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What is NASA doing about airplane noise?

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I hope they do something fast.

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Researchers in NASA's Quiet Aircraft Technology Program are working on active noise control.

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What's that?

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Let's find out.

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Sound is a wave. All waves have amplitude.

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The amplitude of a sound wave is its loudest.

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Think of a wave in a rope.

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The distance from the flat jump rope to the top of the wave is the amplitude.

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If you add two jump rope waves, one up and one down, the two waves cancel.

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Using one noise to cancel another noise is active noise control.

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Is all that noise from the engine?

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On takeoff, yes. But on landing, a nearly equal amount comes from the airframe.

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NASA is developing technologies to reduce noise inside the airplane and in airport communities.

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To learn more, visit our website.

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Until next time, I'm Grant with another cool NASA fact.

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NASA Jet Propulsion Laboratory, California Institute of Technology