Acoustic camera hunts down aircraft cabin noise

Small noises can also develop over time, so testers need to hunt and eliminate them rigorously. Especially during expensive flight tests, noise source location must be fast.

The acoustic camera from Brüel & Kjær is a complete kit for real-time noise source identification and data recording that has been designed to be up and running in 20 seconds.

It makes it easy to identify and measure non-stationary noise events in areas such as aircraft cabins, cargo bays, and passenger vehicles.

The acoustic camera gives an instant sound map of the object that it is focused on. Mounted on the hand-held microphone array is a tablet that displays the sound map, laid over a real-time video of the target.

Colour-coded noise contours show the strength of the sound, from which the user can easily determine the sound’s source – from the brightest contours. Good maps allow reliable ranking of noise sources in order of importance. 

As the acoustic camera displays and analyses noise in real-time, it can also map moving objects, and users can walk and move around with it. Once they identify an area of interest, they can take a screenshot or video using the built-in optical camera, which helps to easily explain and refer to the measurements later on.

Recorded data can be exported for post processing, where transient sounds can be replayed and adjusted for frequency, to help analyse them in detail.