Introduction Many airline jet aircraft have high cockpit noise levels .
Noisy cockpits make communication between pilots difficult, increasing the potential for error.
Loud cockpits could prevent pilots from hearing warning or alert sounds. Aircraft could be lost because a pilot could not hear ATC, a fellow crewmember, or a warning sound from an aircraft system, sounds that could be masked by high cockpit noise levels. Pilots are at risk of hearing damage and loss due to noisy jet cockpits. Because of high ambient noise levels, pilots must turn radio volume levels up to hear ATC communications, further endangering their hearing. Air conditioning subsystems may be turned off by pilots seeking quieter cockpits, reducing passenger comfort.