Aviation and Noise
One of the tools it provides is a kit allowing local government entities to determine the noise compatibility of a proposed airport. Organizations interested in airport noise can also access the information.Aviation noise can come from multiple sources both in the ground and in the air, and it doesnò€™t affect only the residents near an airport. Pilotsò€™ exposure to the noise of flight became an issue with the introduction of flight by the Wright Brothers. Noise is, of course, a product of the aircraft equipment: powerplants, transmission systems, jet efflux, propellers, rotors, hydraulic and electrical systems, communications systems and so on.
Besides the obvious mechanical noise, other noise is caused by the aerodynamic interaction between the ambient air layer and the surface of the aircraft. While these sounds allow a pilot to know immediately if his engine is functioning well, they can also create so much noise that inhabitants of the cockpit have to raise their voices to be heard. This level of sound is dangerous to communication and dangerous to the crewò€™s sense of hearing.
During takeoff, planes can produce noises higher than 100 decibels at ground level. With airports in the city, these planes may be flying close to homes, therefore creating sounds even louder than 100 decibels, a level loud enough to make conversation difficult.
Two broadly defined types of airframe noise are: Bluff Body Noise and Edge Noise. Mechanical noise comes mostly from the jet engines during takeoff and climb to altitude. However, during landing, the airframe is typically noisier. During takeoff, the jet noise is joined by fan noise from the engines. Because of the way the noise is formed, even a minor reduction in the exhaust velocity can result in lower fan noises.
Although annoyance is the primary factor of concern regarding aviation noise, loss of hearing has become another significant concern. Recent studies have shown the noise to be linked to other diseases as well. Whatò€™s more, noise can cause fatigue and irritability, as well as a decrease in performance. Noise becomes a distraction, and when noises, or distractions, are going on in peoplesò€™ brains, it is impossible for them to concentrate and be effective. Other subjective effects of aviations noise are: startle responses, loss of appetite, headache, vertigo, nausea and impaired concentration.
While some have questioned the veracity of the link between aviation noise exposure and hearing loss, studies have shown and verifiable connection. Any sounds louder than those in a normal conversation can damage the cochlea and the fine hairs in the cochlea that convert the sound waves into auditory nerve signals.