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Validation Protocol for Digital Audio Recorders Used in Aircraft-Noise- Certification Testing” (Validation Protocol)

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U.S. Department of Validation Protocol for Digital Audio Transportation Recorders Used in Aircraft-Noise- Federal Aviation Administration Certification Testing FAA-AEE-2010-05 DOT-VNTSC-FAA-11-02 Final Report NTIS No. PB2011-102068 November 2010 Prepared for: Prepared by: U.S. Department of Transportation U.S. Department of Transportation Federal Aviation Administration Research and Innovative Technology Administration Office of Environment and Energy John A. Volpe National Transportation Systems Center Washington, D.C. 20590 Environmental Measurement and Modeling Division, Acoustics Facility Cambridge, MA 02142 Notice This document is disseminated under the sponsorship of the Department of Transportation in the interest of in- formation exchange. The United States Government assumes no liability for its contents or use thereof. Notice The United States Government does not endorse prod- ucts or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered es- sential to the objective of this report. ii Form Approved REPORT DOCUMENTATION PAGE OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, in- cluding the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this bur- den, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Re- duction Project (0704-0188), Washington, DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES November 2010 COVERED Final Report 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Validation Protocol for Digital Audio Recorders Used in Aircraft-Noise-Certification Testing FA4TC3 – JS889 6. AUTHOR(S) Samiljan, Robert, Fleming, Gregg, Read, David, Roof, Christopher 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION U.S. Department of Transportation REPORT NUMBER Research and Innovative Technology Administration John A. Volpe National Transportation Systems Center DOT-VNTSC-FAA-11-02 Environmental Measurement and Modeling Division, RVT-41 Cambridge, MA 02142-1093 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10.SPONSORING/MONITORING AGENCY REPORT NUMBER U.S. Department of Transportation Federal Aviation Administration Office of Environment and Energy, AEE-100 FAA-AEE-2010-05 Washington, DC 20591 11. SUPPLEMENTARY NOTES Support provided by Raquel Girvin, Mehmet Marsan, and Joe DiPardo of FAA AEE-100, Of- fice of Environment and Energy, Noise Division. 12a. DISTRIBUTION/AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE 13. ABSTRACT (Maximum 200 words) The U.S. Department of Transportation, Research and Innovative Technology Administra- tion, John A. Volpe National Transportation Systems Center, Environmental Measurement and Modeling Division (Volpe), is supporting the aircraft noise certification initia- tives of the Federal Aviation Administration (FAA), Office of Environment and Energy (AEE) by preparing the “Validation Protocol for Digital Audio Recorders Used in Air- craft-Noise-Certification Testing” (Validation Protocol). As analog and digital tape- based recording devices are becoming obsolete, this Validation Protocol has been devel- oped for applicants requesting permission from FAA/AEE to conduct aircraft noise certi- fication testing using non-tape-based recorders. Because of the significant differences between non-tape-based recording devices and all preceding technologies, this Protocol establishes a set of procedures for testing and evaluating the performance of non-tape- based digital audio recorders proposed for aircraft noise certification use. If using any of the digital audio recording devices covered by the scope of this document, it is recommended that an applicant perform tests to evaluate the characteristics of the re- cording device in accordance with the guidance in the Validation Protocol to demonstrate compliance with part 36 Title 14 of the Code of Federal Regulations (Part 36) and Inter- national Civil Aviation Organization Annex 16 Volume I (ICAO Annex 16). 14. SUBJECT TERMS 15. NUMBER OF PAGES Aircraft noise, noise certification, instrumentation, noise measure- 33 ments, noise 16. PRICE CODE 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICA- 20. LIMITATION OF AB- OF REPORT OF THIS PAGE TION STRACT OF ABSTRACT Unclassified Unclassified Unclassified NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89) Prescribed by ANSI Std. 239-18 298-102 iii METRIC/ENGLISH CONVERSION FACTORS ENGLISH TO METRIC METRIC TO ENGLISH LENGTH (APPROXIMATE) LENGTH (APPROXIMATE) 1 inch (in) = 2.5 centimeters (cm) 1 millimeter (mm) = 0.04 inch (in) 1 foot (ft) = 30 centimeters (cm) 1 centimeter (cm) = 0.4 inch (in) 1 yard (yd) = 0.9 meter (m) 1 meter (m) = 3.3 feet (ft) 1 mile (mi) = 1.6 kilometers (km) 1 meter (m) = 1.1 yards (yd) 1 kilometer (km) = 0.6 mile (mi) AREA (APPROXIMATE) AREA (APPROXIMATE) 1 square inch (sq in, in2) = 6.5 square centimeters (cm2) 1 square centimeter (cm2) = 0.16 square inch (sq in, in2) 1 square foot (sq ft, ft2) = 0.09 square meter (m2) 1 square meter (m2) = 1.2 square yards (sq yd, yd2) 1 square yard (sq yd, yd2) = 0.8 square meter (m2) 1 square kilometer (km2) = 0.4 square mile (sq mi, mi2) 1 square mile (sq mi, mi2) = 2.6 square kilometers (km2) 10,000 square meters (m2) = 1 hectare (ha) = 2.5 acres 1 acre = 0.4 hectare (he) = 4,000 square meters (m2) MASS – WEIGHT (APPROXIMATE) MASS – WEIGHT (APPROXIMATE) 1 ounce (oz) = 28 grams (gm) 1 gram (gm) = 0.036 ounce (oz) 1 pound (lb) = 0.45 kilogram (kg) 1 kilogram (kg) = 2.2 pounds (lb) 1 short ton = 2,000 pounds = 0.9 tonne (t) 1 tonne (t) = 1,000 kilograms (kg) (lb) = 1.1 short tons VOLUME (APPROXIMATE) VOLUME (APPROXIMATE) 1 teaspoon (tsp) = 5 milliliters (ml) 1 milliliter (ml) = 0.03 fluid ounce (fl oz) 1 tablespoon (tbsp) = 15 milliliters (ml) 1 liter (l) = 2.1 pints (pt) 1 fluid ounce (fl oz) = 30 milliliters (ml) 1 liter (l) = 1.06 quarts (qt) 1 cup © = 0.24 liter (l) 1 liter (l) = 0.26 gallon (gal) 1 pint (pt) = 0.47 liter (l) 1 quart (qt) = 0.96 liter (l) 1 gallon (gal) = 3.8 liters (l) 1 cubic foot (cu ft, ft3) = 0.03 cubic meter (m3) 1 cubic meter (m3) = 36 cubic feet (cu ft, ft3) 1 cubic yard (cu yd, yd3) = 0.76 cubic meter (m3) 1 cubic meter (m3) = 1.3 cubic yards (cu yd, yd3) TEMPERATURE (EXACT) TEMPERATURE (EXACT) [(x-32)(5/9)] F = y C [(9/5) y + 32] C = x F QUICK INCH - CENTIMETER LENGTH CONVERSION 0 1 2 3 4 5 Inches Centimeters 0 1 2 3 4 5 6 987 1110 1312 QUICK FAHRENHEIT - CELSIUS TEMPERATURE CONVERSION °F -40° -22° -4° 14° 32° 50° 68° 86° 104° 122° 140° 158° 176° 194° 212° °C -40°-30° -20° -10° 0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100° For more exact and or other conversion factors, see NTIS Miscellaneous Publication 286, Units of Weights and Measures. iv Acknowledgements The authors would like to thank Mr. Alan Marsh for sharing his extensive knowledge and experience in review of this document. His insight and attention to detail have proved in- valuable. v This page intentionally left blank. vi CONTENTS 1.0 INTRODUCTION ............................................................................................... 1 2.0 OBJECTIVES ..................................................................................................... 2 3.0 SCOPE ................................................................................................................ 2 4.0 APPLICABLE STANDARDS .............................................................................. 2 5.0 TERMS AND DEFINITIONS .............................................................................. 3 6.0 ENVIRONMENTAL CONDITIONS FOR VALIDATION TESTS ....................... 6 7.0 TEST INSTRUMENTS ........................................................................................ 7 8.0 DEVICE UNDER TEST (DUT) ........................................................................... 8 9.0 VALIDATION TESTS ........................................................................................ 9 10.0 FEATURES AND PRACTICAL CONSIDERATIONS ....................................... 29 11.0 CHECKLIST FOR A TEST REPORT ................................................................ 31 12.0 SUBMITTAL OF TEST REPORT ..................................................................... 32 13.0 BIBLIOGRAPHY .............................................................................................. 33 TABLES Table 1. Example data and recommended format for presentation of results from level linearity tests .................................................................................................................. 13 Table 2. Example data and recommended format for presentation of results from level- range control testing ....................................................................................................... 20 Table 3. Example data and recommended format for presentation of results from an anti- alias filter test ................................................................................................................ 23 Table 4. Example data and recommended format for presentation of results from a test of inter-channel crosstalk
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