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Notes from on-camera remarks at the City of Folsom’s 5/14/2013 City Council meeting, r egarding air carrier cargo approa

Notes from on-camera remarks at the City of Folsom’s 5/14/2013 City Council meeting, r egarding air carrier cargo approaches and noise. Prepared in July, 2013 by Paul Raveling, resident of El Dorado Hills and possibly the only person in the EDH/Folsom area who has:.

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Notes from on-camera remarks at the City of Folsom’s 5/14/2013 City Council meeting, r egarding air carrier cargo approa

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  1. Notes from on-camera remarks at the City of Folsom’s 5/14/2013 City Council meeting, regarding air carrier cargo approaches and noise Prepared in July, 2013 by Paul Raveling, resident of El Dorado Hills and possibly the only person in the EDH/Folsom area who has: • Actually measured overflight noise and observed approaches • Carefully researched actual flight tracks and operating practices Summary: The City of Folsom referred to “a pile of crap” from the Sacramento County Airport System, But the metaphoric manure spreader belongs to the City of Folsom. For contact by email: Paul.Raveling@sierrafoot.org

  2. Approaches as portrayed by the City of Folsom: At rooftop level, up to hundreds of approaches all night long, pilots “Jammin’ their engines full speed”,super-loud & “rattling rooftops” Photo: A300-600 freighter, photographed off end of Mather Runway 22L, camera lens zoomed to 200 mm. Actual Approaches over EDH & Folsom: On ILS glide slope, over Ridgeview at ~3,755 ft MSL, 2,610 AGL, one (1)overflight of EDH/Folsom per night, throttles slightly above flight idle.Typical measurednoise is 66 to 68 dBA. Photo: A300-600 over Ridgeview in EDH, Camera lens at 55 mm to match human visual field of view

  3. Who has best first-hand knowledge? Consider home locations… Red dots: 8 Chronic complainers Yellow dot: 1 Community leader with past belief in a set of false claims Green dots: 8 Homeowners -- When asked, all said there’s no noise problem CAMRR Mather 22L approach LDOOR Ridgeview site, four homes at point of maximum noise exposure in EDH YOSHE

  4. Range usually claimed by complainers Mode = 64.5 dBA Mean = 65.9 dBA Median = 66.4 dBA Minimum = 58.0 dBA Maximum = 72.9 dBA 99.1 dBA, Actual rock-band noise measured at opening Of Folsom Lake Crossing 87.5 dBA, Actual noise of A300 Landing measured at end of runway

  5. Another view: Given 67 dBA actual noise at Ridgeview, mathematically derived* equivalent noise levelsat frequent complainers’ homes are at most at these levels… Red bars: Number of complainer home locations in each noise-level, With 2-dBA graphic resolution Claim from complainers in El Dorado County: 80 to 90 dBA 72.9 dBA, Maximum of 2008 measurements at Ridgeview site 67 dBA, Reference level:Median of measurements at Ridgeview site, El Dorado Hills 54 dBA, T.M. in El Dorado Hills 52 dBA, C.C. in Folsom 51 dBA, D.C. in Folsom 48dBA, G.O.in Folsom 44dBA, M.B. in El Dorado Hills 42dBA, H.F. in Folsom 36dBA, W.B. in Folsom 24dBA, J.K. in Shingle Springs *Correction for spatial dispersion: L2 = L1 – 20 log( S2 / S1 ) L1 & L2 refer to sound levels in dBAS1 & S2 refer to slant distance from ground site to aircraft

  6. Actual Noise Levels: Measured in EDH Mathematically derived for homesof chronic complainersin Folsom, EDH, & Shingle Springs Depicted as annotations on an graphic originally from URS Corporation This is the complete image. 67 dBA is the median (typical) noiselevel measured at the EDH locationwith maximum noise exposure. Numbers cited for complainers’ homes aremaxima, actual sound livels are lower. The maxima are for no energy loss in propagation of acoustic waves through air: Lmax(site) = Lmax(ref ) – 20 * log( S(site) / S(ref) ) Where S refers to slant distance.

  7. Actual Noise Levels, a closer view

  8. Ridgeview Overflight Altitude Distributionfrom flight track samples taken in 2008; altitudes MSL

  9. Rate of EDH/Folsom arrival overflightsin early morning (“oh dark thirty”) hourson UPS “busiest” days at Mather

  10. Rate of EDH/Folsom arrival overflights“every other minute” “all night long” A Folsom resident claimed on camera “one every other minute” “all night long” 180 Two (2) per night, 11 ½ hours apart

  11. Issues stated on-camera, 5/14/2013 • Frequency of approaches over homes: Statement by a citizen, Mr. Bryant • Approaches at low altitudes: Statements by Mr. Starsky and Mr. Miklos • High (maximum) throttle setting: Statement by Mr. Starsky • Credibility of Sacramento County Airport System projections:Statement by Mr. Starsky • KCRA report: City of Folsom threatens to sue if noise cannot be reduced;original statement assumed to be by the City of Folsom • KCRA report: Mather runway expansion is planned to allow increased cargo traffic;original statement assumed to be by the City of Folsom Ratings of these statements in this document use the politifact.com classifications:True, Mostly True, Half True, Mostly False, False, and Pants on Fire. Discussion of the final two items is omitted for brevity.

  12. Frequency of night approaches over homes Mr. Bryant (citizen): [lives on Landrum Circle: 2.25 miles from the ILS approach]: “It was constant, every couple of minutes you would have a plane come induring the night.” Fact check rating, ~ 1 approach per 2 minutes throughout night: Pants on Fire (same sense as used by politifact.com) At present there is a maximum of one (1) air carrier cargo overflight per night In hours after midnight. Until route changes were made in 2012 there were two (2)per night. If the preceding day’s evening arrival is counted as a night flight, there are two (2) night overflights, separated by approximately 11 ½ hours. If the claim is meant to cover 12 hours (“half the day is night”), Mr. Bryant’s statementcorresponds to 360 arrivals over Folsom per night. If it is meant to cover 6 hours,such as midnight to 6 a.m., it corresponds to 180 arrivals over Folsom per night. The discrepancy is 358 nightly operations for the 12-hour case, 179 for the 6-hour case.

  13. Altitude on Approach Mr. Starsky: “These guys come in, rooftop level, jammin’ their engines on full speed.” Fact check rating, rooftop level: Pants on Fire (same sense as used by politifact.com) Almost all overflights of Folsom are on the ILS glide slope to Mather Runway 22L, altitude deviation usually is less than 100 feet. Overflights at rooftop level NEVER occur.Actual Folsom overflight altitudes are: The easternmost residences (two) are on Hildebrand Circle, between Ritchie Street and Hana Way, ~420 feet east of Empire Ranch Road. The westernmost residence is at or near 161 Pinder Court, ~280 feet north of Iron Point Road.

  14. Altitude on Approach Mr. Miklos: “We have at, you know, oh dark thirty, coming over at 3,000 feet, 2,000 feet; basically it’s the same pattern, they rattle rooftops.” Fact check rating, approach altitude 3,000 – 2,000 feet: Mostly False: Imbalanced toward more wrongthan right; quantitatively biased The actual altitude range is from 3,750 feet MSL to 2,840 feet MSL (east to west). Altitude above ground level (AGL) also depends on terrain: 3,020 feet AGL to 2,510 feet AGL. If “3,000 to 2,000” was intended to describe the glide slope, east-to-west in the critical area: -- If referring to MSL, it’s numerically incorrect: Actual is 3,750 - 2,840. -- If referring to AGL, it’s also incorrect but much closer: Actual is 3,020 – 2,510. If “3,000 to 2,000” was intended to refer to a horizontal band in the critical area: -- If referring to MSL, 16% of the cited range overlaps the actual range of altitudes. It omits 82% of the actual range, with the omission entirely above the cited range. -- If referring to AGL, 49% of the cited range overlaps the actual range of altitudes. It omits only 4% of the actual range.

  15. Throttle Setting (=> Engine Noise) Mr. Starsky: “These guys come in, rooftop level, jammin’ their engines on full speed.” Fact check rating, throttle setting: Pants on Fire (same sense as used by politifact.com) Actual throttle setting is at flight idle or slightly above for freightersglide slope over EDH and Folsom. This can be confirmed in three ways: (1) Researching records of flight paths which include altitude data; (2) Asking Air Transport Pilots who fly such airliners or cargo aircraft; (3) Inferring this by reasonably simple mathematical analysis. Part of the math is basic physics: An aircraft’s total energy is the sum of its potential energy(proportional to altitude) and kinetic energy (proportional to the square of speed). Until final approach, aircraft must decrease both speed and altitude, additively decreasing total energy. Flying at full throttle doesthe opposite, increasing total energy.Another significant relation is that in gliding flight (at zero thrust) the glide ratio is equal to the aircraft’s aerodynamic lift-to-drag ratio (L/D). This determines the glide slope angle, the arc tangent of the reciprocalof L/D. For air carrier cargo aircraft over Folsom and EDH, that glide slope is very slightly steeper than thestandard 3.0-degree ILS glide slope while the aircraft is in a low-drag configuration.

  16. Useful Resources for data collectionpartial list, page 1 All web-based tools listed below except WebTrak have corresponding apps for iPads and/or iPhones. • Personal observations and measurements. Photographic recording can facilitate recording, partly by means of EXIF data.I used this in part to record SPL (Sound Pressure Level) meter readings, using ameter with calibration certified to plus or minus 1.5 dBA. • WebTrak, http://webtrak.bksv.com/smf -- Replays recorded flight tracksfrom data originally recorded by Air Traffic Control. • FlightAware, http://www.flightaware.com -- Records history of recent operationsand scheduled operations not yet completed; also displays flight tracks. • AirNav, http:www.airnav.com/airport/KMHR -- Official airport information includespulished IFR Approach plates and statistics on annual rates of operations

  17. Useful Resources for data collectionpartial list, page 2 All web-based tools listed below have corresponding apps for iPads and/or iPhones. • Live data-feed tools which facilitate direct personal observation of overflights:Flightradar24, http://www.flightradar24.com/Defaults to viewing live traffic in a simulated radar display.The web client (with awkward user interface) also has a replay mode, iPad/iPhone don’t. The web client’s user interface is more awkward than the iPad/iPhone apps.LiveATC.net, http://www.liveatc.net/flisten.php?mount=kmhr_norcal&icao=kmhr This URL selects a live ATC radio feed selects NORCAL Approach Control, Expo sector. UPS arrivals from the east and from Reno are via Expo sector. • Google Earth, http://www.earth.google.comEspecially with graphic annotations to illustrate the standard approach route(s).On windows, Google Earth reports ground elevations. Using appropriate .kml files,it can be used to illustrate at least the standard approach path in three dimensions,and to measurehorizontal distances from observers’ locations to the approach path.At the date of this writing ground elevations are not available on the corresponding iPad& iPhone apps. “.kml” files on sierrafoot.org are being updated to reflect changesmade by the FAA in September 2012 to Mather ILS approaches.

  18. Useful Resources for data collectionpartial list, page 3 These resources are web-only, no iPad or iPhone apps. • Sacramento County Airport System web site, http://www.sacramento.aero/scas/This site includes definitive documents and data. Access via Google earth site searches(Site:www.sacramento.aero/scas/) are frequently the quickest way to locatespecific information.For best browsing, these sections are recommended:-- Mather Airport (MHR):http://www.sacramento.aero/mhr/Also, MHR tab under “Our Airports” on SCAS home page-- Environmental / Noise, with detail subsections for Mather:http://www.sacramento.aero/scas/environment/noise/mather_airport_mhr/Noise-related documents and links to data

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