The air pressure in a plane during flight is lower than at sea level.

VOA: special.2009.07.14

Atmospheric pressure was too great for the plane.

VOA: special.2010.07.07

"We know there's pressure to make that plane or you're traveling with family or bringing special foods you don't want to get squished, " said Fitzpatrick.

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Early ideas suggested blunting the nose of the plane to prevent the pressure waves joining up to form one intense shock wave, or lengthening the plane without increasing its weight to dampen the noise.

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Then, seemingly tired, she squints at the afternoon sun, hesitating before cracking her jaws in the yawning attitude of a passenger in a plane clearing her ears of accumulated air pressure.

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