Transcription of Environmental Technical Manual
1 SGAR 1 (CAEP9 Steering Group 3 approved revision) Based on Doc 9501, Volume I, First Edition International Civil Aviation Organization Committee on Aviation Environmental Protection Environmental Technical Manual _____ Volume I Procedures for the Noise Certification of Aircraft (ii) Environmental Technical Manual (SGAR 1) (iii) FOREWORD This revision of Doc. 9501, Volume I, First Edition, includes material which has been approved by the ICAO Committee on Aviation Environmental Protection (CAEP) Steering Group during their third meeting of the CAEP/9 cycle in July 2012.
2 This revision is intended to make the most recent information available to certificating authorities, noise certification applicants and other interested parties in a timely manner, aiming at achieving the highest degree of harmonisation possible. The Technical procedures and equivalent procedures described in this Steering Group approved revision of the ETM are consistent with currently accepted techniques and modern instrumentation. In this respect this Steering Group approved revision of the ETM is compatible with Amendment 10 of Annex 16, Volume I and the changes endorsed by the CAEP Steering Group for Amendment 11 of Annex 16, Volume I.
3 This revision and subsequent revisions that may be approved by the CAEP Steering Group will be posted on the ICAO website ( ) under publications until the latest approved revision is submitted to CAEP for formal endorsement and subsequent publication by ICAO. _____ (iv) Environmental Technical Manual (SGAR 1) (iv) (v) TABLE OF CONTENTS Page FOREWORD .. iii TABLE OF CONTENTS .. v ACRONYMS AND ABBREVIATIONS .. xvii Chapter 1 INTRODUCTION .. 1-1 PURPOSE .. 1-1 DOCUMENT STRUCTURE .. 1-1 EXPLANATORY INFORMATION .. 1-1 EQUIVALENT PROCEDURES.
4 1-2 Technical PROCEDURES .. 1-2 CONVERSION OF UNITS .. 1-2 REFERENCES .. 1-2 Chapter 2 GENERAL GUIDELINES .. 2-1 APPLICABILITY OF CURRENT AND PREVIOUS AMENDMENTS TO ANNEX 16, VOLUME I .. 2-1 CHANGES TO AIRCRAFT TYPE DESIGNS INVOLVING DERIVED VERSIONS .. 2-2 CHANGES TO AIRCRAFT TYPE DESIGNS INVOLVING NO-ACOUSTICAL CHANGES .. 2-2 Modifications to helicopters for which changes in noise level(s) need not be determined .. 2-5 RECERTIFICATION .. 2-5 NOISE COMPLIANCE DEMONSTRATION PLANS .. 2-5 NOISE CERTIFICATION REPORTS .. 2-6 Chapter 3 Technical PROCEDURES APPLICABLE FOR NOISE CERTIFICATION OF ALL AIRCRAFT TYPES 3-1 NOISE MEASUREMENT PROCEDURES.
5 3-1 Test site selection .. 3-1 Terrain .. 3-1 Grass .. 3-1 Snow .. 3-1 Ploughed fields .. 3-1 Obstructions .. 3-2 Anomalous meteorological conditions .. 3-2 Precautions regarding effects of 3-2 General precautions .. 3-2 Effects of moisture on microphones .. 3-2 Microphone internal heaters .. 3-3 Calibration of acoustical measurement system .. 3-3 General calibration process .. 3-3 Frequency-dependent system response corrections .. 3-3 Single-frequency level calibrations .. 3-4 Field sound pressure level calibration considerations.
6 3-5 Application of calibration corrections .. 3-6 (vi) Environmental Technical Manual (Steering Group approved revision) Calibration traceability .. 3-6 Windscreen insertion loss .. 3-6 Wind speed limitations .. 3-6 Measurement of Atmospheric conditions .. 3-7 Meteorological measurement systems .. 3-7 Aircraft position measurement .. 3-7 Measurement system specifications .. 3-7 Validation of measurement system configuration .. 3-7 Changes in measurement system configuration .. 3-7 Noise compliance demonstration plan .. 3-8 FLIGHT PATH MEASUREMENT.
7 3-8 Radar or microwave tracking system .. 3-8 Aircraft equipment .. 3-9 Ground equipment .. 3-9 Kine-theodolite system .. 3-9 Radar/theodolite triangulation .. 3-10 Photographic scaling .. 3-10 DGPS-based time-space-position information tracking systems .. 3-11 General .. 3-11 System design issues .. 3-12 Coordinate frames and waypoint navigation .. 3-12 Test site 3-13 Receiver output data .. 3-14 Data stored during aircraft noise testing when a real-time data link is used .. 3-14 Data stored during aircraft noise testing when a real-time data link is not used.
8 3-14 Real-time DGPS messages .. 3-15 Messages for multi-path testing .. 3-15 System accuracy and sources of DGPS error .. 3-15 Multi-path errors .. 3-16 Characteristics .. 3-16 Code-based system ground station .. 3-16 Carrier-based system ground station .. 3-17 Aircraft installation .. 3-18 Other sources of DGPS error .. 3-18 Correction latency .. 3-18 Tropospheric delay .. 3-18 Mismatched GPS receivers .. 3-19 Mismatched satellite ephemeris/clock data .. 3-19 (vii) System approval recommendations .. 3-19 Design issues .. 3-20 Data storage (logging) during noise testing.
9 3-20 For a system with real-time data link .. 3-20 For a system not using real-time data link .. 3-21 Documentation .. 3-21 Accuracy verification test .. 3-21 Software verification .. 3-21 Ground-station multi-path mitigation and 3-22 All systems .. 3-22 Code-based systems .. 3-22 Airport survey .. 3-22 ON-BOARD FLIGHT DATA ACQUISITION .. 3-22 General .. 3-22 Magnetic tape recording .. 3-23 Automatic still photographic recording .. 3-23 Cine recording .. 3-23 Video recording .. 3-23 TIME SYNCHRONIZATION OF MEASURED DATA.
10 3-24 General .. 3-24 TSPI equipment and software approval .. 3-24 Continuous time-code recording .. 3-24 Recording of single time marker .. 3-25 Measurement of the interval between recorder start and overhead .. 3-25 Setting of internal time-stamp clock .. 3-25 Additional time-synchronization 3-25 CALCULATION OF CONFIDENCE INTERVALS .. 3-26 3-26 Confidence interval for the mean of flight test data .. 3-26 Confidence interval for the sample estimate of the mean of clustered measurements .. 3-26 Confidence interval for mean line obtained by regression.
