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Noise or Annoyance?. Is actual jet noise a problem? Or is the problem only present in complaints?. Approaches as portrayed by critics…. Approaches as portrayed by critics…. A300-600 freighter, photographed off end of Runway 22L, camera lens zoomed to 300 mm. Actual Approach over EDH.
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Noise or Annoyance? Is actual jet noise a problem? Or is the problem only present in complaints?
Approaches as portrayed by critics… A300-600 freighter, photographed off end of Runway 22L, camera lens zoomed to 300 mm Actual Approach over EDH A300-600 freighter, photographed from Ridgeview at point of minimum altitude above ground level in EDH Camera lens at 55 mm, matchingperspective of human vision
Sanity Checks: How does our situation compare with somewhat similar ones elsewhere? • Objective factors • Subjective factors
Homeowners reportingno jet noise problem From personal contact while measuring actual noise levels 2 of 2 4 of 4 homeowners contacted at point of Maximum noise in El Dorado Hills
Interwoven Issues • 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?
CAMRR 6,500 LDORR 5,000 YOSHE 3,000 Nominal ILS Approach
Nominal ILS Approach EDH East Ridge 4,600 EDH West Ridge 3,900
ILS intercept @ LDORR Plus a burst of afternoon traffic
VFR approach South of US 50
Loudest 2008 freighter approach recorded in WebTrak: Probably about 85 dBA
Approach from south By UPS954 plus other Traffic (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
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
OverflightNoise Measurement Measurements 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 FixRescue area, north of Shingle Springs
Actual Crossing Altitudes on ILSat El Dorado Hills west ridge
NNI Annoyance & Complaint Rate 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, including documents cited by www.keepthepeace.org, indicate that NNI less than 35 corresponds to insufficient annoyance to produce complaints. Values somewhat above, such as Foster City‘s 46.2, are expected to produce sporadic complaints. This table reports a composite complaint rate for Mather-correlated complaints from Folsom, El Dorado Hills, Rescue, and Shingle Springs. All complaint counts are 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 & MHR Noise complaint statistics correlated with Mather flights also show highly disparate rates depending on the location of complainers. Average monthly complaints : 45 per Folsom caller, 12 per EDH caller
Serial Complainers & SMF Location-specific complaints also apply to noise attributed to flights to and from Sacramento International Airport. Average monthly complaints: 33 per Folsom caller, 8 per EDH caller
MHR serial complaints by community Complaint percentage distribution for SMF is similar, ± 6% per community
SMF serial complaints by community 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.
Public discourse and public policydetermine public perception.If public agencies treat something as a problem the public perceives it as a problem.
Random sample:Noise under the ILS, west ridge, EDH – loudest point for Mather approaches Afternoon of August 25, 2009
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.
UPS 2958 from Louisville: 0 dBA Inaudible from west ridge: Flew VFR approach south of US 50,shortcutting ILS as direct routing from enroute clearance.
The End… … with the lens zoomedto 300 mm telephoto
