Structural Secrecy in Irish Aviation Regulation: From Rescue 116 to the North Runway

The paper applies four established analytical frameworks (Vaughan's structural secrecy, Reason's defence-in-depth, Pierson's path-dependence, Power's audit society) to two Irish aviation-oversight cases: the 2017 loss of Rescue 116 off Black Rock, Co. Mayo, and the 2022-to-present deviation of Dublin Airport North Runway departure routes from the geometry assessed in the 2007 Environmental Impact Statement. The Air Accident Investigation Unit's 2021 report on Rescue 116 identified an expertise absence at the Department of Transport (Finding 51) and directed three recommendations to the Minister (IRLD2021029, 031, 032), all formally accepted November 2021. Freedom of Information responses (TRA-FOI-2025-0121, 30 June 2025; TRA-FOI-2026-0086, 9 April 2026) establish that four and a half years on the Department holds 49 generalist staff with no aviation qualifications framework, no periodic review has been conducted, and the relevant records do not exist. The same Department, oversight body for Dublin Airport, has produced no assessment of a departure-route geometry that deviates by up to 86 degrees from the EIS routing and newly directly overflies 4,008 buildings / 13,923 residents. The four-body chain (Department, IAA, AirNav, daa, with ANCA at the noise seam) distributes mandates such that each body may claim individual compliance while none is positioned to close the gap at the seam. The analysis shows that the 2017 accident and the 2026 unassessed geometry share a single structural signature: bodies that cannot see the holes in each other's defences, holes that align cumulatively, a configuration stable under external pressure, and procedural substitutes (reviews, consultancies, certifications) offered in place of substantive institutional change. No novel mechanism is advanced. The fix the analysis predicts will work is structural: create the missing instrument connecting procedure design to environmental assessment and acquire the competence to operate it, as the AAIU recommended in 2021.