University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 12-2003 Identification of aircrew tasks for using direct voice input (DVI) to reduce pilot workload in the AH-64D Apache Longbow Donald James Hunter Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Recommended Citation Hunter, Donald James, "Identification of aircrew tasks for using direct voice input (DVI) to reduce pilot workload in the AH-64D Apache Longbow. " Master's Thesis, University of Tennessee, 2003. https://trace.tennessee.edu/utk_gradthes/5239 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Donald James Hunter entitled "Identification of aircrew tasks for using direct voice input (DVI) to reduce pilot workload in the AH-64D Apache Longbow." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Aviation Systems. Ralph Kimberlin, Major Professor We have read this thesis and recommend its acceptance: Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a thesis written by Donald JamesHunter entitled "Identification Of Aircrew Tasks For Using Direct Voice Input (DVI) To Reduce Pilot Workload In The AH-64D Apache Longbow." I have examined the finalpaper copy of this thesis for form and content and recommend that it be accepted in partial fulfillmentof the requirements forthe degree of Master of Science, with a major in Aviation Systems. We have read this thesis and recommend its acceptance: @�� Acceptance forthe Council: Vice Provost and D an Graduate Studies IDENTIFICATION OF AIRCREW TASKS FOR USING DIRECT VOICE INPUT (DVI) TO REDUCE PILOT WORKLOAD IN THE AH-64D APACHE LONGBOW A Thesis Presented for the Master of Science Degree The :Universityof Tennessee, Knoxville \ Donald James Hunter December 2003 DEDICATION This thesis is dedicated to all the men and women that support, fly, and maintain the AH-64 Apache. Attack! ii ACKNOWLEDGEMENT I would like to express many thanks to the faculty and staffof the Aviation Systems Department who have made my stay here at the University of Tennessee Space Institute challenging and enjoyable. I am gratefulto my thesis committee, Dr. Ralph Kimberlin, and Dr. Peter Solies, for their wisdom and guidance, and to ProfessorRich Ranaudo for the many air miles and hours spent helping me prepare this thesis. I would also like to acknowledge the technical support of Tim Roderick and Ty Crowder whose years of expertise flying the Apache proved invaluable. Special thanks to Matt Hannen, Crew Systems and Human Factors Engineer forBoeing Co. Mesa, Arizona, for his assistance in directing the focusof this thesis and answering the many questions I posed. Additionally, I would like to thank the wonderful Allison Schmidt for her understanding and support in helping me write this thesis. iii ABSTRACT Advances in helicopter design continue to saturate the pilot's visual channel and produce remarkable increases in cognitive workload forthe pilot. This study investigates the potential implementation of Direct Voice Input (DVI) as an alternativecontrol for interacting with onboard systems of the AH-64D Apache, in an attempt to reduce pilot workload during a "hands on" the controls and "eyes out" condition. The intent is to identify AH-64D cockpit tasks performedthrough Multi Purpose Displays (MPDs) that when converted to DVI will provide the greatest reduction in task execution time and workload. A brief description of applicable AH-64D audio and visual displays are provided. A review of current trends in state-of-the-art voice recognition technology is presented, as well as previous and currentvoice input cockpitidentification studies. To identify tasks in the AH-64D, a methodologywas developed consisting of a detailed analysis of the aircraft's mission and on-board systems. A pilot questionnaire was developed and administered to operational AH-64D pilots to assess their input on DVI implementation. Findings indicate DVI would be most useful fordisplaying selected MPD pages and performing tasks pertainingto the Tactical Situation Display (TSD), weapons, and communications. Six of the candidate DVI tasks were performed in the AH-64D simulator using the manual input method and a simulated voice input method. Two differentpilots made objective and subjective evaluations. Task execution times and workload rating were lower using a simulated means of voice input. Overall, DVI shows limited potential forworkload reduction and warrants further simulator testing beforeproceeding to the flightenvironment. iv TABLE OF CONTENTS CHAPTERI IN"TRODUCTION................................................................................................... 1 Preface.......................................................................................................... ! Statement of the Problem .............................................................................1 A Proposed Solution ....................................................................................3 Thesis Statement ..........................................................................................3 Structural Overview of Thesis .....................................................................4 CHAPTER2 BACKGROUND .....................................................................................................6 Introduction ..................................................................................................6 The Evolution of the AH-64D Attack Helicopter ........................................6 Background Conclusion .............................................................................19 CHAPTER3 SYSTEM DESCRIPTION..................................................................................... 21 AH-64D: General Description ...................................................................21 Data Management System ......................................................................... 22 Warning, Caution and Advisory System ...................................................32 CHAPTER4 LITERATURE REVIEW...................................................................................... 34 Multiple Resource Theory .........................................................................34 Acoustic Theory .........................................................................................36 V Speech Recognition Technology .............................................................. .39 Speech Recognition In The Flight Environment ...................................... .47 Direct Voice Input CockpitResearch ........................................ � ............... 50 Voice Input Task Identification Studies .................................................... 52 CHAPTERS METHODOLOGY ................................................................................................58 Introduction ................................................................................................ 58 Description of the Test Simulator .............................................................. 59 Module One: Mission Analysis .................................................................61 Module Two: Task Identification ..............................................................64 Module Three: Pilot Questionnaire ............................................................ 68 Module Four: Simulator ....................................................................·......... 69 CHAPTER6 FINDINGS AND DISCUSSION ...........................................................................73 Module One Findings: Mission Analysis ..................................................73 Module Two Findings: Task Identification............................................... 75 Module Three Findings: Pilot Questionnaire .............................................75 Module Four Findings: Simulator ..............................................................88 CHAPTER7 CONCLUSION & RECOMMENDATIONS........................................................ 94 Conclusion .................................................................................................94 Recommendations ......................................................................................96 LIST OF REFERENCES ................................................................................................ 98 vi APPENDICES ................................................................................................................104 APPENDIXA: MISSION OUTLINE .................................................................105 APPENDIX B: MODULE TWO DATA .............................................................114 APPENDIX C: PILOT QUESTIONNAIRE .......................................................125 APPENDIX D: BEDFORD SCALE................................................................... 138 APPENDIXE: SLALOM COURSE ...................................................................140