Mechanisms of Sound Production
A moving aircraft including the jet engine or propeller causes compression and rarefaction of the air, producing motion of air molecules. This movement propagates through the air as pressure waves. If these pressure waves are strong enough and within the audible frequency spectrum, a sensation of hearing is produced. Different aircraft types have different noise levels and frequencies. The noise originates from three main sources:
- Aerodynamic noise
- Engine and other mechanical noise
- Noise from aircraft systems
Read more about this topic: Aircraft Noise
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