London Biggin Hill Airport Runway 03 Approach A9912 N02 DC. Noise Assessment Extended D Charles 1.0 INTRODUCTION

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1 Project: File Ref: London Biggin Hill Airport Runway 03 Approach Date: 6 January 2016 Subject: From: Noise Assessment Extended D Charles To: Name Company Will Curtis Peter Mirams Barry Hawkins London Biggin Hill Airport London Biggin Hill Airport Cyrrus Ltd 1.0 INTRODUCTION London Biggin Hill Airport (LBHA) are proposing to change the approach procedure for aircraft approaching Runway 03. In summary the existing procedure is to approach from the north of the airport, on the extended centreline of runway 21, until visual contact with the runway has been established. At this point, aircraft then break off to the west and loop around to approach Runway 03 from the south. The proposed option introduces a separate procedure that does not include a visual element, or an element of approaching from the north. Following the CAA Guidance on the Application of the Airspace Change Process (CAP725) an environmental assessment of the proposed change was conducted by Bickerdike Allen Partners (BAP) and reported in the BAP note (Ref: A9912 N01 DC) dated 13 th November In it consideration was given to daytime noise contours and sound exposure level (SEL) footprints. Given the relatively low level of activity and number of aircraft types operating from Biggin Hill Airport, the note followed standard guidance and so concentrated on providing noise information for locations under the arrival track close to the airport. As a result, locations under more distant parts of the proposed arrival track from the airport were not specifically considered. To provide further information, predictions have now been undertaken for locations at regular intervals along the length of both the existing and proposed tracks. To undertake these additional predictions at locations further from the airport the noise model has been updated, specifically the extent of terrain data it contains has been expanded. Previously the terrain data was limited to areas close to the airport, which while sufficient for the daytime contours, was not sufficient for the SEL footprints at 80 db(a) on the existing route. Consequently in the previous assessment, although the daytime contours took into account the local terrain, the SEL footprints only allowed for the airport height and assumed the surrounding land was at the same elevation. The previously reported SEL footprints have therefore been updated to allow for local terrain, see Section 2.0. Page 1 of 7

2 The predictions for locations more distant from the airport along the existing and proposed arrival tracks are given in Section SOUND EXPOSURE LEVEL (SEL) FOOTPRINTS As noted above updated SEL footprints allowing for local terrain have been produced. These have been produced for arrivals onto Runway 03 using the existing procedure, represented by a set of three tracks corresponding to the edges and the centre of the swathe formed by the existing arrival tracks, as well as for the proposed procedure based on flight along the centreline of the approach track. The SEL footprints have been produced at 80 and 90 db(a) and are for the INM aircraft types CNA560XL and LEAR35, which represent the loudest and the most common aircraft types forecast to arrive in the early morning period. The SEL footprints are shown on the following figures: Figure A Rev1 90 db(a) SEL Footprints on Existing Routes Figure A Rev1 90 db(a) SEL Footprints on Proposed Routes Figure A Rev1 80 db(a) SEL Footprints on Existing Routes Figure A Rev1 80 db(a) SEL Footprints on Proposed Routes Comparing the 90 db(a) SEL footprints on Figures A Rev1 and A Rev1 finds that with the proposed procedure there is a modest reduction in the size of the footprints which is due to a small increase in aircraft heights in the final kilometres before touchdown. Comparing the 80 db(a) SEL footprints on Figures A Rev1 and A Rev1 finds that those with the proposed procedure are much smaller. This reduction is due to the existing procedure having aircraft in level flight at 1,200 ft amsl for several kilometres before their final approach, during which time they are producing 80 db(a) SEL on the ground in places. With the proposed procedure aircraft remain at least at 2,000 ft amsl until they begin their final approach, thereby reducing very significantly the area exposed to 80 db(a) SEL. The SEL footprint areas and the populations they contain are given below in Table 1 and Table 2. The population data has been determined from a database provided by CACI Ltd. Page 2 of 7

3 Table 1: SEL Footprint Areas Footprint Area (km 2 ) Route 80 db(a) SEL 90 db(a) SEL Cessna CNA560XL Existing Routes (1) 13.3 / 10.5 / / 0.6 / 0.5 Proposed Routes LEAR35 Existing Routes (1) 5.3 / 4.7 / Proposed Routes (1) Values relate to routes along the western edge, the centre, and the eastern edge of the swathe formed by the existing arrival tracks. Table 2: SEL Footprint Populations Population in Thousands (1) Route 80 db(a) SEL 90 db(a) SEL Cessna CNA560XL Existing Routes (2) 10.5 / 6.6 / Proposed Routes LEAR35 Existing Routes (2) 3.0 / 2.1 / Proposed Routes (1) Rounded to the nearest 100 (2) Values relate to routes along the western edge, the centre, and the eastern edge of the swathe formed by the existing arrival tracks. 3.0 LOCATIONS FURTHER FROM THE AIRPORT To provide noise information for locations more distant from the airport predictions have been undertaken for locations at 1 km intervals along both the existing and proposed tracks, commencing at 1 km from the landing threshold and finishing where the tracks for the existing and proposed procedures join at hold location, see Figure A The predictions are of the maximum noise levels during a flyover for the INM aircraft types CNA560XL and LEAR35, which represent the loudest and the most common aircraft types forecast to arrive in the early morning period. The predicted noise levels are given in Tables 3 and 4. Page 3 of 7

4 Table 3: Predicted Noise Levels INM Aircraft Type CNA560XL Distance from Landing Threshold (km) Maximum Noise Level from INM Aircraft Type CNA560XL (db L Amax ) Existing Tracks Swathe Western Edge Centre Eastern Edge Proposed Track onwards 65 to to to to 61 Page 4 of 7

5 Table 4: Predicted Noise Levels INM Aircraft Type LEAR35 Distance from Landing Threshold (km) Maximum Noise Level from INM Aircraft Type LEAR35 (db L Amax ) Existing Tracks Swathe Western Edge Centre Eastern Edge Proposed Track to to to to 58 Page 5 of 7

6 The results in Tables 3 and 4 show that the predicted noise levels from the arriving aircraft generally reduce with increasing distance along the track to the airport. This reduction is initially relatively rapid but then slows until relatively consistent levels are reached due to the aircraft being in level flight leaving the variation in ground height as the remaining variable. For the INM aircraft type CNA560XL using the existing routes the reduction is from over 80 db L Amax for the points within the first 6 to 9 kilometres, depending on the route, to around 67 db L Amax for those furthest from the airport. With the proposed operational procedures the noise levels are less, firstly due to the greater angle of final approach, and also because of the greater height of the level flight segment. As a result it is only for the first three kilometre points that the predicted level is above 80 db L Amax and at the points furthest from the airport the level is around 60 db L Amax. For the INM aircraft type LEAR35 the predicted levels follow the same pattern but are around 3 db(a) lower. To put these noise levels into content a comparison can be made to the noise levels in Table 3.1 of the Airports Commission Discussion Paper 05: Aviation Noise dated July 2013, see below. This suggests that the highest noise levels from the aircraft will be comparable to levels experienced close to a busy road for locations close to the airport but will reduce to levels similar to conversational speech at the more distant locations. Page 6 of 7

7 4.0 SUMMARY The earlier noise assessment of the existing and proposed procedures for Runway 03 arrivals has been extended to consider noise levels for locations at regular intervals along both the existing and proposed tracks. This has involved the expansion of the terrain data contained in the noise model which has allowed the SEL footprints previously produced to be updated. This update has no effect on daytime contours so the earlier finding is unchanged. Specifically that due to the relatively small size of the daytime contours there is generally no difference between the existing and proposed tracks within them, and consequently no significant change to the future contour is expected from the introduction of the new procedure. The updating of the SEL footprints has some effect on their areas and the populations they contain but findings with regard to the proposed change in procedures remain as before. Specifically that comparing the SEL footprints, those at 90 db(a) show a modest reduction in size with the proposed procedure. However comparing at 80 db(a) finds those with the proposed procedure are much smaller, and contain much smaller populations. The reductions are due to the significantly greater height of aircraft following the new procedure for most of their approach. Noise levels have also been predicted for locations further along the current and proposed approach paths. This finds that the highest noise levels from the aircraft will be comparable to levels experienced close to a busy road for locations close to the airport but will reduce to levels similar to conversational speech at the more distant locations. Duncan Rogers David Charles Peter Henson for Bickerdike Allen Partners Associate Partner Page 7 of 7

8 This drawing contains Ordnance Survey data Crown Copyright and database right Legend Lear35 CNA560XL Existing Arrival Tracks Proposed Arrival Track REVISIONS 121 Salusbury Road, London, NW6 6RG T: F: Biggin Hill Airport Airspace Change 90 db(a) SEL Footprints On Current Runway 03 Arrival Routes DRAWN: DR CHECKED: DC DATE: 07/12/2015 SCALE: FIGURE No: A Rev1

9 This drawing contains Ordnance Survey data Crown Copyright and database right Legend Lear35 CNA560XL Existing Arrival Tracks Proposed Arrival Track REVISIONS 121 Salusbury Road, London, NW6 6RG T: F: Biggin Hill Airport Airspace Change 90 db(a) SEL Footprints On Proposed Runway 03 Arrival Routes DRAWN: DR CHECKED: DC DATE: 07/12/2015 SCALE: FIGURE No: A Rev1

10 This drawing contains Ordnance Survey data Crown Copyright and database right Legend Lear35 CNA560XL Existing Arrival Tracks Proposed Arrival Track REVISIONS 121 Salusbury Road, London, NW6 6RG T: F: Biggin Hill Airport Airspace Change 80 db(a) SEL Footprints On Current Runway 03 Arrival Routes DRAWN: DR CHECKED: DC DATE: 07/12/2015 SCALE: FIGURE No: A Rev1

11 This drawing contains Ordnance Survey data Crown Copyright and database right Legend Lear35 CNA560XL Existing Arrival Tracks Proposed Arrival Track REVISIONS 121 Salusbury Road, London, NW6 6RG T: F: Biggin Hill Airport Airspace Change 80 db(a) SEL Footprints On Proposed Runway 03 Arrival Routes DRAWN: DR CHECKED: DC DATE: 07/12/2015 SCALE: FIGURE No: A Rev1

12 (30 km) (25 km) This drawing contains Ordnance Survey data Crown Copyright and database right Arrival Tracks Existing Western Edge Existing Centre Existing Eastern Edge (25 km) (20 km) (30 km) Proposed (Distance along track) (30 km) (25 km) (20 km) (15 km) REVISIONS (30 km) (20 km) (15 km) (10 km) (25 km) (15 km) (10 km) (5 km) (5 km) (1 km) 121 Salusbury Road, London, NW6 6RG T: F: Biggin Hill Airport Airspace Change (20 km) (10 km) Runway 03 Arrival Routes Assessment Locations DRAWN: DR CHECKED: DC (15 km) (10 km) DATE: 04/01/2016 SCALE: FIGURE No: A