This submission is a component of Teddington Action Group’s (TAG) response to Heathrow Airport’s Airport Expansion Consultation launched on 18 June 2019. Its focus is on Noise. Related TAG submissions address topics such as Air Quality, Carbon and Climate Change.

TAG has been a member the Heathrow Community Noise Forum (HCNF) since its inception in 2015, and its members have given evidence to Parliament’s Transport Select Committee and All Party Parliamentary Group (APPG) on Heathrow Expansion. TAG has also been party to legal challenges in connection with Heathrow expansion, as well as presenting conference papers on aviation noise and health impacts and submitting evidence to ICCAN.

General Feedback

TAG’s overriding view of Heathrow’s DCO PEIR consultation material, exhibitions and the feedback questionnaire is that, as a package, they form an inadequate and deficient basis for either informing a general public (which will be very significantly adversely affected by Heathrow’s expansion plans) or for receiving feedback. In many respects the information contained in the consultation material is misleading and incomplete, despite the huge bulk (circa 17,500 pages) of material presented.

We have reached this opinion having regard to the use within the consultation documents of questionable and/or unsupportable assumptions, the lack of a robust evidence base supporting the analysis of noise impacts, the omission of essential information relating to potential outcomes (especially in relation to sensitivity testing) and the use of opaque metrics.

These deficiencies are serious as this is a statutory consultation and the last opportunity for the public to respond formally in advance of the Development Consent Order (DCO) application and subsequent Inquiry. Whilst the PEIR states that a lot of further information and analysis will be presented eventually to the Planning Inspectorate, this will be too late and consequently is an unacceptable basis for public engagement. Residents and other stakeholders are not being provided with vital information concerning the project’s potential impacts and in a number of ways, in our view, they are being misled. We believe this approach will result in ongoing legal challenges as the project progresses.

Noise and Health – General Comments


The lack of an appropriate evidence base


The PEIR environmental analysis, projected health impacts and cost benefit analysis have been undertaken in the absence of an appropriate or adequate evidence base. No Heathrow specific surveys or investigations have been carried out addressing the impact of the huge level of change and expansion proposed for the airport and its associated airspace.

The World Health Organisation (WHO) issued revised Environmental Noise Guidance (ENG) in 2018 recommending that major changes in aviation of the scale and nature being proposed in the ANPS should be assessed as follows:

“…It is therefore not possible to determine the “exact value” of %HA for each exposure level in any generalized situation. Instead, data and exposure–response curves derived in a local context should be applied whenever possible to assess the specific relationship between noise and annoyance in a given situation. If, however, local data are not available, general exposure–response relationships can be applied, assuming that the local annoyance follows the generalized average annoyance.

The consultation documentation is based entirely on SoNA 2014 (published in 2017). This was produced by the CAA, which has a remit to promote aviation growth, but no duties of care to protect health, wellbeing or the environment. The CAA, almost entirely funded by the aviation industry, is inherently conflicted when providing advice in relation to aviation’s environmental impact, especially in factors which could limit future growth. This was reflected in the Airports Commission’s recommendation to establish an Independent Noise Authority (a fully independent regulator) and the subsequent creation by the Government of the Independent Commission on Civil Aviation Noise (ICCAN) (albeit that this a weaker alternative without regulatory powers and subject to DfT funding).

The CAA has confirmed that SoNA 2014 was intentionally carried out as a static survey and that the effect of airspace change on public sensitivity was not investigated in its survey. However, the CAA subsequently accepted at the HCNF that change is a key factor in establishing aviation’s noise impact. It is self-evident that it is not appropriate to use SoNA 2014 – which was designed to cover the whole of the UK – as the primary basis for evaluating Heathrow expansion in a local context, most importantly as the ANPS represents the most significant expansion and radical changes in the use of airspace in aviation history in the UK – and probably worldwide.

Serious flaws contained in SoNA 2014 have been thrown into sharp relief by WHO ENG 2018 which recommends strongly against exposing populations to greater than 45dB Lden (equivalent to 43dB LAeq) – whereas SoNA assesses significant impacts to occur at 54dB LAeq. As established during the Parliamentary Transport Select Committee examination through FOI over 2 million people will experience significant increases in noise above 45dB LAeq, even as late as 2050 when a much quieter fleet is assumed. This impact has been confirmed as correct by the DfT.

The differences in SoNA’s findings and WHO advice in relation to noise levels are huge and irreconcilable.

No sustainable or reasonable justification has been produced for basing the DCO’s noise assessment on SoNA 2014, although the PEIR analysis is entirely dependent on it. Whilst the PEIR states that a review of the WHO 2018 advice will be undertaken before the DCO Inquiry this is far too late. The public will not have been made aware as to the impact on their health and wellbeing in the documentation that forms the basis for this consultation. In fact, for reasons that will be explained in this submission, it is considered the analysis that is provided in the PEIR is potentially highly misleading.

Inexplicably SoNA was set up to avoid considering impacts on populations at noise levels below 51dB LAeq, despite a wealth of international and local evidence that aviation’s noise impacts at lower levels are very material. Notwithstanding this, SoNA has formed part of the evidence base for setting the UK LOAEL (lowest observable adverse effect level) for aviation – a key metric and used extensively in the PEIR analysis – at 51dB LAeq.

By not considering impacts at lower levels of noise SoNA prejudged what the level of LOAEL should be. It is not supportable to use a LOAEL of 51dB LAeq for aviation, certainly not in the local context, and especially in the given situation that Heathrow is proposing an unprecedented expansion and radical changes in the use of airspace.

In addition an inappropriate threshold, the problem with setting a LOAEL based on a LAeq metric is that noise events can massively increase if planes become just a little less noisy. If individual plane events are a (still noisy and disturbing) 65dB then this would be equivalent  at 51dB LAeq to 224 planes in a 16hr day or 14 planes an hour i.e. one every 4.3 minutes on average before accounting for runway alternation and respite. Common sense shows that a lowest observable adverse effect level at 51 dB is not credible. Either LOAEL must be reduced substantially (as indicated by WHO ENG 2018) or an events based metric must also be used to define LOAEL at around 25 N>65dB events or lower a day. The lower of either the events or LAeq measure should define LOAEL.

In fact, in relation to the local context, Heathrow itself possessed clear local evidence that observable adverse annoyance begins far below 51dB LAeq in a report it commissioned from Anderson in relation to the 2014 PBN departure trails. These trials led to enormous levels of complaints and protest around Heathrow airport and they had to be abandoned early. This is highly relevant local evidence to the given situation Heathrow now proposes but has been ignored completely within the DCO PEIR documentation.


These trials used the concentrated performance-based navigation (PBN) technology that Heathrow intend to introduce to enable their flight path changes associated with expansion. The evidence relating to the trials produced by Anderson is therefore shows the most relevant ‘response derived in a local context’ relevant to the changes now proposed. These trials showed high levels of sensitivity down to 48dB LAeq and lower.

On the Easterly departure trials over high density populations no increases in LAeq could be found by the noise modelling yet complaints rocketed with 7000 people signing the Teddington Town petition to stop the them. This reinforces the view that the use of LAeq is NOT an adequate metric to measure annoyance for departures over London’s high-density population. A noise events or intermittency metric was found to show better correlation to sensitivity. This should have been highlighted by Heathrow’s appointed Noise Expert Review Group (NERG), yet is not mentioned.


These issues, with detailed analysis, have been highlighted by communities at the HCNF and presentations made which are available on the Heathrow website.


Problems with SoNA 2014 also arise from the fact that:

  • It was only peer reviewed by two handpicked experts (one of whom also had a leading role in opposing an earlier assessment of the impact of aviation noise indicating lower public sensitivity thresholds should apply (ANASE) and has subsequently been appointed by Heathrow to chair the ‘independent’ Noise Experts Review Group (NERG) that has endorsed the consultation material)
  • Its population sampling did not reflect the demographics of the population that will be impacted by Heathrow expansion
  • the population surveyed was self-selecting in that only people who already lived in areas that were exposed to significant aviation noise (and therefore to a substantial extent noise tolerant) were surveyed
  • its statistical analysis was flawed, culminating in LAeq average measures being favoured for legacy reasons over noise event numbers (intermittency).

It is known from information obtained under FOI, that early drafts of SoNA show that N>events correlated better with annoyance  but in the final version of the report the conclusions were changed. This is an extract from a draft report:

It seems quite possible that the CAA were more concerned about legacy policy implications than basing their conclusions on technical evidence.

SoNA notes that public sensitivity to aviation noise is increasing but does not look for the cause. It is likely the increasing number of overflights is a major factor in increasing public annoyance, notwithstanding that average noise levels across the aviation fleet might have been reducing.

The PEIR documentation follows the lead set by SoNA and does not show what the noise contours based on N>above would be. The most obvious plausible reason is that it is likely to show far higher numbers of people impacted and the policy aim ‘not to affect’ more people than today’ would not be met.  

Having regard to the above considerations we believe that the information and analysis included in the consultation documentation is incomplete as well as being founded on an inappropriate evidence base. For other reasons explained in following sections the noise information that has been provided could also be regarded as misleading.

Finally, in relation to the evidence base, it is known that a SoNA for Night was commissioned some time ago. However, it has not been released into the public domain. It is noted that publication was held up due to inaccuracies in the CAA’s ANCON noise modelling system but no reason has been given for the length of delay. Please see item 12.3 in the HCNF minutes – despite repeated requests no response or follow up has been received on this since 2017:


The PEIR noise contour maps and associated assumptions don’t indicate the real impacts

The PEIR includes ten ‘test cases’ in relation to predicted noise impacts on communities.

These are based solely on average LAeq noise metrics – a measure unintelligible to the general public and reliant entirely on input assumptions which are in themselves questionable, sensitive to small changes and capable of manipulation. No flight path information and no N>event analysis (even indicative) has been provided, both of which are fundamental to an understanding of the noise environment that will be experienced by the general public.

Certainly, no information or clear explanation is included explaining the differences in assumptions for the ‘test cases’.

However, the test cases all attempt to show, based on average noise contour maps (which have unreadable geographical locations and colouration), that after expansion significant areas of Heathrow’s hinterland will experience less noise than the 2013 base year by the 2035 peak. This outcome is entirely dependent on reliance on the LAeq metric, optimistic assumptions about quieter planes, a rapid rate of fleet transition, as well as a considerably slower build-up of flight numbers than assumed when the ANPS was presented to Parliament (and on which the economic case for Heathrow expansion was approved).

Regarding less noisy planes the analysis is based on Heathrow’s assumption of an average reduction in noise from aircraft of 0.4 dB a year. This compares with the Airports Commission’s assumption of noise reduction of 0.1 dB per annum. By compounding assumed reductions in aviation noise emissions to 2035, the apparent benefit is amplified to a great extent. The noise maps, even on a LAeq basis, could look very different if the implications of a more cautious reduction rate were assumed.

In fact there are challenges to introducing new aircraft technology and fleet transition rates need to be treated with caution. In addition, we are starting to see trade-offs, as can be seen from the DfT’s ‘Aviation 2050 – The Future of UK Aviation’ consultation material, noise is in competition with air quality (as well as cost of implementation). It references a report from the Institute of Sound and Vibration Research Department of Southampton University, which advises that, in order to reduce emissions, the design of jet engines is going to have to change. The report advises ‘Noise is unlikely to be any greater than equivalent turbofan aircraft, but importantly, is unlikely to be quieter as is often supposed.’


(see Competing Priorities section)

The claim in PEIR Volume 3 Chapter 17 Annex Para 2.4.6 and following graphic Table 2.5 that the noise Quota Count is likely to reduce from some 350,000 today to just 150,000 looks open to question on the evidence of Southampton University.

The PEIR states that it has considered a worst-case sensitivity scenario but does not show the results in the consultation material – on the basis Heathrow does not consider this outcome likely. However, this could show a far less optimistic outcome, which would have a significant impact on public opinion at this juncture.

It is not clear if the improvement numbers refer to EPNdB changes (which include addition of departure, arrival and lateral measurements sometimes called cumulative certified noise performance) or improvements in departure or arrival noise. The projections are also dependent on assumptions regarding the nature and timing of the fleet transition and ATM build-up. These aspects need clarification, accompanied by clear and comprehensive sensitivity analysis.

Whilst Heathrow has included a rudimentary sensitivity analysis, this only assumes a variance of 1 dB on departures and 0.5 dB on arrivals (up or down). From this the PEIR concludes a plus or minus 10-15% difference to the LOAEL and SOAEL exposed population. However, the implications arising from the base assumption regarding the factors referred to above could far exceed these levels of change.

What the sensitivity analysis that is included in the PEIR demonstrates is that small movements in the noise contours (and other factors such as the proportion of the population sensitive to aviation noise) will have huge consequences for the numbers of people adversely impacted by a third runway.  In any event, the reality, as evidenced in Anderson’s trials report and the WHO’s ENG, is that annoyance begins at far lower noise levels than the 51 dBLAeq LOAEL and that sensitivity is increasing.

It should be also be emphasised in connection with the PEIR contour maps, that the DfT has adopted N65 day and single mode analysis (also missing) as key supplementary metrics when major airspace changes are being considered. It is Government policy to show the impacts of airspace change. This information should have been presented to the public in these documents.

For example ‘Air Navigation Guidance 2017 – Guidance to the CAA on its environmental objectives when carrying out its air navigation functions, and to the CAA and wider industry on airspace and noise management.’ published by the DfT in October 2017 had objectives which included to ‘strengthen the UK’s airspace change process and its transparency, particularly with respect to how local communities are involved within it

Section 3 ‘Detailed guidance on assessing the potential environmental impacts of airspace change options’ states:

3.12 The CAA should also verify that sponsors have used any other noise metrics that may be appropriate for allowing communities to understand the noise impacts that could result from the proposed change. This could include the use of 100% mode contours for average noise or frequency-based metrics, or consideration of the interaction with other sources of aircraft noise, such as those from other local airports.

These metrics are not included in the PEIR documentation and therefore, having regard to ANG 17, communities have not been provided with reasonable information to respond to the consultation.

The ‘test case’ noise maps are also all based on a continuation of the current average operational modal split; 70:30 west to east. At the same time Heathrow is suggesting a change to the current westerly preference protocol in favour of ‘managed preference’.

This aspect is considered further later in this submission.

Current Noise Conditions over Teddington and adjoining areas

In order to set the context for responses to the specific topic areas set out in the consultation and to comment more generally on Heathrow’s proposals with expansion, it is important to understand how noise conditions currently affect people in Teddington.

According to the PEIR (and UK airspace policies based on SoNA), Teddington does not currently suffer observable adverse effects from aviation as it does not fall within the LOAEL 51 dB contour. On this basis, with expansion it would be regarded as a ‘newly affected’ area. The reality is very different, exposing the flaws of the overall average dB LAeq metric system and the UK LOAEL threshold.

Since the 1960s the Teddington area has fallen under four Noise Preferential Routes and is in fact severely impacted when the airport operates on easterly operations between 20-40% of the time (dependent on wind conditions).

The above extract is taken the Community Noise Reports for Strawberry Hill and the NPL produced by Anderson on behalf of Heathrow in 2016. These reports contain much information describing conditions when Teddington is actually overflown, rather than these impacts being obscured in the overall average LAeq metric.


Teddington is exposed to an average noise level of 54-57dB LAeq when Heathrow’s operations are on easterly mode. The reports show how between 2011 and 2015 flight paths over our area had shifted, become more concentrated and been used more intensively.

These changes have corresponded with a very high increase in the number of complaints from the area, demonstrating how overall average metrics do not reflect public annoyance and that the impacts of aviation ought to be evaluated when areas are actually overflown rather than averaged out over periods when they are not. There are direct implications to be drawn from this in relation to topic areas Runway Alternation, Directional Preference, the Night Flight proposals and Early Growth (IPAs), as well as non-acoustic factors not addressed in the PEIR concerning time of day – especially early morning and late evening flights.

In particular the intensive use of departure routes to the south and east of the airport very late at night – with around 20 flights (or more as other flight paths crossing the area audible at very high levels of noise) crammed into the last hour, invariably overrunning into the Recovery Period and beyond – causes enormous detrimental impact to health and wellbeing. Often, the Recovery Period accommodates 6-12 flights passing over Teddington between 11.00pm and midnight. The PEIR does not recognise or address these considerations.

The graphic below shows the number of planes passing over Strawberry Hill across the day (and how this has changed between 2011 and 2016).


The next graphic shows similar information for the NPL – with noise impacts also being heard over Strawberry Hill.


The screen shot below shows flights recorded on the 14 and 15 July 2019 by a resident in the centre of Teddington, using the flight tracking app Explane. It provides a stark example of the extreme levels of noise currently experienced very late into the evening – with devastating impacts on quality of life, sleeping patterns and health when the airport is on easterly operations. It should be noted that the modelled noise levels in Anderson’s report are significantly exceeded by Explane, which is understood to be  accurate to 1-2dB LAmax. This disparity also raises concerns relating to the reliability of modelled noise which goes into calculating LAeq levels, which forms the sole basis of analysis in the PEIR documentation.

Noise levels recorded by Explane

Anderson reported noise levels over Strawberry Hill

Future operations – concentrated flight paths using PBN

The PEIR states that the new airspace arrangements will be based on Performance Based Navigation (PBN). The Early Growth (IPA) proposals are entirely dependent on it. The PEIR does not contain or refer to any environmental assessment or strategy to deal with the extremely adverse impacts for communities that will be exposed to intensively used flight paths under highly concentrated PBN routes. The consultation material and the PEIR are seriously defective in this respect.

As noted earlier, Heathrow trialled certain PBN departure routes in 2014. These led to widespread protest and had to be abandoned early. Anderson’s 2015 report referred to earlier details the impacts.

Since the formation of the HCNF community groups have continued to challenge Heathrow, the CAA and NATS on how PBN can be introduced over highly densely populated areas without very serious detrimental health effects. None of the concerns and questions raised have been addressed.

This is what Heathrow stated in relation to PBN in response to a European consultation in 2016:

In fact, absolutely no research into the Social Impact of PBN trials in the UK or an environmental assessment have been undertaken. Heathrow, the CAA and NATS have simply buried their heads in the sand on an issue that will have devastating effects on overflown communities.

However, Community Groups have presented evidence to Heathrow at the HCNF concerning overwhelming community opposition to PBN routes, wherever they have been introduced over densely populated areas, around the world. No positive outcomes have been identified in these situations.

An example of the HCNF challenges can be accessed through the link below;


Whilst, as Heathrow point out, the UK Government may have signed up some years ago to PBN, it is now obvious that highly concentrated routes are completely unacceptable over high density populations like those around Heathrow.

It is negligent not to refer in the PEIR to the problems caused by the use of PBN, let alone to base Early Growth proposals on this technology.

This emphasises the unsuitability of Heathrow’s location for expansion, as the adverse impacts of aviation cannot be mitigated in such densely populated residential areas.

The extract below includes very recent evidence from US (which has pioneered PBN aka NextGen) set out in a US Government Audit Report. This notes that the introduction of these flight paths has fallen seriously behind programme in the face of community opposition, which has included legal action.

It is worth highlighting that the predicted financial benefits for introducing PBN in the US are only around a half of what was predicted at the time of their introduction. And the detrimental effects do not diminish with time.

This has led to questions being asked in the US concerning the role and performance of the FAA; the same questions should be asked about the CAA in the UK. Please see extract below from link;


A key feature of Heathrow’s consultation documentation is that it fails to indicate flight path strategies and in particular how Heathrow, the CAA and NATS have failed to find evidence of how the impacts can be mitigated, especially with PBN and given the extreme density of population around the airport. Heathrow on its own already accounts for circa 30% of aviation impacts across the whole of Europe, a truly shocking statistic.

Future operations – respite, night operations, runway alternation and directional preference

Respite assumptions have been used as a key building block of the case for expanding Heathrow, enabling as they do manipulation of average noise contours.

However, no health impact research has been undertaken into the practical effects of reducing respite over many communities from half to quarter of a day. In reality living conditions and perceptions of an area will be changed fundamentally by the proposed loss of respite.

Heathrow’s advisor on respite, Anderson Acoustics, has identified that circa 7-10dB LAmax reduction is required to achieve ‘valued respite’. However, the PEIR has failed entirely to show how sufficient separation can be achieved within Heathrow’s congested airspace between flight paths to create such levels of ‘valued respite’ over communities.

As seen the Teddington area, approximately 10-12 km from the airport, is currently impacted by four NPRs – and this is proposed to continue in a slightly different form according to Heathrow’s Design Envelopes – with potentially 67 planes an hour crossing the airspace using highly PBN concentrated flight paths. The reality (and as can be seen from Anderson’s reports) is that the noise from one flight path will spread over to others so very little relief will be available over significant areas of the neighbourhood, particularly having regard to the extreme high levels of noise created by overflights. Such considerations are totally ignored in the PEIR noise chapters.

Given that the ten ‘test case’ contour maps all show a significant increase in projected average noise levels over Teddington of around 3dBLAeq, even after assumptions concerning quieter planes and alternation, this is equivalent to more than doubling the numbers of overflights experienced in the area.

Whilst the alternation proposals propose two half day quiet periods out of each four days under easterly operations, there will be no easterly days without planes and given increasing commercial demand from airlines to fly to easterly and southern destinations (particularly at anti-social times of the day) there will be very little relief.

Against this background, what is especially important to note is that all test case maps (and noise modelling in the PEIR) are based on the assumption that western preference continues i.e. a ratio of 70:30 west to east operations. Notwithstanding this, the PEIR states that Heathrow would like to introduce ‘managed preference’.

Westerly preference was established to reduce the impact of louder departures (with full fuel loads and engines working at high thrusts) over high density areas in London. In our view these considerations still apply.

The PEIR itself contains no intelligible information concerning what would happen if managed preference were to change the established ratio, so the public who are being consulted have absolutely very little idea of the consequences if this proposal were to move forwards.

The map below is extracted from the PEIR Appendix 17.1.

Essentially the map is unreadable, impossible to tell the geographic locations, based on average metrics, assumptions concerning a quieter fleet and predicated on an assumption that public sensitivity will not increase in future. What this analysis fails to show is that on the basis of a 70/30 modal split Teddington would be overflown (very intensively) just over 22.5% of the time. If a 50/50 split applied this would increase to 37.5%, an increase of 67%. This would result in a complete change in the character of the area, in effect the destruction of the Teddington, Twickenham, Hampton and Molesey area as we know it. Very many people will be left with no alternative but to move out (assuming they can still sell their homes).

Given the scale of the much higher noise impact from departures when the area is overflown and the density of the populations to the east of the airport, it is imperative that the current western preference arrangements are maintained.

Future operations – ban on scheduled night flights

(a) Context

As already noted, the PEIR does not provide any N> metrics whereas these have been considered as key metrics for night-time disturbance for many years. For example, the WHO guidelines from 1999, which are still in force, suggest that ‘the intermittent character of noise has to be taken into account when setting night-time noise limits’;

Also as noted earlier the SoNA for night has been promised but remains long overdue;

Communities cannot help thinking that essential health impact information such as this (assuming it has been undertaken on an independent and impartial basis) is being held back because it could restrict aviation activity in the UK, notwithstanding the damage being caused to health under existing arrangements, which will become even worse under the PEIR proposals.

Government guidelines suggest that airspace changes should limit the impact on communities. The reality is that the present night-time impacts are NOT limited as 930k people are affected by on average 10 noise events of 60dB per night. For example, if a community were overflown 50% of the time this would be 20 events per night resulting in awakenings. This is already unacceptable and not in any sense ‘limited’. No increase in noise between 11-7am should be allowed. A limit should be set for the airport to reduce impacts to well below a few thousand people before any increase in night-time noise should be allowed.

Since 2006 night time noise impacts have increased while being subject to a quota count system – this will be addressed later in noise envelopes.

(b) Response on PEIR specific proposals

Despite being claimed as a major benefit arising from expansion, the proposals for late evening, night and early morning set out in the PEIR represent a significant worsening of conditions compared to current arrangements.

Presently areas under departures experience no scheduled overflights before 6.00am, when the planes are heard overhead approximately 15 minutes later. The consultation documents –  which are unclear but apparently propose a commencement of scheduled operations at 5.15am – should have given an explicit assurance that the start time for scheduled departures should remain at 6.00am (if not later).

The most disruptive period of the day however is late evening, when ambient noise is at its lowest, when people are trying to get to sleep but when Heathrow packs over 20 flights an hour to Far East, South American and African destinations. These long-distance planes are often the loudest of the day(see Explane screen shot earlier) and invariably overrun into the 30-minute Recovery Period or beyond. It is usual to experience 6 – 12 departures between 11.00 pm and midnight or beyond. These flights are extremely damaging to sleep patterns.

Under the expansion proposals the situation will be even worse. Heathrow proposes to move the latest scheduled departure from 10.50 to 11.00 pm, to increase allowable taxiing time from 10 to 20 minutes and to extend the Recovery Period to an hour up to midnight.

Given the planned 54% plus increase in ATMs this will have a devastating impact, being incompatible with family life and making the area unfit to live in for many. Flights at this time of day are recognised as a key ‘non acoustic’ factor increasing aviation’s significant impact on populations. These considerations are entirely absent from the DCO consultation material.

The net effect of the proposals set out in the PEIR regarding Night operations is that areas like Teddington could receive five hours respite or even less at night. This compares to World Health recommendations for 7-8 hours sleep for adults and 10-11 hours for children.

Having regard to this, the proposals set out in the PEIR are completely unacceptable. There should be a complete and absolute ban on night flights for 8 hours, such as is applicable for many airports around the world. Taxiing time and Recovery should be built into Heathrow’s scheduling so that complete respite at night is achieved.

Future operations – Early Growth

Early Growth was not considered by the Airports Commission nor included in the ANPS which was approved by Parliament.

The Early Growth proposals are regarded by communities as a serious encroachment on the environmental capacity limit of 480,000 flights per annuum agreed by Heathrow as part of a package of measures in relation to the development of Terminal 5.

Early Growth will be detrimental to health, especially sleep patterns, and quality of life. In particular, the concentration of arrivals between 6.00 and 7.00am, with up to 25 overflights permitted on each route during this time will have significant impact.

The noise analysis contained in the PEIR, showing no adverse impacts from Early Growth, is symptomatic of the inadequacy of the metrics and basis of assessmentused rather than addressing the effect of the proposals. This is a function of using deficient long-term average LAeq measures and not having regard (or even considering) widely acknowledged non-acoustic factors, such as flying at antisocial hours or putting communities under multiple flight paths.

For the first time many areas around the airport, such as Teddington, would be exposed to both arrivals and departures, potentially on a daily basis. Early Growth will entail many early departures and this will be followed throughout the day with up to 6 arrivals allowed per hour after 7.00 am. This would be extremely detrimental to respite relief afforded by operational mode.

No economic case, statement of need or other justification has been set out to support Early Growth and it is being put forward solely to gain commercial advantage for the airport. The need for flights before 7am is today highly questionable; flights from the Far East can now leave later from new 24hr/day operation airports e.g. Hong Kong, Bangkok, Singapore, similarly the Middle East airports operate 24hr/day all in low or no population situations. There is no justification for the same time zone such as Africa e.g. existing Cape Town to arrive at 4-5am when it can start latter in the evening from Cape Town. Similarly, America flights to LHR can leave latter to avoid arriving too early – as they are presently a daytime take off. For business meetings – if you want to get to Europe for a morning meeting flying through London does not make sense due to 1hr time difference and clearly early flights cannot be justified to arrive early for tourism. The last justification left to Heathrow seems to be that there may be advantages to freight arriving early but as Heathrow is one of the worst performing freight airports in Europe due to its long process times this seems a weak argument.

It should be noted that Early Growth is inextricably linked to the use of PBN, which has been the subject of a detailed critique earlier in this submission. The sharp turns associated with the proposed IPA design envelopes will generate additional noise impact, which has not been considered, let alone modelled in the PEIR.

Finally, although put forward only as a temporary measure, between 2022 and the opening of a third runway, this must be treated with great caution for two reasons. First, no information has been provided regarding future flight paths and it is conceivable Heathrow will seek to maintain these arrangements (without time limit) through an Airspace Change Process which is only to be decided after the DCO has been approved.

Secondly, there is considerable doubt as to whether a third runway will be able to proceed, either due a DCO application being refused on environmental or other grounds, or Heathrow being unable to fund the expansion package. In these circumstances the IPA proposals could become permanent and even extended as a substitute for a third runway (being far cheaper and lower risk).

The CAA’s CAP1819 document alludes to some of these possibilities in the context of Heathrow’s proposals in relation to abortive costs. These show a very considerable increase in planning and early development budgets, apparently explained by Heathrow’s increasing ‘maturity of understanding’ of the project. In this context CAP 1819 highlights the possibility of slippage to the expansion programme – to 2028 or even 2030.

On this basis Early Growth could last for a considerable period and, if the project runs into serious difficulty, the IPAs could become an alternative way for Heathrow to break the principle of the present environmental cap and expand its operations incrementally from the two-runway airport.

Compensation – Property and Compensation

The Parliamentary Transport Select Committee recommended in March 2018 that the thresholds that would apply to compensation and insulation should be reviewed prior to the ANPS being put before Parliament. The Secretary of State for Transport ignored this advice at that time but indicated these issues could be revisited at DCO stage.

With respect to purchase notices, in order to respect the established ‘polluter pays’ principle, the thresholds for entitlement need wholesale review. The deficiencies of SoNA 2014, on which Government policies are based have been referred to earlier in this submission – and the derisory compensation package (described by Heathrow and the previous Secretary of State as ‘world class’) – emanates from earlier noise policy thresholds.

The WHO ENG 2018 have exposed the non-conformity of current UK aviation noise policies with international standards. The WHO has identified (based on extensive international research) that 10% of people in Europe are ‘highly annoyed’ at 45 dB Lden (equivalent to 43 dB Laeq), whereas SoNA 2014 finds only 7-8% highly annoyed at 51 dBLAeq – which it also considers is the threshold for ‘lowest observable adverse effects’. These differences are fundamental and irreconcilable.

It is clear from this that for many (not only the most noise sensitive) annoyance begins far below the thresholds proposed by Heathrow for service of purchase notices. Whilst some people may be noise tolerant, many will feel compelled to move if they are able. It is inequitable that in these circumstances – and given the radical changes (including introduction of PBN) being promoted by Heathrow – that the innocent parties should bear the cost.

As an alternative proposal anyone newly impacted (say with an additional 1 dBLAeq representing 26% increase in overflight) or falling within the 51dB noise contour should be able to serve a blight notice on Heathrow at 100% of market value (assuming no diminution in value attributable to the scheme) with recovery of all removal costs including Stamp Duty.

Managing the effects of expansion – Noise Insulation

Similar principles apply as for purchase notice compensation; the thresholds for entitlement should be as stated above. The full cost of noise insulation (to an approved standard) should be paid to owners, having regard to the specific circumstances of the property. In the vast majority of cases this will exceed the £3,000 provision suggested by Heathrow, often by a very considerable amount. This will be especially relevant to larger properties or where conservation constraints requiring particular types of architectural treatment apply.

Managing the effects of expansion – Historic Environment

The PEIR assumes for the purposes of its noise impact analysis that there are no adverse impacts in relation to open spaces, notwithstanding that some of these are of National, Regional or, in the case of Kew Gardens of international importance. On this basis design envelopes, which will lead in time to flight paths, are being located and concentrated over open spaces, notwithstanding that these are very significant to public health and wellbeing.

In relation to the Teddington area these open spaces include Bushy Park, Hampton Court and Home Park and Richmond Park (which attracts 5 million visitors a year). These spaces are fundamental to the character and appeal of the area – and they are used for recreation by many people from a far wider catchment area. If they fall under intensively used concentrated PBN ‘noise sewers’ as is proposed, their appeal and utility will be lost at great cost to local and wider communities.

The PEIR ignores such considerations entirely, with absence of population assumptions that utilise these areas to conceal the real impacts of expansion. The loss of amenity within these key areas must be fully reflected in any cost benefit analysis put before the Planning Inspectorate in connection with the DCO.

General – growing within environmental limits

Base Line

The ANPS requires any expansion not to affect more people than ‘today’ using a 2013 baseline. The justification for expansion is based on economic growth which includes population growth. Heathrow argues that it has no control over population growth in the area it impacts and should therefore make the comparison at 2013 population levels. However, as the entire rationale for expansion is justified on growth associated with airport enlargement, population growth must be factored in.

The 2013 population study area is given as 6,002,800 and by 2035 it is 7,086,000. This is an 18% increase. Table 17.26 suggests a decrease in numbers affected at the LOAEL level between minus 11 to minus 22% depending on the scenario and sensitivity (on average 16% reduction), but accounting for population impacts this would suggest a very different picture with the range of outcomes now between an increase in those affected of plus 7% to a small decrease of 4%. Given the questionable assumptions on less noisy planes this presents a more challenging position and shows the need to strong environmental limits around noise and the noise envelope to protect communities.

The PEIR is suggesting that technological advances are shared between the communities and the industry. Disappointingly the PIER is only suggesting a 16% decrease in one of the noise metrics over a 22-year period, most of which will be offset by population growth (+18%), while it is suggesting a 50% increase in flight numbers – this is not sharing. As already pointed out noise event metrics are also related to noise annoyance and the PIER should be showing how these are decreased with time but no contours are being provided.

Sharing of technology advances should be established from 2013.

Approach to Evaluation

The PIER proposes an evaluation approach on primary factors and seems to suggest only evaluating secondary factors that may reduce adverse effects of primary factors (see comment in graphic below next to additional factors – from Table 17.9 Chapter 17 Noise and vibration). However, the secondary factors are crucial metrics that identify additional adverse effects and should be used to identify adverse effects in their own right. Event change metrics and single mode analysis will highlight significant adverse effects from the DCO project and must be considered even if primary factors are not showing adverse effects.

We do not accept the proposed change ratings which seem to show a lack of regard to the fact that aircraft noise is much more annoying than road noise as shown by many studies such as those shown by CAA’s review CAP 1588 Feb 2018. In all cases road annoyance is much lower than aircraft annoyance at the same average levels:

To present a aircraft change noise category and compare it to road as in Table 17.15 below is therefore unreasonable:

Loudness metrics such as LAmax are often confused with average sound energy levels metrics which use the same dB scale. Unlike a 1dB change in LAmax or loudness, which would be negligible, a 1dB change in LAeq is equivalent to 26% more planes of the same loudness. A 3dB change is equivalent to 100% increase in planes of the same loudness.  With this understanding for aircraft noise a low change would be <0.5dB (<12% change in events), a medium 1dB (25% change in events), high would be 2dB (~50% change in events) and very high would be 3dB and above (>100% change in events).

Ironically in Chapter 17 Annex D this point is confirmed where it states in the footnote 1 that ‘All else being equal, a 25% increase in number of movements would correspond to a 1dB increase in noise exposure.’

A secondary factor cannot be ‘used’ to claim a reduced effect from the impact of an increased primary factor, for example if average noise level has increased without any change in event numbers then this will increase annoyance for example planes become noisier by being heavier or lower but the same amount of events takes place – there would be no change in event numbers but annoyance has increased and the likely significant effect will NOT have been avoided, unlike what has been used in the description in table 2.3. As stated earlier secondary factors identify adverse effects not picked up by the deficiencies of using LAeq, which as we have pointed out there are many.

We would also challenge the proposed change categories linked to noise event changes; a low change would be <10%, a medium 10-20%, high would be 25% and above. Anything above 25% suggest significant adverse effects in its own right.

Total numbers impacted include winners and losers

The PEIR has identified numbers of people affected at different levels such as in table 2.1, annex H.

However, people who are adversely affected are much more sensitive as shown by many noise studies. For example, between the SOAEL to LOAEL band the PEIR (Table 2.3 Annex H) shows that between 537-780k are adversely affected this is between 47-68% of those present in the SOAEL to LOAEL band in 2013, these numbers will cause a massive outcry.

People outside the present LOAEL will also become more noise sensitive due to airspace change so many more people should be brought into the ‘new LOAEL’ after change.

There seems to be no systematic approach how to weight the impact of those adversely affected against those who may receive benefit and this needs to be integrated into the planning evaluation. It is not a simple numbers game. Those adversely effected should be given an increased weight. This would incentivise developers to avoid change, thereby creating the right behaviour by the industry.

One way to do this would be to reduce the assumed sensitivity threshold level for those experiencing increased impact from 51dB to 45dB (as 6dB is a change figure reported by WHO reviewers and would bring the UK LOAEL in line with WHO’s ‘highly annoyed level). This would result in much higher numbers being impacted as shown below. Given such massive impacts an agreed route forward should be agreed before the DCO. On the current basis of assessment policy aims would not be met.

Noise Envelope

The noise envelope must protect communities and relate to actual noise produced and the annoyance it creates. Protection of communities means reducing annoyance levels, so appropriate metrics have to be used and these will have to change with time as new information about annoyance levels becomes available. Noise envelopes should be based on numbers of people impacted and should reflect adverse change effects as well as non-acoustic factors such as time of day. Noise envelopes should incentivise the industry to work to reduce noise, they should be challenging to produce the right sharing behaviour.

As noted earlier the Heathrow night noise regime has been ‘managed’ by a quota count system, yet this has failed to decrease the night time noise impacts over the last 10 years. The area incurring N>20 60dB a night (on average) has increased by 17% and the population impacted has increased by 61%. These figures are published in Heathrow’s 2017 annual noise report undertaken by the CAA report CAP1801. This shows that a quota count approach does not control noise.

There are several reasons for this but examples include that fact that a wide bodied four engine A380 has an arrival QC count of 0.5 which is the same as a quieter 737-800. The A380 has a departure QC count of 2 whereas the 747-400 has a QC count of 4 but both planes produce practically the same noise profile on departure.

Planes can be flown in different ways; lower and noisier or higher and quieter. A QC system would not encourage best practice as it does not include the way a plane is flown.

Planes can be heavier if for example used on long haul flights with heavy fuel loads and so require engines to work at higher thrust on departures – the QC system does not take account of this.

In the future the QC system could fail even more as some 2nd generation planes are being given zero departure QC counts (e.g. A320 &A321neo 2nd Gen) so the QC system would not impose any restriction on these planes, yet they produce significant and annoying noise.

In summary a noise envelope must be based on real noise and metrics that actually correlate with annoyance.

In addition to 54 & 51dB LAeq levels, which are obvious requirements, to protect populations further out a level below 51dB LAeq should be used as 50% of those Highly Annoyed are below this level (let alone those moderately annoyed). The calculation for 50% annoyed below the 51dB level is shown below:

Recent work is showing that best correlation with annoyance uses both LAeq and N> metrics (presentation by Rainer Guski at Heathrow Noise Annoyance workshop 14th August 2019). The noise envelope should therefore set limits on LAeq and N> metrics. These should be in single mode and be location or flight path based.

SoNA has shown similar annoyance between 51dB LAeq and ~25 N>65 events in a day. A noise envelope should therefore be based around the lower of 25 N>65dB events or 51dB LAeq. A night envelope should be established for N>60dB in 8hrs once SoNA night is published.         

In addition, the noise envelopes should reflect the additional impacts caused by early morning and late evening ‘shoulder periods’ – a factor reflected in the key EU Lden measure.

Each year a projection should be made to confirm noise conditions are being satisfied with any planned increase in flight numbers.

Every 5 years a review of the noise annoyance survey should be undertaken to show that the noise envelope is considering the correct metric levels for annoyance at the time. This would reflect growing public sensitivity over time. If changes occur the noise envelope would have to be adjusted to the new (most likely lower) thresholds for annoyance. This will place an emphasis on the developer to deliver the correct mitigation measures claimed to reduce noise annoyance such as ‘valued respite’.

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  1. S. Eiberle
    4th October 2019

    Thank you so much for all your hard and thorough work on the behalf of so many people who will be affected should the expansion go ahead.

  2. Dr Gerald Morgan, FTCD
    3rd October 2019

    Many thanks for this excellent and detailed report, Gerald Morgan (leader: English Parliamentary Party, 2001)

  3. 2nd October 2019

    Dear Dave, Stephen and Neil – WOW! Thank you for using the term ‘less noisy’ and not LHR’s euphemistic ‘quieter’. A little anxious, as a SE Londoner, to see wish to retain Westerly preference; we would love a 50/50 split over the current 70/30 but respect the fact that you are closer to LHR than we are in Camberwell SE5 where departures (at the moment) do not have an impact. We do, however, suffer from 19 hours arrivals overflight to LHR (4.30am – 11/11.30pm) at 60dB+ the rule, with LCY flying lower increasingly in the mix. None of the current scenarios any of us suffers is acceptable and it is good to be working together to challenge the status quo and assumptions made by decision makers using inadequate or no true information.

  4. Mrs Jessop
    2nd October 2019

    You guys are amazing. Thanks for doing such great work. Do you think there will be a legal challenge to the latest consultation, given it was not fit for purpose?

    • 2nd October 2019

      Thanks very much for your comment. Difficult to say whether there will be another Judicial Review. There is an appeal against the existing High Court judgment, which will be heard from the 17th October and last for about a week. If there were another JR, it would probably be of any Development Consent Order if and when that were made (it is quite possible that a Development Consent Order will be refused because of say a number of environmental reasons). It is also possible that a subsequent government will suspend the Airports National Policy Statement, which it is entitled to do if it is of the view that circumstances have changed

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