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BIGGIN HILL AIRPORT CONSULTATIVE COMMITTEE

Chairman: Mr J. Bowden

Clarkson Wright & Jakes Valiant House, 12 Knoll Rise Orpington, Kent, BR6 0PG

e-mail: john.bowden@cwj.co.uk

ANNUAL REPORT 2017

1. Summary

1.01 Under Section 35 of the Civil Aviation Act 1982 (as amended), the Biggin Hill Airport Consultative Committee is constituted from representatives of users of the Airport, local authorities and residents’ associations. 1.02 The aims of the Committee are:-

(a) to consult with and inform the local community of developments and plans for the Airport;

(b) to allow the efficient functioning and economic development of the Airport, its airport business community, its resident workforce, while moderating its impact upon local communities and the environment;

(c) to ensure that the Airport plays an active role in supporting the economic activities and objectives of the local and regional communities (business and residential).

1.03 The Committee meets four times a year in January (when the Annual General Meeting is also held), April, July and October. 1.04 All meetings were held at the Airport and, as usual, were well attended. 2. Membership

2.01 There were a number of changes that took place during the year namely that:

o Rob Shirley who had represented commercial users resigned because he was no longer working at the Airport. He has not yet been replaced;

o Vic Endacott due to business commitments was unable to attend all of the Committee’s meetings and the Reverend John Musson now represents Bromley Residents Federation and Cudham Residents Association. Vic Endacott now deputises when necessary and able;

o Councillor Richard Parry, the Chairman of the Noise and Safety Sub-Committee stood down as a member of Kent County Council. He does an excellent job as Chairman of the Sub-Committee and I was pleased when the Committee agreed that he would be appointed as an ex-officio member of the Committee in order that he could continue to serve in that role. A

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replacement representative of Kent County Council is in the process of being appointed to the Committee;

o Councillor Mark Watson was appointed to represent Croydon Council in place of Councillor Toni Letts who was unable to continue as a member of the Committee because she is now the Mayor of Croydon Borough;

o Councillor Martin Allen had been appointed as the representative of Tandridge District Council with Councillor Keith Jecks, the previous representative, as his substitute;

o Councillor Cameron McIntosh was appointed to represent Surrey County Council in place of Councillor David Hodge. Councillor Hodge stood down as he has been unable to attend many meetings since he became the Leader of Surrey County Council.

2.02 As suggested above, substitute members are permitted and a number attended in place of appointed members who were unable to attend meetings during the year.

3. Complaints and movements 3.01 I have already mentioned the Noise and Safety Sub-Committee in this report. It meets prior to meetings of the Committee and Richard Parry provides very full and clear reports of the results of its discussions of complaints at our meetings. 3.02 Of the complaints that are received regarding Biggin Hill movements, there were 194 that related to Biggin Hill movements during the year from 1 October 2016 to 30 September 2017. This is over twice as many as in the previous year and which I referred to in the last Annual Report. There were only 23 in the first half of the year and the increase appears to have a lot to do with the ease with which members of the public are now able to raise issues about aircraft movements using the new Noise Monitoring and Track Keeping System which became operational in April 2017. There is a local pressure group, Flightpath Watch, that is opposed to any expansion of the Airport and which encourages its members to use the system. Currently, all complaints are being investigated and responded to. 3.03 The new system allows the Sub-Committee to have accurate information about whether pilots contravene the Airport’s regulations and, of these 194 complaints, 44 of the movements involved contraventions. 3.04 In the year up to the end of September 2017 there were a total of 50,430 aircraft movements at the Airport. Therefore, the number of genuine complaints continues to be extremely low relative to the number of movements. 3.05 The Committee is provided with a map at each meeting showing from where complaints emanate to enable members to identify whether there are any consistent patterns of which it should be aware. It also enables members to ask for information about any complaints in areas that they represent or in which they live. 3.06 At the July meeting we received a paper setting out the Airport’s policy on processing noise complaints which is now posted on the Airport’s website. Increasingly, sanctions are being used against pilots who do not comply with the Airport’s regulations including being banned from using the Airport.

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3.07 Starting from the July meeting we have been receiving reports by Bickerdike Allen Partners LLP which provides noise contours for the operations at the Airport following the changes to the operating hours. 3.08 Richard Parry consistently reports that the complaints have been handled fairly and well by the Airport Managing Director. 4. 19 January 2017 meeting 4.01 The first meeting of the calendar year is always preceded by the Annual General Meeting at which the Annual Report is received. The most notable issues dealt with at the business meeting are referred to below. 4.02 Northolt Airport - I mentioned in the previous Annual Report that, at the request of the Committee, I had sent a letter to the Prime Minister and also to Liam Fox, MP and Michael Fallon MP about the unsuitability of Northolt Airport for the use of business aviation. I advised the Committee that I had not received a reply to that letter. The subject of Northolt airport came up at each meeting during 2017 and, regrettably, at the time of writing this report, I have still not received a reply. 4.03 We learnt at this meeting that RAF Northolt was preparing to spend an estimated £45m on installing arrestor beds and resurfacing the entire runway. It was suggested that these improvements were intended to obviate some of the safety shortfalls that have been highlighted. 4.04 Noise and Track Keeping System – the newly-installed system had undergone extensive testing and evaluation and a problem that had been identified was to be resolved imminently. The consultants for Bromley Council would then be checking that the limits on noise contours were being complied with. The Committee was informed that the system would be well publicised and a guide for the public on how to make use of it would be published. 4.03 Proposal for the new runway 03 Instrument Approach Procedure - members heard that the implementation of the revised runway 03 GPS approach could be delayed until late in the third quarter of 2017. At the October meeting we heard that it was probable that the revised procedure would not be introduced before March 2018 4.04 Runway 29/11 - we heard that, following a consultation with airport users, the decision had been taken to close the little-used runway 29/11. Whilst the light aircraft community was opposed to closure, business aviation had been in favour. 4.05 Proposed airport hotel - previous annual reports had referred to this proposal and the Committee was informed that finance had been obtained to fund its construction, subject to contract. It was hoped that construction would begin in late 2017. 4.06 College Update - previous Annual Reports had also referred to the proposed Aviation College and the Committee was informed that it was intended that it would have a workshop/hangar and ancillary accommodation. 5. 20 April 2017 meeting 5.01 This meeting covered many of the issues discussed at the previous meeting but included discussions on two Government consultation documents (paragraph 5.05 below).

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5.02 RAF Northolt - we heard that expert analysis of the RAF Northolt obstacle environment had been commissioned to identify the exact areas where it does not comply with civil safety standards. The Committee noted that the only practical way to mitigate the obstacles would be to shorten the runways. 5.03 New runway 03 GPS approach - the Committee received a report setting out the proposal that had been submitted to the Civil Aviation Authority for approval. 5.04 Noise and Track Keeping System - this was the item but took up the most time at this meeting and the Committee received a very interesting presentation on how to use the new system which was now fully operational. Members were pleased to learn that complaints and comments could still be made by telephone, letter, email, etc. and that any raised by such methods would be entered into the system. It is still the case that not everyone has access to or is able to use a computer. 5.05 Government Consultation – National Policy Statement and UK Airspace Strategy - we received a briefing paper on the following Government documents:

o Draft Airports National Policy Statement: New Runway Capacity and Infrastructure at Airports in the South-east of England and

o Upgrading UK Airspace - Strategic Rationale. 6. 27 July 2017 meeting

6.01 This was the longest meeting of the year when the main discussions arose from the increased activity at the Airport and environmental issues. 6.02 Variation of Airport operating hours - in earlier Annual Reports there have been references to the Airport’s application to extend its operating hours. The revised hours finally came into force on 1 May 2017 and the Committee learnt that, as anticipated, had resulted in business aviation operations on the Airport being boosted. 6.03 Tenants and businesses at Biggin Hill - I referred in the last Annual Report to Bombardier becoming a tenant at the Airport and members were advised that it was now operational with approximately 80 staff engaged. Further staff recruitment was taking place and at our October meeting the Airport Managing Director reported that the company was fully operational and had employed 100 staff and was continuing to recruit staff. 6.04 Business aviation continued to be displaced from major hub airports and the Committee heard that Airports such as Biggin Hill were being expected by Government to take the surplus business aviation activity. This would inevitably displace light aviation. One flight training company had already moved its circuit training operations elsewhere. In June it had had been decided to limit the number of training circuits that take place at the Airport on safety grounds. 6.05 Technical Training College - the Committee learnt that London South East Colleges had submitted a bid for £9m to build a dedicated campus for aerospace and technology skills at Biggin Hill London Aerospace & Technology College (LATC). Ahead of the building of the campus, which was expected to take place in 2019, London South East Colleges was launching 30 placements in Level 2 Diploma courses in Aerospace and Aviation Engineering to be run by City and Guilds and which started in September. 6.06 Environment - the new Noise Action Plan was mentioned in the 2016 Annual Report and it was noted that it was being used to improve the behaviour of pilots of

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aircraft using the Airport and contained some of the most stringent noise controls of any UK airport. A number of initiatives were being used to control noise as activity grows. Biggin Hill Airport had more controls and was quieter than any other commercial airport in the UK. Ground noise was now controlled by measures set out in the Ground Noise Action Plan to contain aircraft ground noise within the Airport boundary. Air quality monitoring activity around the boundary of the Airport had found air quality to be good. 6.07 Noise contours - as mentioned in paragraph 3.06 above, this was the first meeting at which the Committee received a paper that advised that Bickerdike Allen Partners LLP which set out noise contours for the operations at the Airport following the changes to the operating hours. They showed that noise emanating from all movements were well within the limits set. 7. 19 October 2017 meeting 7.01 This was a less substantial meeting than the July one. The discussions included the following. 7.02 Quasi-public transport operations - we heard that new European Aviation Safety Agency regulations had permitted private pilots to advertise their services on websites such as SkyUber and Wingly and to invite members of the public to share the cost of their flight, or to propose a flight themselves. This had resulted in some private pilots establishing themselves as quasi-public transport operators, unlicensed and without the requisite expertise to conduct such operations safely. The Committee shared the Airport company’s view that this is hazardous and undesirable from a security perspective. Although no action had yet been taken by the Airport, such flights would be likely to be prohibited from using the Airport. 7.03 RAF Northolt - referring to paragraph 4.02 above, members were informed that the Airport company had received no response to its letter to the Civil Aviation Authority which had enclosed its consultant’s report setting out the safety issues at RAF Northolt. The Airport Managing Director advised, however, that he had subsequently been informed that the substantive reply would be received shortly. I look forward to hearing at the next meeting if the company has, in fact, had the reply. John Bowden

Chairman

     

                   

           Report to  London Biggin Hill Airport Biggin Hill Kent TN16 3BN  A11103‐R01‐DR April 2018 

LONDON BIGGIN HILL AIRPORT

ANNUAL REPORT 2017 

 

A11103‐R01‐DR April 2018   

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Bickerdike  Allen  Partners  LLP  is  an  integrated 

practice of Architects, Acousticians, and Construction 

Technologists, celebrating over 50 years of continuous 

practice. 

Architects: Design and project management services 

which cover all stages of design,  from  feasibility and 

planning  through  to  construction  on  site  and 

completion. 

Acoustic  Consultants:  Expertise  in  planning  and 

noise, the control of noise and vibration and the sound 

insulation and acoustic treatment of buildings. 

Construction Technology Consultants: Expertise in 

building  cladding,  technical  appraisals  and  defect 

investigation  and  provision  of  construction  expert 

witness services. 

 

 

 

 

 

This report and all matters referred to herein remain confidential to the Client unless specifically authorised otherwise, when reproduction and/or publication is verbatim and without abridgement. This report may not be reproduced in whole or in part or relied upon in any way by any third party for any purpose whatsoever without the express written authorisation of Bickerdike Allen Partners LLP. If any third party whatsoever comes into possession of this report and/or any underlying data or drawings then they rely on it entirely at their own risk and Bickerdike Allen Partners LLP accepts no duty or responsibility in negligence or otherwise to any such third party. Bickerdike Allen Partners LLP hereby grant permission for the use of this report by the client body and its agents in the realisation of the subject development, including submission of the report to the design team, contractor and sub‐contractors, relevant building control authority, relevant local planning authority and for publication on its website. 

 

   

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Contents  Page No.

1.0  Introduction .................................................................................................................................... 4 

2.0  The Airport ..................................................................................................................................... 4 

3.0  Noise Contours .............................................................................................................................. 5 

4.0  RSIS Eligibility ............................................................................................................................... 6 

5.0  Noise from individual Aircraft Operations ...................................................................................... 6 

6.0  Summary ....................................................................................................................................... 7 

 

 

 

Figure A11103/R01/01:    2017 Summer Daytime (07:00‐23:00) Noise Contours 

(57, 63, & 69 dB LAeq,16h)  

Figure A11103/R01/02:    2017 Summer Late Evening (22:00‐23:00) Noise Contours 

(57, 63, & 69 dB LAeq,1h)  

Figure A11103/R01/03:    2017 Summer Early Morning (06:30‐07:00) Noise Contours 

(57, 63, & 69 dB LAeq,30mins)  

 

 

Appendix A:      Glossary of Acoustic and Aviation Terminology 

Appendix B:      Noise Contour Methodology 

Appendix C:      Validation of Noise Contour Methodology 

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1.0 INTRODUCTION 

Bickerdike Allen Partners LLP (BAP) have been retained by London Biggin Hill Airport (LBHA) to 

provide information in relation to noise for an annual report. This comprises: 

airborne aircraft noise contours for the 92 day summer period in 2017, 

dwellings eligible under the airport’s Residential Sound Insulation Scheme (RSIS), 

an assessment of compliance with the early morning period maximum noise limits for 

aircraft. 

A glossary of acoustic and aviation terms can be found in Appendix A.  

2.0 THE AIRPORT 

London Biggin Hill Airport lies immediately to the north of Biggin Hill village, with much of the 

remaining area immediately surrounding the airport primarily farmland. New Addington lies a 

distance to the west of the airport, and Orpington a distance to the northeast. 

The  airport  has  a  single  operational  runway which  is  1.8km  long  and  aligned  southwest–

northeast. The former cross runway, which is orientated approximately east west, is now only 

used by some helicopter movements.  

On 1st May 2017 the airport operating hours were revised following agreement with the London 

Borough  of  Bromley.  The  agreement  included  a  number  of measures  that  the  airport  are 

required to undertake. For example the airport has installed a dedicated noise monitoring and 

track keeping system, a Bruel and Kjaer ANOMS Noise Desk system, which is directly accessible 

to the public. Noise contours reflecting the aircraft activity have also been regularly produced 

for the airport and reported to the Noise and Safety Sub Committee of the Biggin Hill Airport 

Consultative Committee. 

The agreement also includes the introduction of an area limit for the summer period daytime 

noise contour at a value of 57 dB LAeq,T . For the daytime, late evening and early morning periods 

there are also 57 dB LAeq,T contour areas that the airport has to use reasonable endeavours to 

keep below. 

A Residential Sound Insulation Scheme (RSIS) has also been introduced which provides a grant 

for sound insulation enhancement to bedroom windows of those residences at which a noise 

level in excess of 90 dB SEL occurs at an annual average frequency of once or greater per early 

morning period of (06h30 to 07h00). 

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The noise monitoring and track keeping system is also used to monitor the noise from individual 

flights. Where these exceed set noise levels during the early morning period of (06h30 to 07h00) 

the operators may be subject to fines, and restrictions may be introduced on operations by the 

aircraft type. 

The 2017 performance against these three measures is detailed in the following sections. 

3.0 NOISE CONTOURS 

Noise contours have been produced for the 2017 summer period using the actual movements 

during period, 16th  June  to 15th  September  inclusive.  This  is  the usual period  taken when 

producing noise  contours  in  the UK and usually  represents a worst  case as airport  traffic  is 

generally highest during the summer. 

The noise contours have been produced, as detailed in Appendix B, using the Federal Aviation 

Administration (FAA) prediction methodology, the Integrated Noise Model (INM) version 7.0d. 

The methodology has been validated using measured noise data  from  the Noise Monitoring 

Terminals (NMTs) installed at LBHA, as detailed in Appendix C. 

The  daytime  contours  are  shown  in  Figure  A11103‐R01‐01  and  compared  with  a  contour 

indicative of the area limit, and one indicative of the reasonable endeavours area limit. The late 

evening and early morning contours are shown in Figures A11103‐R01‐02 and A11103‐R01‐03 

respectively with contours indicative of their reasonable endeavours limits. 

The contour areas, at 57 dB LAeq,T,  are given in Table 1 and compared with their respective limits. 

Also included are the areas of the 63 dB and 69 dB contours which are also shown on the figures. 

Contour (LAeq,T) 

Summer Contour Area by Period (km2)  

Daytime 

(07:00‐23:00) 

Late Evening 

(22:00‐23:00) 

Early Morning 

(06:30‐07:00) 

2017 Summer: 57 dB   2.1  0.3   0.5 

2017 Summer: 63 dB  0.7  0.1  0.2 

2017 Summer: 69 dB  0.3  <0.1  <0.1 

Daytime Limit: 57 dB  4.3  ‐  ‐ 

Reasonable Endeavours Limits: 57 dB  2.9  1.3  2.2 

Table 1: Area of Noise Contours 

The 57 dB daytime  contour  is well within  the 4.3  km2   Daytime  limit, and  is within  limit of 

2.9 km2, which the airport are required to take reasonable endeavours to stay below. The late 

evening and early morning 57 dB contours are well below their respective limits of 1.3 km2 and 

2.2 km2, which the airport are required to make reasonable endeavours to stay below. 

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4.0 RSIS ELIGIBILITY 

The  Residential  Sound  Insulation  Scheme  (RSIS)  provides  a  grant  for  sound  insulation 

enhancement to bedroom windows of those residences at which a noise level in excess of 90 dB 

SEL occurs at an annual average frequency of once or greater per early morning period of (06h30 

to 07h00). 

In the period 1st May to 31st December 2017, since the airport operating hours were revised, 

there were 107 movements  in  the early morning period. This equates  to an average of 0.5 

movements  per  night, which  is  too  few  to  reach  the  eligibility  threshold  of  once  per  early 

morning period on average. No properties are therefore currently eligible under the RSIS. 

5.0 NOISE FROM INDIVIDUAL AIRCRAFT OPERATIONS 

The noise monitoring and track keeping system includes Noise Monitoring Terminals (NMTs) to 

the north (NMT1) and south (NMT2) of the airport in locations overflown. The results obtained 

from the NMTs for individual aircraft operating during the early morning period (06:30‐07:00) 

have been compared to the noise limits set out in Table 2 below. 

Where an aircraft operation  is found to have exceeded the noise  limits at either NMT  in the 

early morning  period,  the  incident will  be  raised with  the  Safety  and Noise  Review  Board 

(SANARB) and after their consideration the operator may be subject to a fine. 

Where an aircraft  type  is  found  to consistently exceed  the noise  limits at either NMT, early 

morning operations by that aircraft type will be curtailed until  it can be demonstrated that it 

can routinely comply with the limits. 

NMT No.  Operation Noise Limits,  

dB(A) SEL 

1 Arrivals  86 

Departures  96 

2 Arrivals  92 

Departures  94 

Table 2: Early Morning Period Operation Noise Limits 

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In 2017 the early morning operation noise  limits were exceeded on 2 occasions as shown  in 

Table 3 below. Both of the exceedances were from helicopter arrivals measured at NMT1. 

NMT  Operation  Date  Time  Aircraft Type Noise Level, 

dB(A) SEL 

Noise Limit,

dB(A) SEL 

1  Arrival  30th Nov  06:49 Aerospatiale AS‐355   89.5  86 

1  Arrival  4th Dec  06:30 Augusta Westland AW109   88.9  86 

Table 3: Early Morning Period Operation Noise Limit Exceedances 

To check if these aircraft types will consistently exceed the early morning noise limits all their 

results, including those that occurred during the daytime have been considered as detailed in 

Table 4. The average noise  level  for  the Aerospatiale AS‐355  is 82.9 dB(A) SEL, which  is well 

within the NMT1 arrivals noise limit of 86 dB. The average noise level for the Augusta Westland 

AW109 is 84.0 dB(A) SEL, which is also within the limit. This indicates that both aircraft types do 

not consistently exceed the early morning operations noise limit. 

NMT  Operation  Aircraft Type Number of NMT 

Results 

Average Noise Level,

dB(A) SEL 

1  Arrival  Aerospatiale AS‐355  28  82.9 

1  Arrival  Augusta Westland AW109 430  84.0 

Table 4: Typical Noise Levels of Aircraft Types which Exceeded the Noise Limits 

6.0 SUMMARY 

BAP have produced noise contours for the 92 day summer period in 2017 for London Biggin Hill 

Airport using the actual aircraft movements. The results of the contouring exercise have been 

reported  and  figures  showing  the extent of  the  contours  relative  to  the  airport have been 

produced. The area of the 57 dB contour for the daytime period is well below the contour area 

limit, and is within the limit which the airport are required to take reasonable endeavours to 

stay below. The late evening and early morning 57 dB contours are well below their respective 

limits, which the airport are required to make reasonable endeavours to stay below. 

An assessment of dwellings eligible under the airport’s residential sound insulation scheme has 

been undertaken and found that there were insufficient movements in the early morning period 

to meet the eligibility requirements, therefore there are no eligible dwellings. 

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An assessment of early morning period operation noise  limits for aircraft as measured at the 

NMTs has been undertaken. The noise limits were exceeded on two occasions in 2017, both by 

helicopter arrivals measured at NMT1. The average noise  levels for both helicopter types are 

however below the noise limits, indicating that both aircraft types do not consistently exceed 

the early morning operations noise limits. 

 

 

 

Duncan Rogers  David Charles  Peter Henson 

for Bickerdike Allen Partners  Associate  Partner 

This drawing contains Ordanance Survey data © CrownCopyright and database right 2017.

DRAWN: CHECKED:

DATE: SCALE:

FIGURE No:

121 Salusbury Road, London, NW6 6RGEmail: mail@bickerdikeallen.com T: 0207 625 4411www.bickerdikeallen.com F: 0207 625 0250

REVISIONS

Biggin Hill AirportRegular Reporting

Airborne Aircraft Noise Contours2017 SummerDaytime (07:00-23:00)

DR DC

April 2018 1:50000@A4

A11103-R01-01

L Noise ContoursAeq,16h

57 dB 2017 Summer63 dB 2017 Summer69 dB 2017 Summer

57 dB Indicative Limit Contour

57 dB Reasonable EndeavorsIndicative Limit Contour

57 dB 2017 Summer63 dB 2017 Summer69 dB 2017 Summer

57 dB Reasonable EndeavorsIndicative Limit Contour

This drawing contains Ordanance Survey data © CrownCopyright and database right 2017.

DRAWN: CHECKED:

DATE: SCALE:

FIGURE No:

121 Salusbury Road, London, NW6 6RGEmail: mail@bickerdikeallen.com T: 0207 625 4411www.bickerdikeallen.com F: 0207 625 0250

REVISIONS

Biggin Hill AirportRegular Reporting

Airborne Aircraft Noise Contours2017 SummerLate Evening (22:00-23:00)

DR DC

April 2018 1:50000@A4

A11103-R01-02

L Noise ContoursAeq,1h

57 dB 2017 Summer63 dB 2017 Summer69 dB 2017 Summer

57 dB Reasonable EndeavorsIndicative Limit Contour

This drawing contains Ordanance Survey data © CrownCopyright and database right 2017.

DRAWN: CHECKED:

DATE: SCALE:

FIGURE No:

121 Salusbury Road, London, NW6 6RGEmail: mail@bickerdikeallen.com T: 0207 625 4411www.bickerdikeallen.com F: 0207 625 0250

REVISIONS

Biggin Hill AirportRegular Reporting

Airborne Aircraft Noise Contours2017 SummerEarly Morning (06:30-07:00)

DR DC

April 2018 1:50000@A4

A11103-R01-03

L Noise ContoursAeq,30m

A11103‐R01‐DR April 2018 

A.1 

 

 

 

 

APPENDIX A 

GLOSSARY OF ACOUSTIC AND AVIATION TERMINOLOGY

 

 

 

 

A11103‐R01‐DR April 2018 

A.2 

Sound 

This is a physical vibration in the air, propagating away from a source, whether heard or not. 

The Decibel, dB 

The unit used to describe the magnitude of sound is the decibel (dB) and the quantity measured 

is  the  sound pressure  level.  The decibel  scale  is  logarithmic  and  it  ascribes  equal  values  to 

proportional changes in sound pressure, which is a characteristic of the ear. Use of a logarithmic 

scale has the added advantage that  it compresses the very wide range of sound pressures to 

which the ear may typically be exposed to a more manageable range of numbers. The threshold 

of hearing occurs at approximately 0 dB (which corresponds to a reference sound pressure of 2 

x 10‐5 Pascals) and the threshold of pain is around 120 dB. 

The sound energy radiated by a source can also be expressed in decibels. The sound power is a 

measure of the total sound energy radiated by a source per second, in Watts. The sound power 

level, Lw is expressed in decibels, referenced to 10‐12 Watts. 

Frequency, Hz 

Frequency  is  analogous  to musical  pitch.  It  depends  upon  the  rate  of  vibration  of  the  air 

molecules which transmit the sound and is measure as the number of cycles per second or Hertz 

(Hz). The human ear is sensitive to sound in the range 20 Hz to 20,000 Hz (20 kHz). For acoustic 

engineering purposes, the frequency range is normally divided up into discrete bands. The most 

commonly used bands are octave bands, in which the upper limiting frequency for any band is 

twice the lower limiting frequency, and one‐third octave bands, in which each octave band is 

divided  into  three. The bands are described by  their centre  frequency value and  the  ranges 

which are typically used for building acoustics purposes are 63 Hz to 4 kHz (octave bands) and 

100 Hz to 3150 Hz (one‐third octave bands). 

A‐Weighting 

The sensitivity of the ear is frequency dependent. Sound level meters are fitted with a weighting 

network which approximates to this response and allows sound  levels to be expressed as an 

overall single figure value, in dB(A). 

A11103‐R01‐DR April 2018 

A.3 

Environmental noise descriptors 

Where noise levels vary with time, it is necessary to express the results of a measurement over 

a period of time in statistical terms. Some commonly used descriptors follow: 

LAeq,T  The  most  widely  applicable  unit  is  the  equivalent  continuous  A‐weighted  sound 

pressure level (LAeq,T). It is an energy average and  is defined as the level of a notional 

sound which  (over a defined period of  time, T) would deliver  the  same A‐weighted 

sound energy as the actual fluctuating sound. 

SEL  The total noise energy produced from a single noise event, normalised to a 1‐second 

duration. This is equal to LAeq + 10log(T). 

Sound transmission in the open air 

Most  sources  of  sound  can  be  characterised  as  a  single  point  in  space.  The  sound  energy 

radiated  is proportional  to  the surface area of a sphere centred on  the point. The area of a 

sphere is proportional to the square of the radius, so the sound energy is inversely proportional 

to  the square of  the  radius. This  is  the  inverse square  law.  In decibel  terms, every  time  the 

distance from a point source is doubled, the sound pressure level is reduced by 6 dB. 

Road traffic noise is a notable exception to this rule, as it approximates to a line source, which 

is represented by the line of the road. The sound energy radiated is inversely proportional to 

the area of a cylinder centred on the line. In decibel terms, every time the distance from a line 

source is doubled, the sound pressure level is reduced by 3 dB. 

Factors affecting sound transmission in the open air 

Reflection 

When  sound waves encounter a hard  surface,  such as  concrete, brickwork, glass,  timber or 

plasterboard, it is reflected from it. As a result, the sound pressure level measured immediately 

in front of a building façade is approximately 3 dB higher than it would be in the absence of the 

façade. 

Screening and diffraction 

If a solid screen  is  introduced between a source and receiver,  interrupting the sound path, a 

reduction in sound level is experienced. This reduction is limited, however, by diffraction of the 

sound  energy  at  the  edges  of  the  screen.  Screens  can  provide  valuable  noise  attenuation, 

however. For example, a timber boarded fence built next to a motorway can reduce noise levels 

on the land beyond, typically by around 10 dB(A). The best results are obtained when a screen 

is situated close to the source or close to the receiver. 

A11103‐R01‐DR April 2018 

A.4 

Meteorological effects 

Temperature and wind gradients affect noise transmission, especially over large distances. The 

wind  effects  range  from  increasing  the  level by  typically 2 dB downwind,  to  reducing  it by 

typically 10 dB upwind – or even more in extreme conditions. Temperature and wind gradients 

are variable and difficult to predict. 

Aviation terms 

Nominal Tracks 

Using recognised international design techniques, tracks across the ground can be delineated 

for departing and arriving aircraft. These tracks are nominal because they can be influenced by 

the wind, ATC instructions, the accuracy of navigational systems and the flight characteristics of 

individual  aircraft.  In UK  it  is usual  to permit  a 1500m  swathe  to be established  about  the 

nominal track for the purposes of assessing whether an aircraft has stayed on track. 

Dispersion 

Due to the effect of the wind, aircraft speed, and pilot choice differing aircraft tracks about the 

nominal track are flown; this is known as dispersion around a nominal track. 

Altitude 

Height of aircraft above sea level. 

Noise Footprint 

A noise contour which joins points on the ground which receive the same maximum noise level 

from the nearby airborne aircraft; often for night studies 90 dB(A) SEL is the level used. 

 

 

 

 

 

 

 

 

 

 

A11103‐R01‐DR April 2018 

B.1 

 

 

 

 

APPENDIX B 

NOISE CONTOUR METHODOLOGY 

 

 

 

 

A11103‐R01‐DR April 2018 

B.2 

NOISE CONTOUR METHODOLOGY INM Software 

The  noise  contours  have  been  produced  using  the  Federal  Aviation  Administration  (FAA) 

prediction software,  the  Integrated Noise Model  (INM) version 7.0d.   This evaluates aircraft 

noise in the vicinity of airport’s using flight track information, aircraft fleet mix, aircraft profiles 

and terrain data. The INM can be used to produce noise exposure contours as well as predict 

noise levels at specific user‐defined sites. 

London Biggin Hill Airport (LBHA) data relevant to the INM study is taken from the latest edition 

of the UK Aeronautical Information Package. 

A 3.0° approach angle is used for all aircraft, soft‐ground attenuation is assumed and the INM 

default headwind of 14.8 km/h is used. The local ground topography has been incorporated into 

the model.

Flight Tracks

A set of nominal tracks have been developed based on published procedures. These comprise  

one departure  route, one arrival  route and one circuit  route  from each end of  the  runway. 

Arrivals using Runway 21 make a straight approach from the north‐east to the runway. Arrivals 

using Runway 03 initially follow the same route as arrivals using Runway 21 before circling to 

the west of the airport and then lining up with Runway 03. 

Departures  on  Runway  03  turn  east  approximately  1.5km  after  the  end  on  the  runway. 

Departures on Runway 21 turn west shortly after the end of the runway, circle back and cross 

the runway at  its approximate mid‐point and then head east. Circuit routes for both runway 

ends are to the west of the airport. 

All aircraft on departure are allocated a departure route to follow. In practice, this route is not 

followed precisely by all aircraft. The actual pattern of departing aircraft is dispersed about the 

route’s main track. The degree of dispersion is normally a function of the distance travelled by 

an aircraft along the route after take‐off and also on the form of route. The INM model allows 

this dispersion about the departure tracks to be taken into account. The effect on the contours 

is to slightly widen but shorten the contours where departure noise dominates. 

When  considering  many  departures,  it  is  commonly  found  that  the  spread  of  aircraft 

approximates  to a normal distribution,  the shape or spread of which will vary with distance 

along  the  route.  A  simplified mathematical model  can  be  adopted  to  represent  a  normal 

distribution  of  events,  based  on  standard  deviations.  Aircraft  noise  modelling  commonly 

assumes that there are five dispersed tracks associated with each departure route. 

A11103‐R01‐DR April 2018 

B.3 

The allocation of movements adopted in this case to the main and sub tracks is as follows: 

53.3% departures along the main track; 

22.2% departures split equally along two inner sub tracks either side of the main track 

and offset by a distance of 1.355 standard deviations; 

1.15% departures split equally along two outer sub tracks either side of the main track 

and offset by a distance of 2.71 standard deviations. 

The resultant dispersion model for all routes is shown in Table B1. 

Distance from SOR (km) 

Outer Track Displacement (m) 

Distance from SOR (km) 

Outer Track Displacement (m) 

End of Runway  0  7.5  1007 

3.5  105  8.0  1109 

4.0  211  8.5  1184 

4.5  323  9.0  1260 

5.0  434  9.5  1324 

5.5  556  10.0  1387 

6.0  678  10.5  1444 

6.5  792  11.0 and above  1500 

7.0  905     

Table B1: Assumed Dispersion (All Departure Routes) 

Flight Profiles 

For departure movements the INM software offers a number of standard flight profiles for most 

aircraft  types,  particularly  for  the  larger  aircraft  types.  These  relate  to  different  departure 

weights which are greatly affected by the length of the flight, and consequently the fuel load. In 

the INM software this is referred to as the stage length. The stage length increases in increments 

of 500 nmi up to 1500 nmi and then in increments of 1000 nmi. The INM software assumes all 

aircraft take off with a full load irrespective of stage length. As the stage length increases, the 

aircraft has to depart with greater fuel, and so  its flight profile  is slightly  lower than when a 

shorter stage length is flown. 

For many of the aircraft types operating from LBHA, their small size results  in only one stage 

length  being  available.  For  the  remainder  the  stage  length  was  chosen  based  on  their 

destination.

A11103‐R01‐DR April 2018 

B.4 

Aircraft Operations

The aircraft movement data, provided by LBHA, has been assessed in relation to aircraft type, 

flight profile and runway usage for input into the Integrated Noise Model (INM) software.

The basis  for the 2017 noise contours are the actual movements during  the 92 day summer 

period, 16th June to 15th September inclusive. Detailed information was provided for all aircraft 

movements. The 113 movements by military aircraft, which were generally associated with the 

Festival of Flight in August, have been excluded. This leaves 13,573 movements in the daytime 

period  (07:00‐23:00), of which  38 occurred  in  the  late  evening  period  (22:00‐23:00),  and  a 

further 36 movements in the early morning period (06:30‐07:00). There were no movements in 

the period 23:00‐06:30.

The INM software includes noise information for many common aircraft types, but it does not 

include every aircraft  type. This means  that  substitutions are  required where an alternative 

aircraft type is used to model the actual type. For larger aircraft this generally does not involve 

a change but for the smaller types, and in particular the general aviation aircraft, substitutions 

occur. Where INM has no guidance, an aircraft type has been assigned based on the aircraft size 

and engine details. For a small number of aircraft their aircraft type was given as “ZZZZ” in the 

movement log. The aircraft types for these aircraft were determined using their registrations.

Table B2  gives  a  full  list  of  the  aircraft  type  codes,  as  provided  by  the  airport,  and  the 

corresponding  INM  aircraft  types  that  were  used  to model  the  aircraft.  This  includes  the 

substitutions made.

 

Aircraft Type Code 

INM Type Aircraft Type 

Code INM Type 

Aircraft Type Code 

INM Type 

8E  GASEPF  CW12  GASEPF  M209  GASEPF 

A019  A109[1]  CZAW  GASEPF  M20J  GASEPV 

A109  A109[1]  D250  GASEPF  M20K  GASEPV 

A119  A109[1]  D328  DO328  M20P  GASEPV 

A139  SA330J[1]  DA20  GASEPF  M20R  GASEPV 

A169  S76[1]  DA40  GASEPV  M20T  GASEPV 

A210  GASEPF  DA42  BEC58P  M6  GASEPF 

A22  GASEPF  DA62  BEC58P  MATA  GASEPF 

A318  A319‐131  DA90  BEC58P  MATS  GASEPF 

A319  A319‐131  DAK  DC3  MD50  H500D[1] 

A36  GASEPF  DC3  DC3  MD60  B407[1] 

A365  SA365N[1]  DFLY  BEC58P  MD90  B407[1] 

A565  SA365N[1]  DH1  GASEPF  MD92  B407[1] 

AA5  GASEPF  DH60  GASEPF  ME08  BEC58P 

AA53  GASEPF  DH8  DHC8  ME10  GASEPV 

AA5A  GASEPF  DH82  GASEPF  ME18  BEC58P 

AA5B  GASEPF  DH87  GASEPF  MESS  GASEPF 

A11103‐R01‐DR April 2018 

B.5 

Aircraft Type Code 

INM Type Aircraft Type 

Code INM Type 

Aircraft Type Code 

INM Type 

AA5C  GASEPF  DH90  BEC58P  MI24  Military 

AA5L  GASEPF  DHC1  GASEPF  MOR2  GASEPF 

AC11  GASEPV  DHC6  DHC6  MOTH  GASEPF 

AC14  GASEPV  DO24  BEC58P  MU2  CNA441 

AC95  CNA441  DO27  GASEPF  NG5  GASEPF 

AEST  BEC58P  DO28  GASEPF  OA28  PA28 

AG5B  GASEPF  DOVE  BEC58P  OV10  Military 

AH64  Military  DR10  GASEPF  P10  GASEPV 

AJET  Military  DR11  GASEPF  P149  CNA206 

AS32  S61[1]  DR14  GASEPF  P180[2]  DC3/SD330[3] 

AS35  SA355F[1]  DR15  GASEPF  P18A  GASEPF 

AS50  SA350D[1]  DR20  GASEPF  P210  CNA206 

AS55  SA355F[1]  DR21  GASEPF  P28  PA28 

AS65  SA365N[1]  DR25  GASEPF  P28A  PA28 

ASTR  IA1125  DR30  GASEPF  P28B  GASEPV 

AT6  GASEPV  DR40  GASEPF  P28R  GASEPV 

AT72  DO328  DR46  GASEPF  P28T  GASEPV 

AT75  DO328  DR49  GASEPF  P28U  GASEPV 

AUS  GASEPF  DR50  GASEPF  P2A  GASEPF 

AUST  GASEPF  DRAG  BEC58P  P30  PA30 

AW39  SA330J[1]  DRUF  SA365N[1]  P32A  GASEPV 

B06  B206L[1]  E121  DHC6  P32R  GASEPV 

B06L  B206L[1]  E135  EMB145  P32T  GASEPV 

B09  GASEPF  E145  EMB145  P46  GASEPV 

B100  CNA441  E170  EMB170  P46T  GASEPV 

B17  Military  E300  GASEPF  P51  BEC58P 

B190  1900D  E35L  EMB145  P68  BEC58P 

B200  GASEPF  E500  CNA20T  P68C  BEC58P 

B205  B212[1]  E50P  CNA510  P8A  PA28 

B206  B206L[1]  E545  CNA55B  PA18  GASEPF 

B207  GASEPF  E550  CNA55B  PA20  PA30 

B208  GASEPF  E55L  CNA55B  PA22  GASEPF 

B209  GASEPF  E55P[2]  CNA510  PA23  BEC58P 

B269  GASEPF  EA50  ECLIPSE500  PA24  GASEPV 

B350  CNA441  EC12  SA341G[1]  PA26  PA28 

B36T  GASEPV  EC13  EC130[1]  PA27  BEC58P 

B407  B407[1]  EC20  SA341G[1]  PA28  PA28 

B429  B429[1]  EC30  EC130[1]  PA29  PA30 

B461  BAE146  EC35  EC130[1]  PA30  PA30 

B462  BAE146  EC45  B429[1]  PA31  PA31 

B600  GASEPF  EC55  SA365N[1]  PA32  GASEPV 

B733  737300  EGKH  CNA172  PA34  BEC58P 

B737  737700  EGMD  BEC58P  PA38  GASEPF 

B738  737800  EGNE  PA28  PA39  PA30 

BA46  BAE146  EGSE  PA28  PA46  GASEPV 

BANS  GASEPF  EGTE  GASEPF  PAY1  PA31 

A11103‐R01‐DR April 2018 

B.6 

Aircraft Type Code 

INM Type Aircraft Type 

Code INM Type 

Aircraft Type Code 

INM Type 

BD20  GASEPF  EGTF  PA28  PAY2  PA31 

BDOG  CNA206  EGXP  Military  PAY3  PA42 

BE10  CNA441  EN28  R44[1]  PAY4  PA42 

BE19  1900D  EN48  H500D[1]  PC12[2]  CNA208 

BE20  CNA441  ERCO  GASEPF  PITS  GASEPF 

BE23  GASEPF  ESTR  GASEPF  PITT  GASEPF 

BE24  GASEPF  EUFI  Military  PIVI  GASEPF 

BE30  DO228  EUPA  GASEPF  PL4H  GASEPF 

BE33  GASEPV  EV97  GASEPF  PNR3  Military 

BE35  GASEPV  EVOT  CNA208  PNR4  GASEPF 

BE36  GASEPV  EXC  R22[1]  PPA3  PA31 

BE40  MU3001  EXEC  R22[1]  PREM  LEAR35 

BE55  BEC58P  EXHL  R22[1]  PREN  CNA206 

BE58  BEC58P  EXPL  B407[1]  PRM1  LEAR35 

BE60  PA31  EXTR  GASEPF  PROC  GASEPF 

BE76  BEC58P  F16  Military  PS28  GASEPF 

BE90  CNA441  F2TH[2]  CL600  PT2S  GASEPF 

BE9L  CNA441  F406  CNA441  PTS1  GASEPF 

BE9T  CNA441  F70  F10062  PTS2  GASEPF 

BF10  BEC58P  F8L  GASEPF  PUP  GASEPF 

BL17  GASEPV  F900[2] CNA680/ 

F100062[3] R200  GASEPF 

BL8  GASEPF  FA10  LEAR35  R21  GASEPF 

BN2T  1900D  FA20  FAL20  R22  R22[1] 

BO08  GASEPF  FA22  GASEPF  R300  GASEPF 

BO20  GASEPF  FA50  F10062  R44  R44[1] 

BO6  B206L[1]  FA78  F10062  R66  R44[1] 

BO7  B407[1]  FA7X[2]  F10062  RANG  B206L[1] 

BREE  GASEPF  FA8X  F10062  RAPI  BEC58P 

BREZ  GASEPF  FALC  GASEPF  RB20  GASEPF 

BS10  CNA441  G109  GASEPF  REAR  GASEPF 

BU81  GASEPF  G115  GASEPF  RJ70  BAE146 

BULL  CNA206  G150  IA1125  RJ85  BAE146 

C10T  CNA206  G280  CL601  RV10  GASEPF 

C115  CNA172  G58  BEC58P  RV3  GASEPF 

C120  GASEPF  G8L  GASEPF  RV4  GASEPF 

C130  Military  GA7  BEC58P  RV6  GASEPF 

C150  CNA172  GA8  CNA206  RV7  GASEPF 

C152  CNA172  GALX  CNA750  RV8  GASEPF 

C172  CNA172  GAZL  SA341G[1]  RV9  GASEPF 

C177  CNA172  GL5  GV  RWIN  GASEPV 

C180  CNA206  GL5T  GV  S05R  GASEPF 

C182  CNA182  GLAS  GASEPF  S22T  GASEPV 

C183  CNA182  GLEX[2]  GV  S2A  GASEPF 

C185  CNA206  GLF2  GII  S2B  GASEPF 

C195  GASEPV  GLF3  GIIB  S2C  GASEPF 

A11103‐R01‐DR April 2018 

B.7 

Aircraft Type Code 

INM Type Aircraft Type 

Code INM Type 

Aircraft Type Code 

INM Type 

C196  GASEPV  GLF4  GIV  S355  SA355F[1] 

C206  CNA206  GLF5[2]  GV  S365  SA365N[1] 

C208  CNA208  GLF6  GV  S600  GASEPF 

C210  CNA206  GROB  GASEPF  S76  S76[1] 

C24R  GASEPF  GULL  GASEPV  S76C  S76[1] 

C25A[2]  CNA525C  GX  GASEPF  S92  S70[1] 

C25B  CNA525C  GY80  GASEPV  SAAB  Military 

C25C  CNA525C  GYRC  GASEPF  SB20  HS748A 

C25M  CNA525C  GYRO  GASEPF  SB39  Military 

C295  Military  H125  LEAR35  SCOU  Military 

C3  GASEPF  H25A  LEAR35  SCRU  GASEPF 

C303  BEC58P  H25B[2] LEAR35/ 

CNA680[3] SCRV  GASEPF 

C310  BEC58P  H25C  LEAR35  SE22  GASEPV 

C335  BEC58P  H269  R22[1]  SF34  SF340 

C337  BEC58P  H369  H500D[1]  SIRA  GASEPF 

C340  BEC58P  H500  H500D[1]  SK76  S76[1] 

C406  CNA441  H55  SA365N[1]  SKAR  GASEPF 

C410  BEC58P  H60  Military  SKYA  GASEPF 

C414  BEC58P  HA4T  CL600  SPIT  BEC58P 

C42  GASEPF  HARM  GASEPF  SPOR  GASEPF 

C421  BEC58P  HARV  GASEPV  SPRT  GASEPF 

C425  CNA441  HAWK  Military  SR15  GASEPF 

C441  CNA441  HDJT  CNA510  SR20  GASEPV 

C500  CNA500  HIND  Military  SR22  GASEPV 

C501  CNA500  HORN  GASEPF  SRUZ  GASEPF 

C510[2]  CNA510  HR20  GASEPF  ST22  GASEPV 

C525[2]  CNA525C  HU50  H500D[1]  ST75  GASEPV 

C550  CNA500  HURI  BEC58P  STMP  GASEPF 

C551  CNA500  HURR  BEC58P  SV4  GASEPF 

C55B  CNA55B  HUSK  GASEPF  SV4A  GASEPF 

C56  MU3001  HVRD  GASEPV  SVG  GASEPF 

C560  MU3001  J3  GASEPF  SW3  CNA441 

C56L  PA31  J328  CL600  SW4  DHC6 

C56X[2]  CNA560XL  J400  GASEPF  T210  CNA20T 

C650  CIT3  JAB  GASEPF  T6  GASEPV 

C680[2] CNA680/ 

CNA750[3] JAB1  GASEPF  TB10  GASEPF 

C68A  CNA680  JAB4  GASEPF  TB20  GASEPV 

C7  GASEPF  JABA  GASEPF  TBM7  CNA208 

C72R  CNA172  JABI  GASEPF  TBM8  CNA208 

C750  CNA750  JABU  GASEPF  TBM9  GASEPF 

C77R  CNA172  JOD  GASEPF  TFUN  GASEPV 

C82R  CNA182  JODE  GASEPF  TOBA  GASEPF 

CA10  GASEPF  JODL  GASEPF  TRAV  GASEPF 

CAP1  GASEPF  KL07  GASEPF  TRIG  GASEPF 

A11103‐R01‐DR April 2018 

B.8 

Aircraft Type Code 

INM Type Aircraft Type 

Code INM Type 

Aircraft Type Code 

INM Type 

CESS  CNA172  L4  GASEPF  TRIN  GASEPV 

CHIP  GASEPF  LANC  Military  TRVL  GASEPF 

CI25  CNA172  LEZE  GASEPF  TUC  BEC58P 

CJ64  GASEPF  LGEZ  GASEPF  TUCA  BEC58P 

CJ6A  BEC58P  LIPP  BO105[1]  TWST  GASEPF 

CL30[2] CL600/ 

CNA680[3] LJ31  LEAR35  TYPH  Military 

CL35  CL601  LJ35  LEAR35  UH1  Military 

CL60  CL600  LJ40  LEAR35  V10  DHC6 

COL4  GASEPV  LJ45[2] LEAR35/ 

GIV[3] VA50  BEC58P 

COUP  GASEPF  LJ55  LEAR35  VANS  GASEPF 

CP10  GASEPF  LJ60  CNA55B  VARG  GASEPF 

CRJ2  CL601  LJ75[2] LEAR35/ 

EMB145[3] VEZE  GASEPF 

CROB  GASEPF  LNC2  GASEPF  W169  S76[1] 

CROZ  GASEPF  LONG  GASEPF  XL2  GASEPF 

CRUR  GASEPF  LUSC  GASEPF  XXL2  GASEPF 

CRUZ  GASEPF  LUSK  GASEPF  YAK  GASEPV 

CRV2  GASEPF  LYNX  Military  YK52  GASEPV 

CT  GASEPF  M020  GASEPV  Z326  GASEPF 

CTSL  GASEPF  M108  GASEPV  ZLIN  GASEPF 

CTSW  GASEPF  M109  BEC58P  

CUB  GASEPF  M20  GASEPV 

[1] Helicopter INM Type [2] Aircraft Type modified based on results of validation exercise [3] Different INM Types used to model arrivals and departures 

Table B2: Assignment of INM Aircraft Types to Aircraft Type Codes 

The  INM  software  does  not  contain  circuit  profile  information  for  two  of  the  aircraft  that 

performed  circuits at Biggin Hill Airport  in  the 2017  summer period. As a  result,  the  circuit 

movements for these aircraft have been modelled as another similar aircraft type for which the 

circuit profiles are contained within INM. Table B3 highlights these aircraft and the substitutions 

made. 

INM Type  INM Type used for Circuits 

PA28  CNA172 

PA30  BEC58P 

Table B3: Modifications to INM Circuit Profile Assumptions  

A11103‐R01‐DR April 2018 

B.9 

Table B4 gives a summary of the 2017 summer movements by INM aircraft type, following the 

approach in Tables B2 and B3. Aircraft and helicopters which made up less than 2% of the total 

movements and  less  than 5% of  the movements  in either  the early morning or  late evening 

period have been grouped under the “Other” headings.

INM Aircraft Type 

2017 Summer Movements 

Daytime 

(07:00‐23:00) 

Late Evening[1] 

(22:00‐23:00) 

Early Morning 

(06:30‐07:00) 

A109[2]  638  0  0 

BEC58P  1,372  2  1 

CL600  356  0  2 

CL601  88  0  0 

CNA172  1,958  1  3 

CNA208  303  1  4 

CNA510  629  4  2 

CNA525C  485  5  1 

CNA560XL  465  1  4 

EMB145  214  4  1 

F10062  202  0  0 

GASEPF  700  0  1 

GASEPV  821  3  1 

GIV  207  1  4 

GV  313  3  6 

LEAR35  313  6  0 

PA28  3,103  0  0 

Other  1,406  7  6 

Total  13,573  38  36 [1] Contained within the Daytime movements [2] Helicopter INM Type 

Table B4: Summary of Summer 2017 Movements 

A11103‐R01‐DR April 2018 

B.10 

Runway Usage 

The actual runway usage for each aircraft movement was used in the production of the noise 

contours, this has been summarised below in Table B5 for fixed wing aircraft and helicopters.

Operation  Runway Percentage of Summer 2017 Movements 

Fixed Wing Aircraft  Helicopters 

Arrivals 

03  10%  6% 

21  90%  68% 

Other[1]  ‐  26% 

Departures 

03  26%  12% 

21  74%  39% 

Other[1]  ‐  40% 

Circuits 

03  12%  0% 

21  88%  100% 

Other[1]  ‐  0% [1] Helicopter movements which didn’t use the runway. 

Table B5: Summary of Runway Usage in Summer 2017 

Validation of Noise Contour Methodology 

The initial validation exercise carried out in July 2017 has been updated using NMT data for the 

whole of 2017, from NMTs 1 and 2, which lie to the north and south of the airport respectively. 

For the validation exercise the measured noise  levels for the key aircraft types at LBHA were 

compared with  those predicted by  the  INM and adjustments were made  to  the predictions 

where necessary. Full details of the validation exercise are given in Appendix C. 

 

 

A11103‐R01‐DR April 2018  C.1  

 

 

 

 

APPENDIX C 

VALIDATION OF NOISE CONTOUR METHODOLOGY 

 

 

 

 

A11103‐R01‐DR April 2018  C.2  

INTRODUCTION 

A validation of the 2017 noise contour methodology for London Biggin Hill Airport (LBHA) using 

measured aircraft noise  levels has been carried out. This has  involved the comparison of the 

measured noise levels of individual aircraft operations at the fixed Noise Monitoring Terminals 

(NMTs) during 2017, with the predicted noise levels for those operations using the Integrated 

Noise Model (INM) version 7.0d. 

NMT1 is located around 1 km north east of the northern end of the runway and NMT2 is located 

around 1 km to the south west of the southern end of the runway. 

Due to prevailing weather conditions, and the navigation facilities currently  in place at LBHA, 

there are relatively few arrivals on to Runway 03 and therefore there are few measured results 

for arrivals at NMT2. Departures from Runway 03 turn shortly after the end of the runway which 

introduces  a  degree  of  variability  in  their  local  flight  path  and  therefore  variability  in  their 

distance to NMT2. This assessment therefore concentrates on the results from NMT1 where 

there is greater consistency. 

Seventeen aircraft types have been selected to be analysed  in the validation exercise. These 

were chosen based upon the aircraft types’ relative contribution to the noise contours, when 

considering the total number of flights by each aircraft type and the noise level of the flights, 

and the availability of a sufficient number of measured results to determine reliable average 

noise levels for the aircraft types. 

MEASURED AND PREDICTED NOISE LEVELS 

For  each  aircraft  type  there  are  typically  four  sets  of  measured  results,  for  arrivals  and 

departures,  at  each  of  the  two  monitors.  However  as  discussed  above  the  assessment 

concentrates on the measurements at NMT1. 

For the individual movements within a set there is some natural variation, so for example every 

arrival by an aircraft type does not produce exactly the same noise level. There are a number of 

factors which contribute to this, in particular the weather conditions, and for departures, the 

weight of the aircraft. Average measured SELs are therefore used, and are compared with the 

predicted noise levels from INM 7.0d in Table C1 below. For three of the aircraft type codes the 

INM does not contain the specific aircraft type, nor does it suggest a substitution. Therefore for 

these a similar aircraft type available  in the  INM has been used, as has been done for other 

aircraft types as set out in Appendix B. 

A11103‐R01‐DR April 2018  C.3  

Aircraft Type Code 

Operation Measured   Default INM 

Type Predicted SEL (dB) 

Difference Predicted to 

Measured (dB) Avg. SEL (dB)  No. 

C25A A  82.3  222  CNA525C[1]  80.9  ‐1.4 

D  88.0  89  CNA525C[1]  89.1  +1.1 

C510 A  77.6  344  CNA510  81.2  +3.6 

D  85.6  203  CNA510  86.2  +0.6 

C525 A  80.9  145  CNA525C  80.9  0.0 

D  87.1  67  CNA525C  89.1  +2.0 

C56X A  83.4  453  CNA560XL  85.7  +2.3 

D  81.9  222  CNA560XL  86.2  +4.3 

C680 A  80.4  121  CNA680  81.3  +0.9 

D  84.9  54  CNA680  88.4  +3.5 

CL30 A  80.4  98  CL601  83.4  +3.0 

D  87.0  47  CL601  89.4  +2.4 

E55P A  81.1  142  CNA510[1]  81.2  +0.1 

D  83.7  53  CNA510[1]  86.2  +2.5 

F2TH A  81.5  112  CL600  82.4  +0.9 

D  87.9  49  CL600  90.7  +2.8 

F900 A  81.2  101  F10062  86.1  +4.9 

D  93.2  48  F10062  93.4  +0.2 

FA7X A  83.0  121  F10062  86.1  +3.1 

D  90.8  48  F10062  93.4  +2.6 

GLEX A  81.6  134  GV  84.1  +2.6 

D  89.9  52  GV  90.3  +0.4 

GLF5 A  81.2  99  GV  84.1  +2.9 

D  87.6  33  GV  90.3  +2.7 

H25B A  84.1  161  LEAR35  83.1  ‐1.0 

D  87.7  79  LEAR35  96.3  +8.6 

LJ45 A  81.9  120  LEAR35  83.1  +1.2 

D  84.6  65  LEAR35  96.3  +11.7 

LJ75 A  82.0  121  LEAR35[1]  83.1  +1.1 

D  82.0  65  LEAR35[1]  96.3  +14.3 

P180 A  94.5  48  SD330  84.2  ‐10.3 

D  91.5  26  SD330  89.8  ‐1.7 

PC12 A  85.1  183  CNA208  87  +1.9 

D  80.8  65  CNA208  82.2  +1.4 [1] No default INM aircraft type or recommended substitution available. 

Table C1: Measured and Default Predicted Noise Levels at NMT1  

A11103‐R01‐DR April 2018  C.4  

As can be seen in the above table, the INM default prediction is over‐predicting the noise levels 

for most aircraft types, with under predictions in only a few cases. There are particularly large 

over predictions  for departures by  the H25B,  LJ45  and  LJ75,  and  a particularly  large under 

prediction for arrivals by the P180. 

Approach to Validation 

The approach to  introducing validation modifications has been to only change from the  INM 

default type when the measured results show clear divergence, i.e. an apparent prediction error 

in excess of 1.0 dB. If the type has historically been modified from the default type, then the 

approach has been to only change from the previous validation when the change in noise level 

is in excess of 0.5 dB. 

Comparison of Measured and Validated Noise Levels 

All of the seventeen aircraft types have had modifications made compared to the default INM 

prediction. This involves either a change to the INM aircraft type used to model the aircraft or 

the application of a movement multiplier which has the same effect as adjusting the modelled 

noise  level.  In  a  small number of  cases both  types of modification have been  applied.  The 

modifications made are detailed in Table C2 below. 

All of the modifications have the effect of reducing the difference between the measured and 

predicted noise levels, with the majority of differences being below 1 dB once the validation is 

applied.  In a small number of cases the difference  is greater than 1 dB, but all are  less than 

1.5 dB. These are due to aircraft which were validated previously, whose measured noise level 

hasn’t changed sufficiently to warrant changing the previous modification. 

A11103‐R01‐DR April 2018  C.5  

Aircraft Type Code 

Operation Measured 

Avg. SEL (dB) Validated INM 

Type Movement Multiplier 

Predicted SEL (dB) 

Difference Predicted to 

Measured (dB) 

C25A A  82.3  CNA525C  1.3  82.0  ‐0.2 

D  88.0  CNA525C  1  89.1  +1.1 

C510 A  77.6  CNA510  0.4  77.2  ‐0.3 

D  85.6  CNA510  1  86.2  +0.6 

C525 A  80.9  CNA525C  1  80.9  +0.0 

D  87.1  CNA525C  0.7  87.6  +0.5 

C56X A  83.4  CNA560XL  0.6  83.5  +0.1 

D  81.9  CNA560XL  0.4  82.2  +0.3 

C680 A  80.4  CNA680  1  81.3  +0.9 

D  84.9  CNA750[1]  0.8  84.9  0.0 

CL30 A  80.4  CL600[1]  0.6  80.2  ‐0.3 

D  87.0  CNA680[1]  0.7  86.9  ‐0.2 

E55P A  81.1  CNA510  1  81.2  +0.1 

D  83.7  CNA510  0.6  84.0  +0.3 

F2TH A  81.5  CL600  1  82.4  +0.9 

D  87.9  CL600  0.5  87.7  ‐0.2 

F900 A  81.2  CNA680[1]  1  81.3  +0.1 

D  93.2  F10062  1  93.4  +0.2 

FA7X A  83.0  F10062  0.5  83.1  +0.0 

D  90.8  F10062  0.6  91.2  +0.3 

GLEX A  81.6  GV  0.6  81.9  +0.3 

D  89.9  GV  1  90.3  +0.4 

GLF5 A  81.2  GV  0.5  81.1  ‐0.1 

D  87.6  GV  0.5  87.3  ‐0.3 

H25B A  84.1  LEAR35  1  83.1  ‐1.0 

D  87.7  CNA680[1]  0.8  87.4  ‐0.2 

LJ45 A  81.9  LEAR35  1  83.1  +1.2 

D  84.6  GIV[1]  0.8  84.7  +0.1 

LJ75 A  82.0  LEAR35  1  83.1  +1.1 

D  82.0  EMB145[1]  1  82.0  0.0 

P180 A  94.5  DC3[1]  1  94.4  ‐0.1 

D  91.5  SD330  1.4  91.3  ‐0.2 

PC12 A  85.1  CNA208  0.6  84.8  ‐0.3 

D  80.8  CNA208  1  82.2  +1.4 

[1] Change in INM aircraft type 

Table C2: Measured and Validated Noise Levels at NMT1 

A11103‐R01‐DR April 2018  C.6  

SUMMARY 

The validation of noise contour methodology at London Biggin Hill Airport has been carried out 

by checking predicted noise levels against the measured noise levels obtained from the Airport’s 

noise monitoring system. 

The  validation  exercise  has  taken  into  account  almost  4,000  individual  aircraft  noise 

measurements.  This  has  identified  the  need  to  modify  the  default  INM  assumptions  for 

seventeen of the loudest and most common aircraft types at LBHA.