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Home My WebLink About12 AIRPORT STATUS RPT 06-20-94DATE: JUNE 20, 1994 NO. 12 6-20-94 TO: FROM: SUBJECT: WILLIAM A. HUSTON, CITY MANAGER COMMUNITY DEVELOPMENT DEPARTMENT AIRPORT STATUS 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 3rd quarter of 1993. A copy of their analysis is attached. For the third quarter of 1993 there has been an increase in the Community Noise Equivalent Level (CNEL) at monitoring station M7 in Tustin of three-tenths (.3) of a decibel compared with the previous quarter. Additionally, during the third quarter, the number of aircraft operations continued to increase to a total of 16,704 for the quarter from the previous quarter total of 16,412. Based on data for the first, second and third quarters of 1993, it is estimated that the annual average CNEL at station M7 will be 56.8 dB for 1993. This is five-tenths (.5) 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 continued increase in overall flights in the second and third quarters compared to the first. Additionally, the classification of aircraft primarily used that would be Ciny Council Report Airport Status Report June 20, 1994 Page 2 atnributable to the increase in flights was the noisiest of the three classification types (Class A). ' The consultant has again analyzed the relationship between changes in CNEL and the number of quieter aircraft put into servi-= at John Wayne Airport. The analysis shows that the percentage of quiet Class E aircraft decreased by about 23% this quarter from the second quarter 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, iherefore, the percentage of. Class E aircraft does not significann!y affect noise levels at Tustin's noise monitoring station. As a result, it is difficult to correlate the types of aircraft flowr, with the measured CNEL. CONCLUSION Because the issues discussed above are of considerable importance to the City of Tustin, the Community Development Deparnment will continue to monitor airport issues unless otherwise directed by Council. k~e~ E. Bonnet~ Associate Planner k~t~ Wesq/'fieid ~ Assistant Director of Community Developmen5 RW: At~: kd\CCREPOR T \a i rpstaT, aeb Attachments: Report from J.J. Van Houten and Associates J.J. VAN HOUTEN & ASSOCIATES, Inc. JOHNJ. VAN HOUTEN, PE Principal Consultant DAVID L. WIELAND, Prix~pal Consultant 1260 EAST KATELL-~ AVENUE, .-~NAHEIM, CALIFORNIA 92805 [714} 978-7018 {714} 635-9520 FAX {714)939-0648 May 19, 1994 Project File 2306-91 CITY OF TUSTEN Community Development Department .. -_-, ..... 300 Centennial Way Tustin, CA 92680 Attention: Ms. Rita Westfield Subject: Review of John Wayne Airport Noise Abatement Program Quarterly Report, 3rd 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 e "Noise Abatement Program Quarterly Report for the Period: July 1, 1993 through September 30, 1993," John Wayne Airport Dear Ms. Westfield: As 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: lo Referring to Figures 1 and 2, the average annual CNEL at station M7 will-be 56.8 dB for 1993 based upon data for the 1st through 3rd quarters. This is 0.5 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 a lack of data for the entire month of January, 12 additional days throughout the 1st quarter, 45 days throughout the 2nd quarter (including a continuous 21 day period in April and May), and 11 days throughout the 3rd qu~-ter. e 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 of jet operations. As indicated in the figure, the number of noise complaints was higher . in the third quarter of 1993 than in the first and second quarters even 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. Between the first and second quarters of 1993, the number of complaints increased significantly though the percentage of noisier aircraft remained the same. However, between the second and third quarters the number of complaints increased slightly, pdrhaps as a result of an increased percentage of Class A operations. 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 Abatement Office and by J. J. Van Houten and Associates, Inc. (Reference 1). Aircraft-generated single event noise exposure levels (SEN'EL's) were measured at twelve locations in Tustin over a five month period. As a result of this effort, noise contours were developed for John Wayne Airport as they impact the City of Tustim 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 59 dB in the City of Tustin, with a CNEL of about. 55 dB at station M7. Based on data through the third 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 Tustin. The Federal Aviation CITY OF TUSTIN 2 Project File 2306-91 J.J. VAN HOUTEN & ASSOCIATES, Inc. Administration (FAA) . classifies aircraft into three categories based on noise levels. In order of decreasing noise levels, there are Stage I, Stage II, and Stage III aircraft. John Wayne Airport has only permitted Stage III aircraft since the early 1970's. 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 esot!m~a~ted n.u.mber of each class of aircraft that used the airport between the first quarter ot lug'z ano the third 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 thi.q way, a correlation can be established between the quarterly CNEL and the mix of aircraft types. Referring to Table 2 and Figure 5, the percentage of quieter Class E aircraft using John Wayne Airport was lower in the 3rd quarter of 1993 than in the 2nd quarter (about 23%). This decrease in Class E aircraft was offset by an increase in the use of the noisier Class A aircraft. With this decrease in quieter aircraft the weighted average quarterly CNEL increased slightly. If you have any questions, please contact the undersigned at 714/978-7018. Very truly yours, J. J. VAN HOUTEN & ASSOCIATES, INC. C~l~ng EnHgte;rn' ffa'~coustics ~//221\reports\230049\~93 . crrY OF TUSTIN Project File 2306-91 j.j. VAN HOUTEN & ASSOCIATES, Inc. l-- n~ 0 Z Z Z Z Z IJJ 0 Z ~ i,.: d ,--: d d ~' 0000000 OC:)O C) C)(:~lC) ~o o O--oo ~c~~c~-C (e~)) '~NO 8O j- LU 60 Z 0 ~ 40 ~ 20 [Average Quarterly Aircraft CNEL, M7 ~ 20 1Qtr92 2Qtr92 3Qtr92 4Qtr92 1Qtr93 2Qtr93 3Qtr93 4Qtr93 Quarter/Year [Total Quarterly Jet Opemlions, M7 [ 100 1Qtr92 2Qtr92 3Qtr92 4Qtr92 1Qtr93 · 2Qtr93 Quarter/Year [Average Quarterly Noise Complaints 3Qtr93 4Qtr93 E 80 0 '~ 60 z I,,.,, e 40 0 e 20 o 1Qtr92 2Qtr92 3Qtr92 4Qtr92 1Qtr93 2Qtr93 3Qtr93 4Qtr93 Quarter/Year Figure 2. Figure 3. Approximate Location of John Wayne Airport Noise Contours, I990 M-7 i · · / . II l! // // // // 6 ?~- 56 55 Figure 4. Approximate Location of John Wayne Airport Noise Contours, 1992 I I I o ~ o ~ 0~1 ~-. ~_ o spuesnoql SNOI.I.V~3dO J._-I'V'dO~l¥ :10