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Adventures in Low Disk Loading VTOL Design NASA/TP—2018–219981 Adventures in Low Disk Loading VTOL Design Mike Scully Ames Research Center Moffett Field, California Click here: Press F1 key (Windows) or Help key (Mac) for help September 2018 This page is required and contains approved text that cannot be changed. NASA STI Program ... in Profile Since its founding, NASA has been dedicated • CONFERENCE PUBLICATION. to the advancement of aeronautics and space Collected papers from scientific and science. The NASA scientific and technical technical conferences, symposia, seminars, information (STI) program plays a key part in or other meetings sponsored or co- helping NASA maintain this important role. sponsored by NASA. The NASA STI program operates under the • SPECIAL PUBLICATION. Scientific, auspices of the Agency Chief Information technical, or historical information from Officer. It collects, organizes, provides for NASA programs, projects, and missions, archiving, and disseminates NASA’s STI. The often concerned with subjects having NASA STI program provides access to the NTRS substantial public interest. Registered and its public interface, the NASA Technical Reports Server, thus providing one of • TECHNICAL TRANSLATION. the largest collections of aeronautical and space English-language translations of foreign science STI in the world. Results are published in scientific and technical material pertinent to both non-NASA channels and by NASA in the NASA’s mission. NASA STI Report Series, which includes the following report types: Specialized services also include organizing and publishing research results, distributing • TECHNICAL PUBLICATION. Reports of specialized research announcements and feeds, completed research or a major significant providing information desk and personal search phase of research that present the results of support, and enabling data exchange services. NASA Programs and include extensive data or theoretical analysis. Includes compilations For more information about the NASA STI of significant scientific and technical data program, see the following: and information deemed to be of continuing reference value. NASA counterpart of peer- • Access the NASA STI program home page reviewed formal professional papers but has at http://www.sti.nasa.gov less stringent limitations on manuscript length and extent of graphic presentations. • E-mail your question to [email protected] • TECHNICAL MEMORANDUM. • Phone the NASA STI Information Desk at Scientific and technical findings that are 757-864-9658 preliminary or of specialized interest, e.g., quick release reports, working • Write to: papers, and bibliographies that contain NASA STI Information Desk minimal annotation. Does not contain Mail Stop 148 extensive analysis. NASA Langley Research Center Hampton, VA 23681-2199 • CONTRACTOR REPORT. Scientific and technical findings by NASA-sponsored contractors and grantees. NASA/TP—2018–219981 Adventures in Low Disk Loading VTOL Design Mike Scully Ames Research Center Moffett Field, California National Aeronautics and Space Administration Ames Research Center Moffett Field, CA 94035-1000 September 2018 Available from: NASA STI Support Services National Technical Information Service Mail Stop 148 5301 Shawnee Road NASA Langley Research Center Alexandria, VA 22312 Hampton, VA 23681-2199 [email protected] 757-864-9658 703-605-6000 This report is also available in electronic form at http://ntrs.nasa.gov Table of Contents Introduction ......................................................................................................................................1 Getting Started .................................................................................................................................1 On to MIT ........................................................................................................................................4 Finding My Place .............................................................................................................................7 Joining the Army Labs (AMRDL) ...................................................................................................8 HELCOM—My First Joint Service Preliminary Design Study ......................................................9 Advanced Attack Helicopter (AAH) Source Selection .................................................................10 AAH SSEB Performance Factor ....................................................................................................11 AAH SSEB Flight Test and Wind Tunnel Test Data ....................................................................13 AAH SSEB Rotor Performance .....................................................................................................15 AAH SSEB Comprehensive Analysis (C81) .................................................................................17 AAH SSEB Technical Reviews and Issues ...................................................................................18 AAH SSEB Wrap-up and Aftermath .............................................................................................20 Preliminary Design Team Consolidation and Design Tool Development .....................................21 Advanced Scout Helicopter (ASH)—My First Concept Formulation ...........................................24 Team Building and Tool Building .................................................................................................28 Vertical Takeoff and Landing (VTOL) Aircraft ............................................................................30 Joint Services Advanced Vertical Lift Aircraft (JVX) ..................................................................31 JVX Joint Technology Assessment (JTA) .....................................................................................32 JVX Joint Service Missions ...........................................................................................................33 JVX JTA Technical Foundations ...................................................................................................34 JVX JTA Weight and Cost Impact of Technology and Special Requirements .............................34 JVX JTA Turboshaft Engine Technology .....................................................................................35 JVX JTA Rotor Aeromechanics Technology ................................................................................36 JVX JTA Airframe Aerodynamics Technology ............................................................................38 JVX JTA Rotorcraft and V/STOL Design Codes ..........................................................................39 JVX JTA Layout Design ................................................................................................................39 JVX JTA Point Designs .................................................................................................................46 JVX JTA Commonality Designs ...................................................................................................49 JVX System Specification Design .................................................................................................50 JVX Program Briefings..................................................................................................................52 iii Table of Contents (cont.) JVX Request for Proposal (RFP) Task Force ................................................................................53 JVX Acquisition Strategy and Competition ..................................................................................54 JVX Program Funding and Executive Service ..............................................................................54 JVX Source Selection and Development Risk ...............................................................................55 Observations ..................................................................................................................................56 Friends, Colleagues, and Mentors ..................................................................................................57 References ......................................................................................................................................58 Index ..............................................................................................................................................64 iv Adventures in Low Disc Loading VTOL Design Dr. Mike Scully, Emeritus Engineer Ames Research Center Introduction This memoir covers the first 8 years of my 37-year career in vertical takeoff and landing (VTOL) aircraft design. It starts with family and how I came to be an engineer with a passion for aviation and a desire to make a difference. At the Massachusetts Institute of Technology (MIT) I acquired a solid understanding of basic physics, learned the basics of the various engineering disciplines, and gained design experience. After over a decade on the East Coast, I was homesick for Northern California. I decided to take a chance on working for the government instead of industry in order to return home. I was hired by Dr. Richard M. Carlson in March 1975 and joined a wonderful Army/NASA technical environment. The Interservice Helicopter Commonality Study (HELCOM) was an important introduction to Joint Service aircraft design. The Advanced Attack Helicopter (AAH) Source Selection Evaluation Board (SSEB) was an opportunity to learn acquisition system fundamentals and to lead
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