


Engine control

Early jet engines were prone to flameout following disturbances of inlet airflow, or sudden or inappropriate thrust lever movements, which resulted in incorrect air-fuel ratios in the combustion chamber. Modern engines are much more robust in this respect, and are often digitally controlled, which allows for a significantly more effective control of all engine parameters to prevent flameouts and even initiate an automatic restart if a flameout occurs.

Flameouts occur most frequently at intermediate or low power settings such as in cruise and descent. To prevent a flameout when atmospheric or operational conditions are conducive to it, engine control systems usually provide a continuous ignition function. Ignitors are normally used only at engine start, until the flame in the combustion chamber becomes self-sustaining. With continuous ignition, instead, the ignitors are continually sparked every second or less, so that if a flameout occurs, combustion can immediately be restored. [3]

Engine restart

Following a flameout, jet engines can normally be restarted in flight, provided the aircraft is flying within the portion of its flight envelope defined as the engine relight envelope. Depending on where in the relight envelope the restart is attempted (that is depending on the aircraft's airspeed and altitude), the procedure may simply rely on the airflow (windmill restart) or require the use of the starter (starter-assisted restart) in order for the compressor to achieve sufficient rotational speed for successful ignition. [4]

For example, the Airbus A320 passenger jet has a maximum ceiling of over 39,000 ft (12,000 m), but its certified engine relight envelope only extends to 30,000 ft (9,100 m). Up to that altitude, a windmill restart can be attempted at airspeeds greater than 260 knots (480 km/h; 300 mph); below that speed, a starter-assisted relight is required. [5]

Core lock can make restart impossible.

Related Research Articles

Ramjet Atmospheric jet engine designed to operate at supersonic speeds

A ramjet, or athodyd, is a form of airbreathing jet engine that uses the forward motion of the engine to produce thrust. Since it produces no thrust when stationary ramjet-powered vehicles require an assisted take-off like a rocket assist to accelerate it to a speed where it begins to produce thrust. Ramjets work most efficiently at supersonic speeds around Mach 3 and can operate up to speeds of Mach 6.

Turboprop Turbine engine driving an aircraft propeller

A turboprop engine is a turbine engine that drives an aircraft propeller.

Turbofan Airbreathing jet engine designed to provide thrust by driving a fan

The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the turbo portion refers to a gas turbine engine which achieves mechanical energy from combustion, and the fan, a ducted fan that uses the mechanical energy from the gas turbine to force air rearwards. Thus, whereas all the air taken in by a turbojet passes through the combustion chamber and turbines, in a turbofan some of that air bypasses these components. A turbofan thus can be thought of as a turbojet being used to drive a ducted fan, with both of these contributing to the thrust.

Aircraft engine controls

Aircraft engine controls provide a means for the pilot to control and monitor the operation of the aircraft's powerplant. This article describes controls used with a basic internal-combustion engine driving a propeller. Some optional or more advanced configurations are described at the end of the article. Jet turbine engines use different operating principles and have their own sets of controls and sensors.

CFM International CFM56 Turbofan aircraft engine

The CFM International CFM56 series is a French-American family of high-bypass turbofan aircraft engines made by CFM International (CFMI), with a thrust range of 18,500 to 34,000 lbf. CFMI is a 50–50 joint-owned company of Safran Aircraft Engines of France, and GE Aviation (GE) of the United States. Both companies are responsible for producing components and each has its own final assembly line. GE produces the high-pressure compressor, combustor, and high-pressure turbine, Safran manufactures the fan, gearbox, exhaust and the low-pressure turbine, and some components are made by Avio of Italy and Honeywell from the US. The engines are assembled by GE in Evendale, Ohio, and by Safran in Villaroche, France. The completed engines are marketed by CFMI. Despite initial export restrictions, it is the most used turbofan aircraft engine in the world, in four major variants.

Afterburner Adds additional thrust to an engine at the cost of increased fuel consumption

An afterburner is an additional combustion component used on some jet engines, mostly those on military supersonic aircraft. Its purpose is to increase thrust, usually for supersonic flight, takeoff, and combat. The afterburning process injects additional fuel into a combustor in the jet pipe behind the turbine, "reheating" the exhaust gas. Afterburning significantly increases thrust as an alternative to using a bigger engine with its attendant weight penalty, but at the cost of increased fuel consumption which limits its use to short periods. This aircraft application of reheat contrasts with the meaning and implementation of reheat applicable to gas turbines driving electrical generators and which reduces fuel consumption.

Pratt & Whitney J58 A high-speed jet engine

The Pratt & Whitney J58 was an American jet engine that powered the Lockheed A-12, and subsequently the YF-12 and the SR-71 aircraft. It was an afterburning turbojet engine with a unique compressor bleed to the afterburner that gave increased thrust at high speeds. Because of the wide speed range of the aircraft, the engine needed two modes of operation to take it from stationary on the ground to 2,000 mph (3,200 km/h) at altitude. It was a conventional afterburning turbojet for take-off and acceleration to Mach 2 and then used permanent compressor bleed to the afterburner above Mach 2. The way the engine worked at cruise led it to be described as "acting like a turboramjet". It has also been described as a turboramjet based on incorrect statements describing the turbomachinery as being completely bypassed.

A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, combustion chamber or flame holder. In a gas turbine engine, the combustor or combustion chamber is fed high-pressure air by the compression system. The combustor then heats this air at constant pressure as the fuel/air mix burns. As it burns the fuel/air mix heats and rapidly expands. The burned mix is exhausted from the combustor through the nozzle guide vanes to the turbine. In the case of a ramjet or scramjet engines, the exhaust is directly fed out through the nozzle.

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In aeronautics, an environmental control system (ECS) of an aircraft is an essential component which provides air supply, thermal control and cabin pressurization for the crew and passengers. Additional functions include the cooling of avionics, smoke detection, and fire suppression.

A compressor stall is a local disruption of the airflow in the compressor of a gas turbine or turbocharger. A stall that results in the complete disruption of the airflow through the compressor is referred to as a compressor surge. The severity of the phenomenon ranges from a momentary power drop barely registered by the engine instruments to a complete loss of compression in case of a surge, requiring adjustments in the fuel flow to recover normal operation.

Pinnacle Airlines Flight 3701 2004 aviation accident

On October 14, 2004, Pinnacle Airlines Flight 3701 crashed near Jefferson City, Missouri, United States, while flying from Little Rock National Airport in Little Rock, Arkansas, United States, to Minneapolis–Saint Paul International Airport in Minnesota, United States. Flight 3701 was a repositioning flight with no passengers aboard; both pilots were killed. Federal investigators determined the crash was due to the pilots' unprofessional behavior and disregard for training and procedures.

Air turborocket

The air turborocket is a form of combined-cycle jet engine. The basic layout includes a gas generator, which produces high pressure gas, that drives a turbine/compressor assembly which compresses atmospheric air into a combustion chamber. This mixture is then combusted before leaving the device through a nozzle and creating thrust.

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A powered aircraft is an aircraft that uses onboard propulsion with mechanical power generated by an aircraft engine of some kind.

Aircraft engine starting Overview article on aircraft engine starting methods

Many variations of aircraft engine starting have been used since the Wright brothers made their first powered flight in 1903. The methods used have been designed for weight saving, simplicity of operation and reliability. Early piston engines were started by hand, with geared hand starting, electrical and cartridge-operated systems for larger engines being developed between the wars.

Internal combustion engine Engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber

An internal combustion engine is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to. This replaced the external combustion engine for applications where the weight or size of an engine was more important.


  1. "Turbo Jet Flame Out by Ask a Scientist". Argone National Laboratory. 2003. Archived from the original on 28 February 2015. Retrieved 25 March 2012.
  2. Garrison, Peter (1 September 2006). "Flameout: Why the fire in a perfectly healthy jet engine can die". Air & Space Magazine. Retrieved 25 March 2012.
  3. "Airplane Turbofan Engine Operation and Malfunctions, Basic Familiarization for Flight Crews" (doc). FAA. Archived from the original on 4 September 2013. Retrieved 25 March 2012.
  4. "Gas Turbine Performance". 2nd edition. P.P.Walsh P. Fletcher. ISBN   0-632-06434-X p. 484
  5. A318/A319/A320/A321 Flight Crew Operating Manual. Airbus. 17 April 2017. p. PRO-ABN-ENG 13/106.