We appreciate that noise created at night can cause greater disturbance to people. It is generally quieter at night and the majority of people are trying to sleep. Also, night noise may seem worse in the summer when people are more likely to sleep with windows open.
There is no formal ban on night flights at Heathrow but since the 1960s, the Government has placed restrictions on them. Heathrow has some of the strictest restrictions of any hub airport in Europe in terms of movements permitted between 11:30pm and 6:00am. Heathrow is restricted to 5,800 take-offs and landings a year during these times.
Around 80% of the night flights at Heathrow are between 4:30am and 6:00am, with on average around 16 aircraft scheduled to arrive each day between these hours. Heathrow also has a voluntary ban in place that prevents flights from landing before 4:30am. There is also a night quota limit, which caps the amount of noise the airport can make at night.
Night flights are an important part of operations at airports around the world. The time differences in an inter-connected global transport system mean that it is difficult to avoid flights at night and early in the morning. An early morning arrival means a full day’s business can take place for some passengers while others may transfer onto a connecting flight at Heathrow.
Transfer passengers play an important role in maintaining the range and frequency of destinations served by Heathrow by feeding other flights. Independent studies have shown that night flights make a significant contribution to the UK economy.
Restrictions on night flights have been in place at Heathrow since 1962 and the structure of the current night flying restrictions at Heathrow has been in place since October 2017. The night flight restrictions are part of the Government defined noise measures under the Civil Aviation Act 1982.
Overview of restrictions:
At Heathrow we do not have any scheduled departures between 10:50pm and 6:00am or scheduled arrivals between 11:05pm and 4:45am. This means that there are no scheduled flights after 11:05pm and before 4:45am.
Heathrow also has an arrangement with its airlines that any planes scheduled to arrive from 4:45am will not land on the runway before 4:30am.
Over 90% of all the scheduled movements that operate during the night quota period are early morning arrivals and the majority of these are scheduled to arrive after 5am.
In addition, Heathrow does not have any scheduled freight flights in the night quota period (11:30pm to 6am).
Sometimes planes need to operate in the night period when they have not been scheduled to do so. This could be for a number of reasons such as delays that have built up during the day or for a technical fault with an aircraft that needs to be repaired.
There is always a delicate balance to be struck as to whether a flight should be allowed at night, considering the effects on local communities, passengers and the airline network.
Today we use a mixture of quota count and movement limits to control unscheduled nights flights.
The quota count system has been in place at Heathrow since 1993 and applies to all the major London airports.
Each plane has a number of points based on how noisy it is; the noisier the plane – the higher the number of points. If a plane lands or takes off during the night quota period (11:30pm-6am), its points count towards a limit based on whether it’s operating during the summer or winter period.
The night quota count system is designed to discourage the use of noisier older planes and encourage the use of quieter newer planes. No plane with a very high score (the oldest and noisiest) is allowed to take off or land during the night quota period.
There is also a movement limit which restricts the total number of flights that can take place in the night quota period over each summer and winter period.
The movement limit and quota count restrictions work together to make sure the overall number of night flights are limited and that the quietest planes are used:
The quota count combined with the movement limit ensure the total number of night flights are restricted at Heathrow and the use of the quietest planes is encouraged.
We aim to comply with the night noise restrictions in place, and report regularly to the Government and the Heathrow Community Engagement Board (HCEB).
However, there are occasions when a scheduled departure is unavoidably delayed because of operational or technical problems. If a flight needs to leave after 11:30pm for these reasons, the airline must request permission and explain the reason for the delay.
Where weather conditions – such as a heavy snowfall – cause widespread disruption, the government can give dispensation for additional night flights. These are in exceptional circumstances only, such as emergencies, delays which are likely to lead to serious congestion at the airport or serious hardship or suffering to passengers which result in prolonged disruption of air traffic.