Requirements are identified with respect to instrumentation; acoustic and atmospheric environment; data acquisition, reduction and presentation, and such other information as is needed for reporting the results.
This document makes no provision for predicting APU or component noise from basic engine characteristics or design parameters, nor for measuring noise of more than one aircraft operating at the same time.
No attempt is made to suggest acceptable levels of noise or suitable subjective criteria for judging acceptability. ICAO Annex 16 Volume I Attachment C provides guidance on recommended maximum noise levels.
This Aerospace Recommended Practice (ARP) describes standard conditions and procedures for measuring, analyzing and reporting noise resulting from operation of on-board APUs and associated equipment of aircraft undergoing servicing.
