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Speaker 1: Welcome to Brainstuff from house stuff Works dot com where

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Speaker 1: smart happens. Hi Am Marshall Brain with today's question, how

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Speaker 1: does an afterburner work on a jet engine? A jet engine,

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Speaker 1: like a rocket engine, is a reaction engine. It works

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Speaker 1: by throwing mass in one direction and taking advantage of

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Speaker 1: the reaction in the opposite direction. In the case of

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Speaker 1: a jet engine, the engine bird's fuel like kerosene with

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Speaker 1: error from the atmosphere. The burning fuel heats and expands

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Speaker 1: the air, and this hot air shoots out the exhaust

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Speaker 1: end of the engine to create thrust. Most modern jet

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Speaker 1: engines use a turbine to improve the efficiency of the

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Speaker 1: engine and allow the engine to work at low speeds.

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Speaker 1: One part of the turbine sucks in airror and compresses

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Speaker 1: it before the fuel is injected. The back portion of

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Speaker 1: the turbine acts like a windmill, extracting entered from the

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Speaker 1: exhaust gases and using the energy to spin the compressor portion.

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Speaker 1: A modern turbine engine is extremely efficient and there's still

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Speaker 1: a lot of oxygen available in the exhaust stream. The

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Speaker 1: idea behind an afterburner is to inject fuel directly into

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Speaker 1: that exhaust stream and burn it using the remaining oxygen.

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Speaker 1: This heats and expands the exhaust gases further, and it

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Speaker 1: can increase the thrust of a jet engine by fifty

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Speaker 1: or more. The big advantage of an afterburner is that

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Speaker 1: you can significantly increase the thrust of the engine without

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Speaker 1: adding much weight or complexity to the engine. And afterburner

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Speaker 1: is nothing but a set of fuel injectors, a tube

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Speaker 1: and flame holder that the fuel burns in, and an

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Speaker 1: adjustable nozzle. A jet engine with an afterburner needs that

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Speaker 1: adjustable nozzle so that it can work with and without

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Speaker 1: the afterburners on the disadvantage of an afterburner is that

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Speaker 1: it uses a ton of fuel for the power it generates. Therefore,

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Speaker 1: most planes use afterburners sparingly. For example, a military jet

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Speaker 1: would use its afterburners when taking off from a short

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Speaker 1: runway on an aircraft carrier or during a high speed

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Speaker 1: maneuver in a dog fight. Do you have any ideas

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Speaker 1: or suggestions for this podcast? If so, please send me

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Speaker 1: an email at podcast at how stuff works dot com.

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Speaker 1: For more on this and thousands of other topics, go

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Speaker 1: to how stuff works dot com and be sure to

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Speaker 1: check out the brain stuff blog on the how stuff

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Speaker 1: works dot Com home page,