Noise or Annoyance?

Is actual jet noise a problem?Or is the problem only present in

complaints?

Public discourse and public policydetermine public perception.

If public agencies treat something as a problem, the public perceives it as a public problem, even if it is not.

Why this is important to APAC:

Approaches as portrayed by vocal critics:

A300-600 freighter, photographedoff end of Runway 22L,camera lens zoomed to 200 mm.

Actual Approachesover EDH:

A300-600 freighter, photographedfrom Ridgeview, at the point of minimumaltitude above ground level in EDH

Camera lens at 55 mm, matchingperspective of human vision

Fundamentaltypes of issues:

Objective factors-- Shared by everyone

Subjective factors: Annoyance-- Generally not shared by everyone

Objective Factors Regulatory: CNEL noise (Community Noise Equivalent Level),

required by state to be no more than 65 dB CNEL

Single event noise: SEL, Lmax:This depends mainly on aircraft altitude and descent rate:On a standard 3-degree glide slope throttle setting isapproximately at flight idle.

Number of EDH overflights per day:

Four (4) overflights are typical in May, 2013on cargo-busy days of the week.

Major Subjective Factors Personal factors Social factors Subjective perceptions of objective factors

All of these combine to produce Annoyance. A large body of research has shown that personal and social factors often are totally unrelated to objective factors.

At least half a century ago researchers began developing and using metrics to associate actual measures of noise with observable measures of annoyance, including complaint rates for jet noise. These slides use one such measure, the NNI index.

Sanity Checks:

How does our situation compare withsomewhat similar ones elsewhere?

• Objective factors• Subjective factors: Annoyance

Locations of publicly vocal complainers

Homeowners reportingno jet noise problem

From personal contact while measuringactual noise levels

4 of 4 homeowners contacted at point ofMaximum noise in El Dorado Hills

2 of 2 +

+

+

+

++

Highly vocal critics claiming noise problems:Distance from home to approach path

Critic Address Locality Distance, miles

G.O. 428 Williams St Folsom 1.22

C.C. 104 Kilcairn Way Folsom 0.95

W.B. 108 Landrum Circle Folsom 2.27

T.M. 2621 Aberdeen Ln El Dorado Hills 0.65

M.B. 6160 Edgehill Dr El Dorado Hills 1.36

J.K. 3951 Welker Ln Shingle Springs 4.09

Significant less-vocal critic: Chair/co-chair of EDH APAC

N.R. 1357 Lakehills Dr El Dorado Hills 3.57

This data is retained from an earlier year, Individual critics may have moved.In most locations of El Dorado Hills approach noise cannot be discerned fromambient background noise it distances of about 1¼ miles plus or minus ¼ mile.

Gold Line: Mather 22L ILS course

Red Line: 4.09 miles, shortest distance fromhome of serial complainer in Shingle Springsto Mather 22L ILS course

Yellow shading: Approximate area in whichan approch can be barely audibledepending on conditions.

Red shading: Aproximate area in which an air carriercargo aircraft approach generally is audible, thoughsometimes is inaudible at the edges.2.0 miles wide, 1.0 mile either side of center.

Typical UPS arrival via Hangtown VOR,Turning onto Mather 22L ILS course at CAMRR

Minimum separation of approachfrom home of serial complainer in Shingle Springs

is 4.09 miles.

Home of serial complainer

Specific claims & measured reality Claim: A serial complainer in Shingle springs says he routinely experiences

noise of 80 – 90 dB at his home.

Fact: His home is 4.09 miles from the nearest point on the standardapproach paths currently in use. Approach noise from these aircraftdrops below the limit of human perception at a slant distance ofabout 1.5 miles.

An example was a Board Of Supervisors Town Hall meeting in 2007at the EDH Senior Center. This is 1.2 miles from the nearest point beneaththe ILS approach to Mather Runway 22L. A 757-200 freighter passed byabout 5 minutes before the meeting started; no one noticed the freighterexcept me. I noticed because I saw it while parking my convertiblewith the top down.

Specific claims & measured reality Claim: A serial complainer in Shingle springs says he routinely experiences

noise of 80 – 90 dB at his home. [repeated to consider sound levels]

Fact: The loudest noise level occurs directly beneath the aircraftat its minimum crossing altitude above ground level. In El Dorado Countythis is at a particular location on Ridgeview in El Dorado Hills.

Fact: Typical measured maximum instantaneous noise levels (Lmax)beneath aircraft crossing Ridgeview in EDH are in the range of 66 to 68 dBA.This is a level usually associated with quiet conversation at 3 feet.It is also the typical level in Board of Supervisors meetings.

Fact: The loudest approach I have ever measured in El Dorado Countyproduced a maximum of 74 dBA at Ridgeview.

Fact: The loudest approach noise I’ve measured anywhere was 84 dBA.Multiple measurements showed this for 747-400 airliners on approach to SFO, about 1,800 feet above ground level at Foster City. SFO normally has a far lowerrate of complaints than is produced by our area’s serial complainers.

Sanity Checks:

How does our situation compare withsomewhat similar ones elsewhere?

• Objective factors• Subjective factors: Annoyance

Questions…

• What sound levels do freighter approaches actually produce on the ground?

• How much traffic (approaches per day over EDH/Folsom) is there? When?

• How will these measures change in the future?

• How do complaints about noise relate to actual noise?• What misconceptions are evident in complaints?• How do public agencies affect public perception?

For major objective factors:

Not for navigation[Not a current IFR chart]

Mather ILS vertical profile

Not for navigation[Not a current IFR chart]

CAMRR 6,500

LDORR 5,000

YOSHE 3,000 Nominal

ILS Approach

EDH West Ridge3,900

EDH East Ridge4,600

NominalILS Approach

ILS intercept @ LDORR

Plus a burst of afternoon traffic

VFR approachSouth of US 50

Loudest 2008 freighter approachrecorded in WebTrak:

Probably about 85 dBA

Approach from southBy UPS954 plus otherTraffic (week before Christmas)

Approach Usage

Data for the week of December 15 through December 22, 2008-- The week before Christmas, busiest freight week of the year

Types of Approach

ILSVFR from southVFR from westVFR from northVFR from eastOther

Approach Noise Exposure Potential

Data for the week of December 15 through December 22, 2008-- The week before Christmas, busiest freight week of the year

EDH/Folsom Overflight Exposure

No overflightOverflight in af-ternoon/eveningOverflight in early morning

Overflight Noise MeasurementMeasurements on SierraFoot.org use Lmax, the maximum noise level

SEL/SENEL – Oakland, Foster City

Lmax, Oakland, Foster City

SEL/SENEL, EDH West Ridge

Lmax, EDH West Ridge

Actual Crossing Altitudes on ILSat Initial Approach Fix

Rescue area, north of Shingle Springs

Actual Crossing Altitudes on ILSat El Dorado Hills west ridge

For comparison: SFO approach at Foster City

For comparison: SFO approach at Foster City

Measured Noise

Mininum Lmax Average Lmax Maximum Lmax

0

10

20

30

40

50

60

70

80

90

EDH CSDEDH West RidgeFoster City

Measured Noise

Approaches per day NNI

050

100150200250300350400

EDH CSD

EDH West Ridge

Foster CityEDH CSDEDH West RidgeFoster City

Approaches per dayand Noise-Number Index

for Annoyance

NNI Annoyance & Complaint RateEDH CSD EDH West Ridge Foster City

NNI – Noise/Number Index

7.3 11.7 46.2

Complaintsper 1,000 approaches

1,919 2.2

NNI is the first widely accepted index of annoyance due to exposure to jet noise, adopted by the British more than 40 years ago. Published literature, includingdocuments cited by www.keepthepeace.org, indicate that NNI less than 35corresponds to insufficient annoyance to produce complaints. Values somewhatabove, such as Foster City‘s 46.2, are expected to produce sporadic complaints.

This table reports a composite complaint rate for Mather-correlated complaints fromFolsom, El Dorado Hills, Rescue, and Shingle Springs. All complaint countsare from the first 7 months of 2008.

Can a single serial complainer dominate complaint statistics?

Yes -- Here’s an example from LAX, July 2008:

Serial Complainers & MHRNoise complaint statistics correlated with Mather flights also showhighly disparate rates depending on the location of complainers.

2008 total complaints for Mather noise

Folsom + EDH + RSS*: 7,448 complaints

Near Mather: 22 complaints

Everywhere else: 146 complaints

* RSS: Rescue & Shingle Springs

Average monthly complaints : 45 per Folsom caller, 12 per EDH caller

Serial Complainers & SMF

2008 total complaints for Sac International noise

Folsom + EDH + Shingle Springs: 2,461 com-plaints

Everywhere else: 191 complaints

Location-specific complaints also apply to noise attributed to flightsto and from Sacramento International Airport.

Average monthly complaints: 33 per Folsom caller, 8 per EDH caller

MHR serial complaints by community

All from Folsom, EDH, Rescue & Shingle Springs

Folsom: 6,024El Dorado Hills: 1,686Rescue & Shingle Springs: 155

Complaint percentage distribution for SMF is similar, ± 6% per community

SMF serial complaints by community

All from Folsom, EDH, Rescue & Shingle Springs

Folsom: 1,579El Dorado Hills: 622Rescue & Shingle Springs: 34

Complaint percentage distribution for MHR is similar, ± 6% per community

Populace in general

Most people in the EDH/Folsom area think we have problems with jets flying too low and too loud. The main exceptions are those who live directly under the ILS approach, who generally indicate no problem exists.

The public understanding derives mainly from public dialog and media news coverage. Public agency treatment of the issue as a noise problem has carried strong influence – especially in connection with the City of Folsom‘s 2007 law suit.

Random sample:Noise under the ILS, west ridge, EDH – loudest point for Mather

approaches

Afternoon of August 25, 2009

UPS 2958

USAF T-38

Ford F250

UPS 2960

0 10 20 30 40 50 60 70 80

Noise: Lmax

Noise: Lmax

Remaining slides are excerpts from a typical sessionof observing a freighter approach and measuring itsnoise level from Ridgeview, directly under the approach.

First, a web tool (FlyteComm in this case) is used to identify air carrier cargo flightsscheduled and en route to Mather. The screen image shown is for a flight UPS 2958,which did not overfly EDH on this day. A different web tool, WebTrak, was used later to check the UPS 2958 actual flight trackin the Sacramento region. After driving to 3270 Ridgeview Dr, directly below the ILS approach to Runway 22L,while waiting a T-38 and a pickup truck were photographed and their noise measured.

UPS 2960, a 757-200, was photographed as it flew over on the ILS approach.

The sound level meter reading was photographed after it had latched the maximumsound (pressure) level of 61.7 dBA, roughly half as loud as the T-38 and the pickup truck.

VFR Approach: 0 dBA in “sensitive area”

Sample measurement

The following sequence of slides shows an exampleof noise data collection. The aircraft is photographedas it passes, then the noise meter is photographedto record the noise meter’s Lmax reading. Not visible,the camera records date and time.

This sample shows a low-noise approach over Ridgeview.Most approaches are in the range of 66 dBA to 68 dBA.

UPS 2960 (757-200F): 61.7 dBA

The next two slides show two examples of loudernon-cargo noise sources which have not beenthe subject of public complaints.

Both produced noise levels which human hearingperceives as about twice as loud as the precedinglow-noise approach. They would be perceived as significantly louderthan typical cargo approaches, not fully twice as loud.

USAF T-38 at 3,000 ft: 72.8 dBA

Ford F250: 75.3 dBA

The End…… with the lens zoomedto 200 mm telephoto