Noise and Vibrations

What is the maximum permissible sound level of continuous unprotected exposure to steady-state noise for 8 hours as established by the Surgeon General?

85db

Which of the following is a true statement when referring to sound?

A) Produced by a pressure wave that causes a disturbance in surrounding air B) Density of the substance determines the speed at which the sound and pressure waves will travel C) Transmitted through any elastic medium

The maximum displacement of an object from its position at rest?

Amplitude

If the HGU-56 and IHADSS helmets are worn properly, the noise attenuation brings the noise exposure within the confines of the damage risk criteria for every aircraft except which two aircraft.

UH 60 & CH-47

The highest level of vibration occurs during the transition from hover to cruise fight and cruise to hover

hover to cruise fight and cruise to hover

The highest level of vibration occurs during the transition from flight to a hover and hover to flight

true