Supplementary Noise

Contour Maps

Chris BennettStop Stansted Expansion

 

Background

• EA omits several noise contour maps requested by UDC Scoping Opinion and/or recommended by SSE

• Amongst others:– 50 dBA Leq 16 hour daytime contours– separate contours for all easterly and all westerly

days– N65/N70 contours (showing number of events above

a particular level)

Caveats

• Even the additional (“Australian”) metrics don’t cover all the problem areas

• Noise doesn’t stop at the contour edge • Averaging effects• INM vs ANCON• Below 54/57 dBA Leq, the parameters for

input data become a problem• Access to data

– Apparent contradictions in ES tables– Clarifications not available

35 mppa 50 & 57 Leq compared

Modal split: 35 mppa R05 (easterly)

Modal split: 35 mppa R05 – easterly (pink) + normal 57 Leq ie all ops (grey)

Modal split: 35 mppa R23 (westerly)

Modal split: 35 mppa R23 – westerly (pink) + normal 57 Leq ie all ops (grey)

What do 65 or 70 decibels mean to the listener?

One location’s LAMax (from the ES; red annotations by SSE)

35 mppa: Events above 70 decibels (16 hour summer day)

G008

35 mppa: Events above 70 decibels (16 hour summer day) + 57 dBA Leq

G008

35 mppa: Events above 65 decibels (16 hour summer day)

G008

35 mppa: Events above 65 decibels (16 hour summer day) + 57 dBA Leq

G008

Conclusion

• Australian additional metrics provide a more intuitive illustration of likely noise effects

• Modal split contour maps show the effects on days when an area is actually being overflown

• Both help to unscramble the averaging effects of Leq maps and allow people to judge for themselves

• Both should be provided by BAA as part of the ES, together with a clear listing of the input data and assumed parameters for each map

Potential R1 Capacity and Significance – Particularly for

Surface Access

Brian RossStop Stansted Expansion

0

5

10

15

20

25

30

35

40

45

50

1995 2000 2005 2014 2014 2021 2030

Stansted R1: Potential Expansion to 2030 (mppa)

= Actual

= BAA Projection

= SSE Projections (capacity of R1)

49.7

44.6

39.8

35.0

22.0

11.9

3.9

• BAA is asking for unlimited MPPA subject to 243,000 PATMs

• BAA forecasting track record is historically poor - consistently underestimating growth – 2001 planning application forecast 23mppa by 2010/11 (with long haul accounting for 17%)

• SSE modelling shows 243,000 PATMs provides realistic potential

for about 40mppa by 2014, 45mppa by 2021 (12.4% long haul)

and 50mppa by 2030 (16.6% long haul)

• Average number of passengers per aircraft is key issue: depends

on average aircraft size and load factor

• Average aircraft size is steadily increasing (at all major airports)

and focus on long haul would add impetus to this at Stansted (Note

that SH&E also considered BAA long haul forecasts were too low)

• BAA uses 81% load factor for base case but 79% for 35mppa and

only 77% for sensitivity. In 2005 Ryanair achieved 83% and Easyjet 85%. (Note that SH&E did not look at load factors)

BAA seeks to minimise impact of 243,000 PATMs

BAA seeks to minimise impact of 243,000 PATMs

(cont’d)• BAA assumption of only 5% increase in passengers per PATM by

2014 lacks credibility:- Stansted has seen 97% increase over past 10

years- Heathrow is forecasting 25% increase and Gatwick

15%

• Even more significant is absence of BAA forecast beyond 2014 –

when regional planning horizon is 2021 and ATWP is 2030

• Heathrow expects >180 passengers per PATM by 2014

• Airports in Japan already achieving >200 passengers per PATM

• Is it unrealistic to consider that Stansted might match this 15

years from now (2021)? 24 years from now (2030)?

• Ryanair and Easyjet aircraft types may be unlikely to change significantly by 2014 – but by 2021? – 2030?

60

80

100

120

140

160

180

< - - - - - BAA Forecast to 2014 - - - - ->

Passengers per PATM

Heathrow

Gatwick

Stansted

+25%

+15%

+5%

<- - - - - - - - Actual 1995-2005 - - - - - - - - >

+13%

+14%

+97%

• Passenger throughput AND characteristics are fundamental in assessing surface access impact and need for new infrastructure

• BAA has sought to maximise surface access demand in 2014 base case and minimise 2014 projections for current planning application

• BAA changes to passenger origin/destination profile are unexplained and counterintuitive – seem contrived to reduce rail implications

• BAA forecasts that transfer passengers reduce from 12.5% currentto 10.0% at 25mppa and then increase to 16.6% for 35mppa – i.e. increasing base case surface access demand and reducing surface access demand for 35mppa scenario – again, narrowing the gap

• SH&E identified above two points but did not address their significance re surface access

• However, BAA uses its flawed analysis to argue that its proposal would only result in 10%-11% more peak traffic in 2014 and to claim (e.g.)

“The increased flows associated with the 35 mppa (enhanced) case

case and the 40 mppa sensitivity test would not seriously exacerbate conditions likely to prevail with 25 mppa.”

Surface access implications are highly significant

• BAA forecast for 35mppa (or max 40mppa) by 2014 is unreliableand understates impacts

• What happens beyond 2014 – especially if R2 does not proceed

• All other impacts are derived from BAA core forecasts – and are similarly unreliable

• Surface access is a key example. There could be an additional 25mppa not 10-15mppa.

• In addition, BAA assumptions on transfer passengers and origin/ destination appear to have been deliberately contrived to minimise its stated surface access implications

• And even without reworking the surface access implications to reflect the very substantial under-projections, BAA acknowledges that congestion problems will arise

Concluding points