Quantifying single-event aircraft noise: a calibrated LAmax model for Dublin Airport North Runway departures

Public debate about Dublin Airport's North Runway (28R) departure noise is conducted almost entirely in long-term average metrics (Lden, Lnight), which conceal what residents actually experience: the peak level of each individual overflight. This paper builds a per-aircraft-type single-event LAmax model for 28R departures, calibrated directly on the airport operator's own noise-monitor data. Using 364,831 correlated noise-monitor events released by daa under access-to-information request AIE 2611 (1 March 2025 to 28 February 2026), we fit a per-type propagation law that reproduces the measured peak levels to about 2 dB RMS across the full 300 m to 2,600 m range the monitor network samples, and which cross-validates when fitted near the runway and tested on the farther events it never saw. We then render single-event LAmax footprints for the common fleet on the two flown departure arms, validated against the operator's own monitor medians, and contrast them with counterfactual footprints flown along the routes assessed in the 2004/2005 Environmental Impact Statement. The single-event levels are stark: at Kilcoskan National School the operator's own monitor records a median peak of 74.6 dBA, with 92% of events above 70 dBA and 167 events per day, against the roughly 50 to 53 dBA Lden figure commonly cited in public discussion. The school is directly under the flown northern departures yet about 2.5 km from the nearest route the Environmental Impact Statement assessed.