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Speaker 1: Welcome to brain Stuff from how stuff works dot com,

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Speaker 1: where smart Happens high immercial Brain with today's question, how

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Speaker 1: does stealth technology work? The idea behind radar is simple.

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Speaker 1: It sends out a burst of radio energy, which is

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Speaker 1: then reflected back by any object that happens to encounter.

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Speaker 1: The radar antenna measures the time it takes for the

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Speaker 1: reflection to arrive, and with that information it can tell

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Speaker 1: how far away the object is. The metal body of

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Speaker 1: an airplane is a very good reflector for radar signals,

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Speaker 1: and this makes it easy to find and track airplanes

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Speaker 1: with radar equipment. The goal of stealth technology is to

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Speaker 1: make an airplane invisible to radar. There are two different

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Speaker 1: ways to create invisibility. The airplane could be shaped so

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Speaker 1: that any radar signals it reflects are reflected away from

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Speaker 1: the radar equipment, or the airplane could be covered in

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Speaker 1: materials that absorb radar signals. Most conventional aircraft have a

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Speaker 1: rounded shape. This shape makes them aerodynamic, but it also

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Speaker 1: creates a very efficient radar reflector. The round shape means

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Speaker 1: that no matter where the radar signal hits the plane,

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Speaker 1: some of the signal gets reflected back to the radar antenna.

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Speaker 1: A stealth aircraft, on the other hand, is made up

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Speaker 1: of completely flat surfaces and very sharp edges. When the

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Speaker 1: radar signal hits a stealth plane, the signal reflects at

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Speaker 1: an angle away from the radar antenna. In addition, surfaces

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Speaker 1: on stealth aircraft can be treated so they absorb rate

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Speaker 1: our energy as well. The overall result is that a

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Speaker 1: stealth aircraft can have a radar signature of a small

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Speaker 1: bird rather than an airplane. The only exception is when

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Speaker 1: the plane banks. There will often be a moment when

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Speaker 1: one of the panels of the plane will perfectly reflect

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Speaker 1: a burst of radar energy back to the radar antenna.

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Speaker 1: Do you have any ideas or suggestions for this podcast?

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Speaker 1: If so, please send me an email at podcast at

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Speaker 1: how stuff works dot com. For more on this and

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Speaker 1: thousands of other topics, go to how stuff works dot com. M. M.