Aviation noise is caused when aircraft taxi, fly, take-off and land. All aircraft produce some noise, however loud or quiet they are. The noise varies between aircraft types and even between aircraft of the same model. How this noise is received (by a person or microphone) at ground level will also vary. The noise from aircraft can be affected by many different factors, including temperature, humidity, engine size, loaded weight and wind speed. Time of day/night, background noise, duration and location are also important .
Most noise comes from the engines with the rest coming from the body of the aircraft - the airframe. Jet engines are less efficient at low altitude and in warm weather. When heavily loaded aircraft take off, especially in the spring and summer, the engines have to work extra hard for the aircraft to gain height. Airlines and holiday operators want aircraft to be as full as possible as often as possible - it's how they make their money
Noise is a type of pollution which creates annoyance and health issues. Research is increasingly finding that aviation noise can lead to both stress (day and night) and sleep disturbance, both of which can have negative impacts on health. Measuring aviation noise is critical to understanding who is exposed and what the potential impact on the communities may be.
Aircraft noise is not a statutory nuisance in the UK and it is specifically excluded from the Environment Act.