AoC number


Primary domain


Secondary domain



Aircraft noise and emissions concerns may become the most important strategic obstacles for future development of air transport. These concerns impact the system in many ways, including:
• changes in certification requirements for aircraft
• changing aircraft traffic management
• introduction of environmental levies or the market based approach of emissions trading
Particularly, noise pollution has been cited as a major issue for residents on flight paths, including a health risk. A 2013 study in the British Medical Journal revealed that those who lived near Heathrow were 10-20% more likely to be admitted to a hospital for heart disease or failure; a corresponding American study revealed that for every 10-decibel increase in noise, the risk went up by 3.5%. Residents have therefore demanded stronger regulations on noise pollution and more lenient flight paths, to the point of taking legal action.
Solutions for reducing noise and emissions include the idea of a “Global Night Curfew”, where flights could only operate under certain times of day, and a “high-speed rail” that could substitute for flights under 500 miles. However, many of these ideas are expensive and unfeasible to implement. Therefore, airlines have instead opted to reduce emissions and noise pollution through design, including via electric propulsion systems.

Potential hazard

  1. Runway use policies creating potential for runway incursion/excursion and/or wrong runway takeoffs/landing
  2. New take-off and landing profiles which may reduce safety margins
  3. Noise curfews result in pressures to compress departures and arrivals into time slots near the beginning and end of curfew hours.
  4. For instance, Continuous Descent Approach (CDA) is a low-noise approach procedure. Aviation safety experts raise important concerns with flying aircraft at reduced power at lower altitudes. The recovery rate for any kind of disturbance at lower altitudes is reduced significantly. At lower altitudes on less power, aircraft is more difficult to control due to air density. Bird strikes and engine stalls are much more likely at lower altitudes at reduced power and any last minute alterations could create result in loss of control.

Corroborating sources and comments

Continuous Descent Operation is an operation, enabled by airspace design, procedure design and ATC facilitation, in which an arriving aircraft

descends continuously to the greatest possible extent,

by employing minimum engine thrust, ideally in a low drag configuration, prior to the final approach fix”.

Following a year-long trial, new lowered approach speeds will be implemented permanently at Gothenburg’s Landvetter and City airports in southern Sweden. The average speed reduction achieved during the EcoDescend project test period corresponds to an extended flight-time of about 35 seconds, but resulted in reduced emissions and fuel savings for the airlines. EcoDescend project manager Patrik Bergviken, who is also an air traffic controller at Landvetter, said: “The project calculated that the approach speed reduction during the test period corresponded to a saving of 800 tonnes of carbon dioxide per year in the Gothenburg area, which also means around SEK2 million ($300,000) less in fuel costs for the airlines. These are large volumes for a change which is relatively simple to implement and which is also in demand by the airlines.” (Flight paths and air traffic over Palo Alto, California. The doom-and-gloom tone of the page shows the attitude residents have towards this uptick in air traffic.) (Related to the above; legal battles have ensued, but residents want even stronger regulations on noise pollution and more beneficial airways.) (A 2013 study in the British Medical Journal revealed that those who lived near Heathrow were 10-20% more likely to be admitted to the hospital for heart disease or failure; for every 10-decibel increase in noise, an American study commented, the risk went up by 3.5%.) (Proposed solutions for reducing airport noise. Of particular note is the idea of a “high-speed rail” option in lieu of 500-mile-or-less flights, as is the idea of a “Global Night Curfew”. Many of these options, however, are unrealistic to implement.) (Overarching initiatives on controlling aircraft noise, courtesy of ICAO.)

Last update