ContextIn February 2012, to achieve compliance with the statutory regulations on airspace design, NAV CANADA re-located an arrivals flight path for Toronto Pearson International Airport, known as the South Downwind. From a community perspective the airspace change was achieved without appropriate engagement or consultation. The impact of the re-location was to move noise over communities that previously had little or no disruption from aviation noise, creating large numbers of newly disturbed residents. No noise mitigations were implemented in the five years following the airspace change, whilst traffic volumes increased substantially, public frustrations and resentment festered and NAV CANADA were seen as unaccountable.
Role of Helios
In summer 2016 NAV CANADA appointed Helios to undertake an independent review of the Toronto airspace to assess what mitigations were possible. The only limitations on Helios were to maintain safety and safeguard projected traffic growth.
Helios developed an extensive online and face to face engagement initiative with communities, airlines, the airport operator (GTAA) and NAV CANADA. We spent time ensuring that we focused on how we were communicating and not just on what; tailoring our approach to the different stakeholder groups and their understanding of aviation and noise management. This allowed:
- Communities to inform the terms of reference for the review, share their experiences and aspirations, understand and comment on potential recommendations.
- Airlines to share their perspective on the efficiency of the airspace, experience of local ATC and provide suggestions for how the airspace and ATC operations could be improved to deliver less noise.
- Helios to elicit knowledge of the current operation from NAV CANADA and the GTAA as well as to test potential recommendations to understand any local constraints.
Another important aspect of the review was extensive analysis of previous flight operations, enabling Helios to test assertions made by communities. For example, we analysed both vertical and horizontal distribution of flights, to test if there had been noticeable changes in altitude or lateral concentration following the airspace change of 2012.
A key activity was to investigate potential mitigations such as reducing noise at source, better descent management, increased controller / pilot collaboration, low-power low-drag descents, reduced landing flaps, opportunities with performance based navigation, runway alternation schemes, changes to arrival procedures to enable flights to remain higher for longer, steeper glide paths, re-location of flight paths, alternative sequencing operations and time based operations.
Whilst the overall lateral and vertical dispersion had not changed. The analysis indicated that there was increased concentration within 150m either side of the flightpath centreline and marginal changes in altitude; delivering only a tiny, almost undetectable, change to the noise experienced at ground level.
The review produced a comprehensive set of conclusions and recommendations spanning the reduction of noise at source, noise abatement, operational restrictions and land-use planning. The outcome of the review and the reasoning behind our conclusions and recommendations was communicated to all stakeholders through a single presentation, that was simultaneously webcast, to over 600 people. Following the presentation a 181 page report was made publicly available both in hardcopy and online.
NAV CANADA took 60 days to consider the recommendations made by the review and announced that they will implement all bar two of the recommendations. Whilst NAV CANADA will not implement two of the recommendations they support the intention of the recommendations yet believe there is an alternative approach to reaching the same end.
For further information on this project please contact Nick Boud