HC Deb 03 February 1988 vol 126 cc667-8W
Mr. Macdonald

To ask the Secretary of State for Defence if the calculation of the current noise contour maps around RAF Stornoway took into account run-and-break manoeuvres by incoming aircraft.

Mr. Freeman

No. However, run-and-break manoeuvres will be taken into account in the forthcoming noise survey at RAF Stornoway if this is practicable.

Mr. Macdonald

To ask the Secretary of State for Defence if the calculation of the current noise contour maps around RAF Stornoway took into account the noise of aircraft on the ground.

Mr. Freeman

Yes. The current noise contours for RAF Stornoway take into account all noise from aircraft operations, including noise emitted by aircraft prior to take-off and after landing. Noise from ground engine running is not included, but the forthcoming noise survey will take this into account if practicable.

Mr. Macdonald

To ask the Secretary of State for Defence what modifications to the Airnoise I aircraft noise model were made in mapping the noise contours around RAF Stornoway.

Mr. Freeman

Two major modifications have been made to the original Airnoise I computer model which formed the basis of the predicted noise contour used for the 1981 public inquiry at Stornoway. The current contour based on the Airnoise II model incorporates a bend to the north-east of the airfield reflecting the fact that militry aircraft taking-off fly over the sea in order to avoid the villages of Tong and Coll. The current contour is also slightly narrower because more reliable source data, derived from actual measurements of the RAF Phantom and Tornado aircraft, and more sophisticated computation methods, incorporating allowances for sound transmission through the atmosphere and close to the ground surface, have been used. These modifications are in line with internationally agreed criteria.