A new semantic differential for measuring the perceived quality of aircraft sounds

Abstract

A new semantic differential (SD) was developed in order to measure the quality of aircraft sounds. The SD consists of 10 items which have relation to the emitted noise of different engine components and the airframe. The items refer to technical components of an engine. The reliability of an evaluation of one sound falls below the minimum value of 0.70 if only one judge is involved. For most of the items average scores based on sample sizes up to 30 judges will satisfy the requirements concerning reliability. The item "safe" should not be considered when evaluating arrival and departure sounds because a reliable measurement presupposes a considerable greater sample size. For the same reason the item "powerful" should not be considered when arrival sounds need to be evaluated and the item "booming" should be disregarded when departure sounds need to be rated.