Air Borne Noise


Sound is caused by vibrations which transmit through a medium and reach the ear or some other form of detecting device. Sound is measured either as sound pressure/power levels either at various frequencies.
Airborne sound (or airborne noise) is the sound that is transmitted through the air.

Typically, airborne sound might be generated by:
  • Internal combusion or reciprocating machinery
  • Air moving equipments such as fans and ducts.
  • Propellers and Wind Turbines.

VES has extensive expertise in the measurement, mathematical modelling and engineering noise control of machinery noise, propulsion noise and flow-induced noises. We also advise on the prediction and control of noise and vibration in marine, aerospace & automobiles including interior trim design.

We helped several companies prepare the testing procedures and Quality Assurance plans to meet the rigorous MIL-STDs as well other international specifications like ISO/IEC. We also assisted several navies in drafting custom standards for machinery as well as propulsion noises. We carry out speech intelligibility testing of PA systems in aeroplanes and helicopters.

We have measured and assessed crew noise exposures in civil aircraft in light aircraft used for pilot training, and in helicopters used by police air support units. Crew noise exposures are the result not only of ambient noise in the cockpit, but also the noise of speech from the intercom and radio heard through headsets or flying helmets, with or without active noise reduction.

Other projects undertaken by VES include the design/prediction of acoustics for bullard tugs, frigates, submarines, VIP aircrafts and a number of unusual applied research projects on the general topic of internal noise and communications.