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Home My WebLink AboutRPT 3 AIRPORT STATUS 01-17-94// REPORTS NO. 3 1-17-94 DATE: JANUARY 17, 1994 Inter-Corn TO: WILLIAM /%. HUSTON, CITY MAN/%GER FROM: COMMUNITY DEVELOPMENT DEP/%RTMENT SUBJECT: /%IRPORT ST/%TUS REPORT RECOMMENDATION Receive and file. FISCAL IMPACT The City retains the consulting firm of J. J. Van Houten and Associates, Inc. for review of noise related items and there is a limitation of one-thousand dollars ($1,000) per review of each JWA Quarterly Noise Report. ~ DISCUSSION J~J. Van Houten and Associates, Inc., Tustin's noise consultants, prepared a review of the most recent County-prepared John Wayne Airport Noise. Abatement Program quarterly report for the 2nd quarter o$ 1993. A copy of their report is attached. ~or the second quarter of 1993 there has been a decrease in the Community Noise Equivalent Level (CNEL) at monitoring station M7 in Tustin of one-tenth (.1) of a decibel compared with the previous quarter. However, during the second quarter, the number of aircraft operations increased to a total of 16,412 for the quarter from the previous quarter total of 15,560. Based on data for the first and second quarters of 1993, it is estimated that the annual average CNEL at station M7 will be 56.7 dB for 1993. This is four-tenths (.4) of a decibel higher than the average annual CNEL of~ 56.3 dB for 1992. However, this is below the City, County, and State criteria of 65 dB for residential areas. The number of quarterly noise complaints for Tustin/Orange increased for this quarter although the average CNEL remained relatively the same as the first quarter. The increase may be attributable to 'the increase in overall flights in the second quarter compared to the first. However, the classification of aircraft used that would be attributable to the increase in flights was the quietest classification type. city Council Report Airport StatUs Report January 17, 1994 Page 2 The consultant has again analyzed the relationship between changes in CNEL and the number of quieter aircraft put into service at John Wayne Airport. The analysis shows that the percentage of quiet Class E aircraft is increasing slightly f~om 1992 into the first and second quarters of 1993. Class E aircraft are the quietest of the three types of aircraft (Class A, AA and E) unique to John Wayne Airport. However,. the classification only applies to departures and in some cases, aircraft classified as Class E are actually noisier on arrival than some Class A and AA aircraft. Therefore, the percentage of Class E aircraft does not significantly affect noise levels at Tustin's noise monitoring station. As a result, it is difficult to correlate the types of aircraft flown with the measured CNEL. 'CONCLUSION Because the issues discussed above are of considerable importance to the City of Tustin, the Community Development Department wi~ continue to monitor airport issues unless otherwise directed by Council. ~n~ E. Bonner Associate'Planner Community Development Attachments: Report from J.J. Van Houten and Associates Rg :AB: kd\CCREPORT\a i rpst a6. aeb J.J. VAN HOUTEN & ASSOCIATES, Inc. JOHN J. VAN HOUTEN, PE, Principal Consultant DAVID L. WIELAND, Principal Engineer ROBERT WOO, Senior Engineer 1260 EAST KATELLA AVENUE. .~NAHELM. C.M.IFORNIA 92805 |714) 978-7018 {71..~ 635-9520 F.~X {714) 939-0648 December 15, 1993 CITY OF TUSTIN Community Development Department 300 Centennial Way Tustin, CA 92680 Project File 2306-91 Attention: Ms. Rita Westfield Subject: Review of John Wayne Airport Noise Abatement Program Quar:erly Report, 2nd Quarter 1993 Reference: 1. "Data Evaluation and Aircraft Noise Impact Study for the City of Tustin," J. J. Van Houten and AssoCiates, Inc., January. 8, 1990 . "Noise Abatement Program Quarterly Report for the Per/od: Ap?il 1, 1993 through June 30, 1993," John Wayne Airport Dear Ms. Westfield: Als requested, we have reviewed the referenced quarterly report for the noise abatement program at John Wayne Airport. The following provides our findings with regard to airport operations and their impact on the City of Tustin: Referring to Figures 1 and 2, the average annual CNEL at station M7 Mll be 56.7 dB for 1993 based upon data for the 1st and 2nd quarters. This is 0.4 dB higher than the average annual CNEL of 56.3 dB for 1992. (NOTE: The noise contours for John Wayne Airport are based on average annual CNEL values measured at each remote monitoring station.) It should be noted that the average annual CNEL is skewed by the lack of data for the entire month of January. and 35 days throughout the 1st and 2nd quarters, including a continuous 21 day period in April and May. . _. Referring to Figure 2, there does not appear to be any correlation between the average number of noise complaints received from the Tustin/Orange area and the average quarterly aircraft CNEL or the average quarterly number ol jet operations. As indicated in the figure, the number of noise complaints was significantly higher in the second quarter of 1993 than in the first quarter even ge though the average quarterly CNEL remained the same. Referring to both Table 2 and Figure 2, the number of complaints also does not correlate with the percentage of noisier aircraft (Class A and AA) landing at the airport. As indicated in Item 1, above,' the annual average CNEL measured at station M7 will be about 57 dB based on information through the second quarter of 1993. This is slightly less than the 58 dB that was estimated for the station in the referenced aircraft noise impact study for the Phase 2 Access Plan (Reference 1). AIRCRAFT NOISE CONTOURS In 1988, an exterior aircraft noise monitoring effort was conducted throughout the City of Tustin by the John Wayne Airport Noise Abatemem Office and by J. J. Van Houten and Associates, Inc. (Reference 1). Aircraft-generated single event noise exposure levels (SENEL's) were measured at twelve locations in Tustin over a five momh period. As-a result of this effort, noise contours were developed for John Wayne .Airport as they .impact the City of Tustin. Although the shape of the contours does not change (since flight tracks are fixed), the value of the noise contours does change with different levels of operations at the airport and different mixes of aircraft. , Figure 3 provides the approximate location of the John Wayne Airport noise contours for 1990 based on measurements obtained at monitoring station M7 throughout the year. Referring to the figure, the community noise equivalent level (CNEL) ranged from 53 to 5~}-dB in the City of Tustin, with a CNEL of about 55 dB at station M7. · Based on data through the second quarter, the annual average CNEL at station M7 will be 57 dB in 1993. The existing and future Phase 2 contours (based on 1993 data) are ,provided in Figure 4. Referring to the figure, it is estimated that in 1993 the aircraft- generated CNEL will range from 55 to 61 dB. This is well below the City, County, and State criteria of 65 dB for residential areas. USE OF QUIETER AIRCRAFT AT JWA As requested, we have analyzed the correlation between the increasing use of quieter aircraft at JWA and the change in CNEL within the City of Tustim The Federal Aviation Administration (FAA) classifies aircraft into three categories based on noise levels. In order of decreasing noise levels, there axe Stage I, Stage 1I, and Stage m ~r~raft. John Wayne Airport has only permitted Stage m aircraft since the early 1970's. CITY OF TUSTIN 2 Project File 230691 j.j. VAN HOUTEN & ASSOCIATES, Inc. The airport has its own classification scheme for passenger aircraft. In order of decreasing noise level, these are Class A, Class AA, and Class E aircraft. Table 1 provides the estimated number of each class of aircraft that used the airport between the first quarter of 1992 and the second quarter of 1993. Also provided is the measured average quarterly CNEL at monitoring station M7. Table 2 provides the same information, but the values have been normalized to 17,000 aircraft operations (takeoffs and landings) per quarter. In this way, a correlation can be established between the quarterly CNEL mad the mix of aircraft types. Referring to Table 2 and Figure 5, the percentage of quieter Class E aircraft using John Wayne Airport was higher in the 2nd quarter of 1993 than in the 1st quarter (about 26%). This increase in Class E aircraft was offset by decrease in the use of the noisier Class AA aircraft. With this increase in quieter aircraft the weighted average quarterly CNEL decreased slightly. If you have any questions, please contact the undersigned at 714/978-7018. Very truly yours, j. J. VAN HOUTEN & ASSOCIATES, INC. //~ J. Va/ff~Iouten, P.E. ' ' ~//C .oxxsultin~/r~n~neer in Acoustics nnc~pal Consultant CITY OF TUSTIN 3 e~oj~ me 230~9~ J.J. VAN HOUTEN & ASSOCIATES, Inc. 0 z Z 0 Z Z 'T' 0 Z 0 z · 000000 000000 C) C) O C) C) 0 , '~-' '~'1'-- 0 (~1 0 I"-- 0 CO O O~ 0'~ I 0 O0o ..0 0 07 (gP) -I~iNO 8O 60 4O 2O 2O 15 ~ 10 0 100 8O 6O 4O 2O 0 I A__.V_e_?g___e__._Q___U_a_~.e_~.y_.~_r__c_r___a _ft CN EL; 1Qt~2 2Qtr92 3Qtr92 4Qtr92 1Qtr93 2Qtr93 Quarter/Year 1Qtr92 I Total Quarterly Jet Operations, M7 1 2Qtr92 I 3Qtr93 I 4Qtr93 3Qtr92 4Qtr92 1Qtr93 2Qtr93 3Qtr93 4Qtr93 Quarter/Year I Average Quarterly Noise Complaints 1Qff92 2Qtr92 3Qtr92 4Qtr92 1Qtr93 2Qtr93 Quarter/Year 3Qtr93 Figure 2 4Qtr93 M-? ,'5 i ¼ II ,,* . II l! // // // // //. // // Figure 3. Approximate Location of John Wayne Airport Noise Contours, 1990 M-7 6 60 59 58 57 56 55 Figure 4. Approximate Location of John Wayne Airport Noise Contours, 1992 ¸if o I I I spuesnoql SNOLL~:I:JdO l..~V'elO~lV :JO ~381AtflN o