Measurements and Ratings of Aircraft Landing Noise
Time: Tue 2023-12-05 09.00
Subject area: Engineering Mechanics
Doctoral student: Anders Johansson , Lättkonstruktioner, marina system, flyg- och rymdteknik, rörelsemekanik
Opponent: Prof. Antonio Filippone,
Supervisor: Karl Bolin, Lättkonstruktioner, marina system, flyg- och rymdteknik, rörelsemekanik; Susann Boij, Lättkonstruktioner, marina system, flyg- och rymdteknik, rörelsemekanik
Following the liberalization of the aviation market in the mid-1990s, there has been a significant increase in aviation activities worldwide. This has inevitably resulted in the expansion of airports, which in numerous regions has led to concern and conflicts over increased noise levels. For people residing near airports, the constant noise can be distressing, interrupting sleep and leading to general noise annoyance. Indeed, noise pollution is serious and ranks second as the most significant environmental health hazard after air pollution. The World Health Organization's 2018 guidelines on environmental noise affirm this, highlighting the harmful effects and setting stricter aircraft noise thresholds than previous standards.This poses challenges, as the current technological landscape finds it difficult to achieve the necessary noise reduction. Plus, given the long life expectancy of the existing aircraft fleets, modern technological advancements pushing noise reduction will not be realized within the next decade. Noise mitigation strategies should, therefore, not only focus on technological advancements but also consider other paths forward, such as noise abatement landing procedures.
During the flight cycle, it is the landing phase that contributes most significantly to the noise impact. This is well-known, and through the years, methods have been designed that effectively mitigate noise during the middle stages of the approach, principally by maintaining aircraft at elevated altitudes for extended periods and bypassing noise-sensitive areas. However, the dynamic noise characteristics of the aircraft itself are often overlooked, missing opportunities for noise reduction in closer proximity to the airport. Adopting an experimental approach, the work presented in this thesis investigates the possibilities of quieter landing procedures, focusing on the final phase of the approach and the aircraft as a variable noise source. Findings suggest that quieter approach procedures are feasible without interfering with established safety standards, emphasizing delayed landing gear deployment as a key strategy. However, reconciling the goals of sustainable aviation with the demands of present-day air traffic remains a formidable challenge. In other words, fly less.