Soundscape Assessment of Aircraft Height and Size

Area of Science:

• Acoustics and Psychoacoustics
• Environmental Psychology
• Transportation Noise Analysis

Background:

• Aircraft noise is often perceived more negatively than other transportation noise, even at equivalent sound pressure levels.
• The reasons for this negative perception, particularly the role of non-acoustical factors like visual cues, are not well understood.
• Existing soundscape assessments often overlook the multisensory aspects of environmental noise events.

Purpose of the Study:

• To develop and propose a novel method for assessing the visual impact of aircraft, specifically perceived aircraft height and size.
• To investigate how visual factors interact with acoustic indicators in community perception of aircraft noise.
• To explore the multisensory relationships influencing listener assessments of aircraft events.

Main Methods:

• Utilized a soundscape approach combining acoustical indicators (dB, L_A,max, background sound pressure level) with social surveys.
• Employed postal questionnaires for long-term exposure and field interviews for contextual perception.
• Developed new questions to capture multisensory relationships, including perceived visual height based on visual and aircraft size, reading and aircraft distance.

Main Results:

• Established a method to quantify perceived visual height of airplanes using visual and aircraft size, and reading and aircraft distance.
• Demonstrated that visual assessments complement and contextualize acoustic assessments of aircraft events.
• Showcased the flexibility of the method in comparing live viewing versus memory recall, examining acoustic memory and expectations.

Conclusions:

• Perceived aircraft height and size significantly influence the multisensory evaluation of aircraft noise events.
• The proposed method effectively integrates visual and acoustic data, highlighting the multisensory nature of perception.
• This approach offers a more comprehensive understanding of community responses to aircraft noise, moving beyond purely acoustic metrics.