Runway alternation is an effective way to spread the impact of airport noise across local communities. Switching departures and landings from one runway to the other part way through the day helps ensure that the noise is shared across different communities each day. But because of our agreement with the local residents of Cranford, we are not currently able to offer full runway alternation when the airport is on easterly operations.
Heathrow wants to end the Cranford Agreement and the government has agreed. But before the change can take effect, we must add new taxiways to both runways.
What is the Cranford Agreement?
The Cranford Agreement was established in the 1950s. It prevented planes from taking off over the village of Cranford, which is at the eastern end of the northern runway. The Cranford Agreement only applies when Heathrow is on easterly operations.
Heathrow switches to easterly operations when the wind is blowing from the east – which it does about 30% of the time. Because planes must take off and land into the wind, when easterly operations are in effect, planes approach Heathrow over Windsor to the west, and take off towards London. So because of the Cranford Agreement, most flights arrive on the northern runway and take off from the southern runway.
The agreement favours residents of Cranford at the expense of other communities such as Windsor and southern parts of Hounslow. Ending the Cranford Agreement will allow Heathrow to apply full runway alternation regardless of the wind direction, which is fairer to local residents overall.
Ending the Cranford Agreement
Government policy supports the ending of the Cranford Agreement. In 2008, the Government consulted with local residents about the Cranford Agreement and after reviewing the results of the consultation, in 2009 they announced that the agreement should end. The Coalition Government affirmed their support for this in 2010. However, because Heathrow’s taxiway infrastructure has been developed in the context of the Cranford Agreement, alterations to it are necessary before the northern runway can be used for departures on easterly operations. This includes building new access taxiways which require planning approval from the London Borough of Hillingdon.
We submitted our planning application in May 2013 and this was rejected in March 2014. We appealed the decision and a planning enquiry took place in June 2015.
Government announcement - February 2017
On 2 February 2017 the Planning Inspector recommended that the appeal be allowed and planning permission granted.
We welcome the Government’s decision to allow Heathrow to introduce full runway alternation on easterly operations. We will now review the details of this decision and consider how best to deliver full easterly alternation in conjunction with the Government’s airspace management proposals for London and our proposals for expansion.
Impact on residents
For most local residents, ending the Cranford Agreement will mean less noise (for the 30% of the time we operate on easterlies), but for a minority it will mean more.
We have plans that will mitigate the increase in noise. These include building a 5-metre high acoustic noise barrier at Longford, and offering double-glazing to those residents most affected by the change.