Aviation Noise Attitudes Survey

We were directed to conduct the study by the Department for Transport (DfT).

The study forms part of our responsibility to support departments across the UK Government and devolved administrations to take informed decisions on aviation noise policy. This remit includes the provision of transparent and reliable information and research on aviation noise in the UK.   

The study is being funded by the DfT.

We are managing the study and are responsible for making decisions about it. We established a steering group to support the study, with membership from the Department for Transport (DfT), the Department for Environment, Food & Rural Affairs (Defra) and the UK Health Security Agency (UKHSA).

The steering group provides expert advice to ensure that a robust and practical design is achieved for the project and so that the results can be held in a high level of confidence. The steering group is chaired by us and meets regularly to review progress on the study and support our decision-making throughout the lifecycle of the study.

We recognise that ANAS is highly anticipated and that communities who are affected by noise have a strong interest in the study and its findings.

We established a Communities Engagement Group involving representation from the Aviation Environment Federation (AEF), the UK Airport Consultative Committees (UKACCs) and Heathrow Airport’s Teddington Action Group. Meetings are held with the group to share information and invite input about the development of the study.

We also provide updates to communities through our regular programme of meetings with the AEF, UKACCs and various airport noise forums, as well as to the Airspace and Noise Engagement Group (ANEG) which is chaired by the Department for Transport.

We appreciate that the aviation industry has a keen interest in the study and its findings and have established an Industry Engagement Group with representation from Airports UK (previously the Airport Operators’ Association), Airlines UK, and Heathrow Airport, London City Airport and Manchester Airport Group (MAG).  Meetings are held with the group to share information and invite input about the development of the study.

We also provide updates to industry through our regular programme of meetings with these bodies on wider topics, as well as through airport noise forums and the Airspace and Noise Engagement Group (ANEG) which is chaired by the Department for Transport.

Our project team has also been engaging with airports featured in the study to ensure the study uses the most accurate and appropriate noise data.

We don’t have the resources internally to produce and undertake fieldwork for a survey of this scale. We therefore invited tenders for the work in autumn 2022 and appointed Ipsos UK as an independent supplier of survey development and delivery services in February 2023.

Ipsos UK assisted with the overall research design, including questionnaire design and sampling methodology. It managed the data collection, data processing and fieldwork logistics, working alongside third-party printing and mailing delivery suppliers throughout the fieldwork period. It was also responsible for data management and creating a data file output that was fit for analysis purposes agreed with us.

Ipsos UK took part in stakeholder meetings which considered methodological challenges and delivered project progress updates.  Ipsos UK did not make any decisions on the strategic direction of the survey.

We also commissioned noise contouring data from the CAA’s Environmental Research and Consultancy Department (ERCD) and other external consultants to provide noise exposure data around selected airports. The data was used to identify eligible postcodes to participate in the study prior to the fieldwork, and to confirm noise exposure by postcode after the fieldwork. These suppliers were selected because of their ongoing responsibilities to supply noise contouring data for the relevant airports.

ANAS is a social research survey, using a push-to-web (online) approach for data collection. The survey was designed based on there being  two waves of data collection.

The key design elements are as follows:

Data collection method

• Push-to-web (online), with postal option

Data collection periods

• September-November 2023 and March-May 2024

Targeted population

• Random selection of households around 10 UK airports, exposed to at least 45 decibels, over an average summer day (a standard noise metric known as L_Aeq,16h), of aviation noise

Response targets

• 3,000 responses per airport distributed evenly across 6 ‘noise bands’; 30,000 responses overall

Push-to-web surveys are increasingly popular for surveys where large scale data collection is required, including for the Census 2021. The push-to-web method of data collection became increasingly popular during the Covid 19 pandemic and has now become the preferred approach for government-funded research projects.

A push-to-web survey has a number of advantages compared to the face-to-face data collection used historically. It enables the collection of a substantially higher number of responses than a face-to-face survey for the same budget, and therefore provides greater analysis potential by airport and noise exposure band. Fieldwork progress is not dependent on interviewer availability meaning there are no geographical restrictions.

Participants could access the online questionnaire by visiting the URL or accessing a QR code on the survey letters. They were then taken to a landing page which asked them to enter the unique password on their survey letters to access the online questionnaire. Participants could also pause the online questionnaire at any time and then access it again to pick up from the last question they answered. It was possible for up to two adults per household to participate in the survey.

It was important not to exclude any respondents who were unable to complete the survey online. Two postal questionnaires were posted to non-responding addresses, with a pre-paid return envelope.

Participants were targeted randomly based on addresses which were estimated to be exposed to specific levels of aviation noise around ten UK airports.

Noise exposure was organised into six ‘noise bands’ of three decibels per band, with the lowest band at 45-48 dB L_Aeq,16h and the highest covering exposure at 60 dB L_Aeq,16h or above (dB LA_Aeq,16h is the standard metric representing noise on a typical summer day)

The study aimed to achieve 500 responses for each noise band at each airport, producing 3,000 responses for each airport and 30,000 overall. A further 1,000 responses were targeted at a specific noise exposure of 63 dB L_Aeq,16h (the standard metric representing noise on a typical summer day) and above from three airports which had enough population exposed. The aim was to boost the number of responses at the highest noise exposure levels to allow us to determine whether there were differences in attitudes with greater precision.

Fieldwork was conducted around ten UK airports:

• Birmingham
• East Midlands International
• Edinburgh
• Gatwick
• Glasgow
• Heathrow
• Leeds Bradford
• London City
• Luton
• Manchester

We selected the airports purposively in consultation with the steering group. The goal was to select ten airports which could be seen as covering a reasonable range of  aviation noise characteristics experienced by the UK population.

The first qualifying characteristic was the volume of commercial flights at each airport. Noting that aviation was still recovering from the pandemic at time of selection, with fewer flights still operating than in 2019, a minimum benchmark of at least 10,000 flights a year in 2022 was the starting point. The next criteria was that there was evidence of sufficient population exposed to noise to meet the sample design which required 500 responses per noise band at each airport.  The next consideration was to select airports from across the UK, to include a mixture of airports with and without night flights. Most airports have a mixture of urban and rural populations, so we aimed to reflect this, and to avoid distorting the study by only choosing urban, or only choosing rural populations to survey.

Due to the selection criteria outlined above, it was not possible to include airports in Wales or Northern Ireland. The two Belfast airports: (Belfast City and Belfast International) did not have sufficient population exposed at higher noise levels while Cardiff did not meet the threshold of enough flights per year.

In total, the questionnaire contained 63 questions within six distinct sections as follows:

1. The local area – including length of time living in the local area, satisfaction with the local area as a place to live, and aspects participants most like and dislike about their local area.
2. Aviation noise – including if participants are bothered, disturbed or annoyed by aviation noise (both within the last 12 months and last three months); when participants are bothered, disturbed or annoyed by aviation noise; if aviation noise interferes with their sleep patterns and quality of life when at home; and whether participants think organisations including government, airports and airlines are doing anything to reduce noise from aeroplanes.
3. Sources of noise from road traffic and neighbours – whether participants are bothered, disturbed or annoyed from road traffic noise and/or from neighbours.
4. Health and wellbeing – including questions about participant’s health in general, mental health and wellbeing, and sensitivity to noise in general.
5. Homes and housing – questions about housing tenure, length of residence in current home, type of home and whether participants have access to an outdoor space such as a garden, terrace or balcony, type of windows (e.g. single or double-glazed), and reasons why participants close their windows or keep them closed, including for safety, security, warmth and noise reasons.
6. Demographics – standard background questions on household composition, including gender, age, ethnicity and working status of survey participants. Key demographics are important for the analysis of survey findings and so that an assessment can be made of how representative the achieved sample is of the population being surveyed.

It was anticipated the questionnaire would take 20 minutes to complete on average.

The questionnaire was designed in collaboration with the steering group, and taking into account feedback from industry and community groups’ representatives and from the CAA’s Environmental Sustainability Panel.  The questionnaire was also designed with reference to other national and international studies, including the Survey of Noise Attitudes (SoNA)  carried out in 2014, and the survey used in the first part of the Aviation Night Noise Effects (ANNE) study carried out in 2022.

Standardised questions covering noise annoyance were taken from the International Standard ISO 15666:2021 - Acoustics - Assessment of noise annoyance by means of social and socio-acoustic surveys.  ISO 15666 provides specifications for socio-acoustic surveys and social surveys which include questions on noise effects. It includes questions to be asked, response scales, and advice on key aspects of conducting the survey and reporting the results.

The questionnaire was designed and developed throughout the spring and summer of 2023, including a cognitive testing phase, before the final questions were agreed and signed off.

The study has been designed with two phases of fieldwork, with data gathering exercises taking place in autumn 2023 (September to November) and spring 2024 (March to May)

We selected this design to investigate the potential impact of seasonality on noise attitudes. It also allowed us to mitigate a potential risk of the entire set of results being impacted by any unusual external events taking place during either wave of fieldwork.

Findings from the study will be released at the earliest opportunity and our priority will be to ensure that any outputs are robust, reliable and accurate before release. Consequently, no results will be shared until the survey responses have been analysed against the noise dose calculated for the relevant time periods and the specific results being shared have been peer reviewed in order to meet the required quality standards for publication.

The lead priority will be the release of findings concerning the relationship between noise exposure and the percentage of the population highly annoyed i.e. ERR’s. The questionnaire invited various responses to the ISO/TS 15666:2021 question:

“thinking about [time period] when you are here at home, how much does noise from aeroplanes bother, disturb or annoy you?”

This question was asked to all participants with reference to “the last three months or so” and “the last 12 months or so” and with answer options using both the numerical rating scale from 0 (not at all) to 10 (extremely) and the verbal rating scale with options “not at all/slightly/moderately/very/extremely”.

The first outputs will be an overall assessment combining the data from both waves at a national level alongside the same analysis conducted separately for each wave.

This approach enables the supply of a comprehensive and robust set of information giving stakeholders the ability to draw more informed conclusions from a) a larger sample size and b) a holistic overview of the evidence based on data from both waves, including (for the first time in the UK) information on the potential effect of seasonality.