TRUE PHOENIX: STATIC SOURCE POSITION ERROR CORRECTIONS FOR THE PITOT-STATIC SYSTEMS ON AN F-16 FALCON by JASON THOMAS DIGIACOMO, B.S., M.B.A. A THESIS IN SOFTWARE ENGINEERING Submitted to the Graduate Faculty of Texas Tech University in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE IN SOFTWARE ENGINEERING Approved Hector J. Hernandez Chairperson of the Committee Susan A. Mengel Accepted John Borrelli Dean of the Graduate School December, 2005 ACKNOWLEDGEMENTS I would like to thank my advisor, Dr. Susan Mengel, for supporting me through this project and guiding me as I traveled around the world in support of Operation Enduring Freedom and through my change of station to Edwards AFB, CA. I would also like to thank the U.S. Air Force in providing me the opportunity to attend Test Pilot School. The U.S. Air Force Test Pilot School is a highly competitive and respective program that allowed me to combine my two passions, aviation and engineering, into a single focus and execute amazing programs such as this one. I also owed special acknowledgement to Lt Col Michael Taschner for his pursuit of the perfect three-leaf cloverleaf and his mathematical genius in improving our brute force spreadsheet into an elegant and efficient data reduction tool. His efforts provided me with an independent verification and validation of the cloverleaf data reduction tools. Finally, I would like to express my gratitude to my parents and wife for supporting me in the pursuit of my dreams and always keeping me firmly planted on earth until they knew I was ready for the stars. ii TABLE OF CONTENTS ACKNOWLEDGEMENTS................................................................................................ ii TABLE OF CONTENTS................................................................................................... iii ABSTRACT.........................................................................................................................v LIST OF TABLES............................................................................................................ vii LIST OF FIGURES AND ILLUSTRATIONS................................................................ viii LIST OF ABBREVIATIONS............................................................................................ xi CHAPTER 1. INTRODUCTION ..........................................................................................................1 1.1 MOTIVATION OF THESIS .......................................................................................2 1.2 PROGRAM CHRONOLOGY.....................................................................................3 1.3 TEST ITEM DESCRIPTION ......................................................................................4 1.4 GOAL OF THESIS......................................................................................................7 1.5 THESIS ORGANIZATION.........................................................................................8 2. LITERATURE REVIEW ...............................................................................................9 2.1 TOWER FLY-BY FLIGHT TEST TECHNIQUE ......................................................9 2.2 CROSS-PACE FLIGHT TEST TECHNIQUE..........................................................13 2.3 ANGLE OF ATTACK FLIGHT TEST TECHNIQUE.............................................16 2.4 CLOVERLEAF FLIGHT TEST TECHNIQUE........................................................18 2.5 LEVEL ACCELERATION / DECELERATION FLIGHT TEST TECHNIQUE....21 2.6 SUMMARY...............................................................................................................23 3. RESEARCH METHODOLOGY..................................................................................24 iii 4. RESEARCH RESULTS ...............................................................................................28 4.1 POSITION ERROR CORRECTIONS ......................................................................29 4.2 TOTAL AIR TEMPERATURE PROBE RECOVERY FACTOR ...........................38 4.3 CLOVERLEAF FLIGHT TEST TECHNIQUE ANALYSIS ...................................40 5. CONCLUSIONS AND FUTURE WORK ...................................................................44 5.1 CONCLUSIONS........................................................................................................44 5.2 RECOMMENDATIONS FOR FUTURE WORK ....................................................46 BIBLIOGRAPHY..............................................................................................................48 APPENDICES A: GRAPHICAL ILLUSTRATIONS..............................................................................49 B: LESSONS LEARNED..............................................................................................114 C: INSTRUMENTATION LIST ...................................................................................118 D: END-TO-END GROUND TEST RESULTS ...........................................................120 E: RAW DATA..............................................................................................................122 F: DATA ANALYSIS PLAN........................................................................................131 iv ABSTRACT This report presents the objectives, procedures, and results of the TRUE PHOENIX test project. TRUE PHOENIX calibrated a “Coral Phoenix” F-16B, S/N 92-0457, to serve as a high-speed pacer aircraft for the calibration of other aircraft air data systems and to replace an older F-16B (S/N 80-0633). Ground testing of the Pitot-static system was conducted from19 February to 5 April 2004, and flight testing was conducted from 7 April to 30 April 2004 with a total of eight successful missions. The pacer instrumentation on F-16B S/N 92-0457 utilized the production F-16B noseboom-mounted air data probes to collect data for both total and static pressure systems. A total air temperature probe was mounted on the underside of the left forebody strake and provided the pacer air data computer with an air temperature measurement. The pacer instrumentation did not affect the performance or flying qualities of the aircraft. The overall test objective was to determine the air data system position error corrections of F-16B S/N 92-0457. This objective was met with marginal results; however, some of the sub-objectives were successfully met. The position error corrections were determined using the tower fly-by and F-15B pace flight test techniques. Independent validation of these position error corrections were attempted using the level acceleration/deceleration and cloverleaf flight test techniques. In addition, a limited investigation into angle of attack effects was accomplished using the constant airspeed turn flight test technique. v Overall, while position error corrections were determined for calibrating F-16B S/N 92-0457, the reliability of the position error corrections at some altitudes were questionable and considered MARGINAL for calibrating F-16B S/N 92-0457 as a high- speed pacer aircraft. Through tower fly-by data analysis, the ground-level position error correction curves were accurately determined. The curves determined by the pace mission had some inaccuracies, particularly at 10,000 feet and 20,000 feet pressure altitude. The data from the level acceleration/deceleration and cloverleaf flight test techniques were not reliable enough to alter these pace curves. It was also determined that the aircraft Pitot-static system was sensitive to small changes in angle of attack. Overall, the difference in results from the various flight test techniques requires further investigation to explain the data scatter. The total air temperature probe testing resulted in a recovery factor of 0.98, slightly below that expected from a flight test probe, and should be investigated for defects. The Pitot-static pacer calibration system software installed in this aircraft was a stable system, satisfactory for use in calibrating future aircraft air data systems. vi LIST OF TABLES 1. Test Mission Chronology................................................................................................3 2. Total Air Temperature Probe Calibration Summary ....................................................39 3. Cloverleaf Wind Analysis.............................................................................................41 4. Cloverleaf Inter-leg Wind Analysis.............................................................................42 5. End-to-End Ground Test Results................................................................................121 6. Tower Fly-by Aircraft Raw Data................................................................................123 7. Fly-By Tower Raw Data (7 April 2004).....................................................................125 8. Fly-By Tower Raw Data (12 April 2004)...................................................................126 9. Fly-By Tower Raw Data (13 April 2004)...................................................................127 10. Fly-By Tower Raw Data (30 April 2004).................................................................128 11. Pace Raw Data ..........................................................................................................129 vii LIST OF FIGURES AND ILLUSTRATIONS 1. F-16B Production ADS with Pacer Connections............................................................6 2. Cloverleaf (Overhead