HC Deb 05 February 2001 vol 362 cc381-2W
Mr. Gerrard

To ask the Secretary of State for the Environment, Transport and the Regions what change has occurred in the last three years in the number of aircraft on flight paths above Walthamstow. [148500]

Mr. Robert Ainsworth

The number of aircraft that overfly Walthamstow and adjoining areas depends on the direction of operations at Heathrow which itself is dependent on wind direction and strength and so can vary from day to day. Due to the prevailing westerly winds, on average Heathrow operates in a westerly direction about 77 per cent. of the time, but this can vary considerably from year to year. The proportion of westerly operations at Heathrow in each of the last three years for which data are available was 1997–74 per cent., 1998–89 per cent, and 1999–66 per cent. As during any period of westerly operations approximately 50 per cent, of arriving aircraft approach Heathrow by overflying north London, it is possible (after adjusting for the proportion of westerly operations in each of the last three years) to give a rough estimate of the numbers of aircraft (including traffic using London City airport) that overflew Walthamstow or adjoining areas the estimates are 1997–89,000, 1999–107,000 and 1999–84,000.

Mr. Gerrard

To ask the Secretary of State for the Environment, Transport and the Regions what changes in flight paths into Heathrow have taken place within the last three years which have affected flight paths above Walthamstow. [148499]

Mr. Robert Ainsworth

None. Walthamstow along with adjoining parts of north London is situated beneath the radar manoeuvring area used during westerly operations for the tactical integration of arriving traffic descending from holding positions (stacks) located in the vicinity of Lambourne (Essex) and Bovingdon (Bucks). There are no fixed routes for arriving aircraft during this phase of their approach to Heathrow Airport, but they tend to follow a regular pattern that has not changed in any significant respect for many years. Departures from Heathrow during easterly operations may overfly the area once above an altitude of 4,000 ft. Traffic using London City Airport also overflies the area.