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When an aircraft flies over, my big glass window vibrates, making a ticktack beating. Its frequency sounds low, less than 10 beats per second actually. I'm wondering about the mechanism of this phenomenon. I have vague memory of supersonic plane and infrasound stuff from high school class long before. Not sure about the correctness and whether it really applies here. BTW, the aircraft doesn't look supersonic. It's not certain. But I guess it's not crucial here.
Is it caused by infrasound produced by aircraft? And how? The resonance of the window is subject to infrasound, why can I hear it? My tentative guess is I mingled the fequency of the audible ticktack beating with some other concept. Please kindly shed light.

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  • $\begingroup$ Just my guess - there's no reason the noise can't go into frequencies below what you can hear (about 20 hz). Of course if it makes your windows hit their frames, those clicks will be at a higher frequency so you can hear them. Nothing strange about that. $\endgroup$ Nov 25, 2014 at 1:44

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I think this has to do with sync of the oscilation of the glass molecules and the air molecules.

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When the planes passes over your house the air molecules approach the frequency that the glass moleculs oscilate, thus making the amplitude of oscilation bigger. That is why the glass vibrates.

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