Joint Strike Fighter JSF and the JSF Logo

‘Joint Strike Fighter’, JSF, and the JSF Logo are Trademarks of the United States Government Joint Strike Fighter – Prognostics and Health Management (PHM) Michael Gandy and Kevin Line Lockheed Martin Aeronautics . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Public Released Under: AER 200307014 Lockheed Martin Aeronautics Company

What is JSF? Sortie Generation Rate Availability Mission Reliability Single Engine Safety Mission Reliability Reduced Support Equipment Supply Chain Management Training Costs Manpower Logistic Footprint Maintenance Data-link Condition Based Maintenance. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 2

JSF PHM Introduction • Legacy Air Vehicle Shortfalls – High rates (Approx. 30%) of “Could Not Duplicate”, “Bench Check Serviceable”, and “Re-Test OK”. – High Rates of False Alarms and Intermittents – Excessive MTTR (Mean Time To Repair), Spares, Diagnostic Man-Hours, Test Equipment – Excessive Scheduled Maintenance – Poor Mission Reliability – No Timely Warning of Impending Failures HIGH “LIFE CYCLE COST” FOR THE CUSTOMER!. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 3

JSF PHM Introduction • PHM Solution: • Apply Emerging Software and Sensor Technologies – Information Fusion – Model Based Reasoning – Tailored Algorithms – Feature Extraction – High Level Corroboration, Correlation, and Management • Put Fleet Wide Autonomic-Logistics “In The Loop” • Provide a Dedicated Maintenance Reasoner to Automate Fault Detection, Isolation, and Prognostics. REDUCED “LIFE CYCLE COST” FOR THE CUSTOMER!. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 4

PHM Architecture and Enabling Technologies Air Vehicle On-Board Health Assessment ICAWS Manager PHM Area Managers Propulsion Vehicle Systems Health Management, Reporting & Recording Flight Critical NVM Crash Recorder Autonomic Logistics & Off-Board PHM Results In: Displays & Controls PVI Provides: • AV-Level Info Management • Intelligent FI • Prognostics/Trends • Auto. Logistics Enabling/Interface Mission Critical PHM Data PMD AMD/PMD . In-Flight & Maintenance Data Link AVPHM FCS/Utility Subsystems Hosted in ICP ALIS Structures Maintenance Interface Functions Methods Used: Mission Systems MS Subsystems Hosted in ICP • Decision Support • Troubleshooting and Repair • Condition-Based Maintenance • Efficient Logistics • Sensor Fusion • Model-Based Reasoning • Tailored Algorithms • Systems Specific Logic / Rules • Feature Extraction PHM / Service Info MAINTAINER VEHICLE INTERFACE PMA IETMs Consumables On-Board Diagnostics. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. • Automated Pilot / Maint. Debrief • Off-Board Prognostics • Intelligent Help Environment • Store / Distribute PHM Information Database Lockheed Martin Aeronautics Company

PHM Basic Functional Data Flow Current/Predicted MS Status/Assessment PHM Data (Analyzed/Param) Consumables Config Info A/C Parameters SW Errors Current/Predicted Subsystem Status/Assessment PHM Data (Analyzed/Param) Consumables Config Info A/C Parameters SW Errors FDI Results BIT Data Parametric Data Consumables Config Info S/W Errors Manage Air Vehicle PHM Manage Correlation Area PHM Manage Subsys Area PHM Proc. Priorities PHM Updates A/V Cross Correl Results Test Commands Proc. Priorities PHM Updates MS Cross Correl Results Test Commands PHM Updates Test Commands Manage Subsys PHM Updates Test Commands Subsystems. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 6

Air Vehicle PHM System Architecture Higher-Level PHM -- ICP Subsystem PHM ICP/VMC/Controllers MS Subsystems Manage U&S Subsystem PHM VS Processing Manage MS Subsystem Area PHM Manage MS Subsystem PHM U&S Subsystems Mission Systems AM Manage VS Processing PHM FCS Subsystem Propulsion Subsystems Structural Sensors Manage MS Cross Correlation Area PHM Pilot Interface Mgmt Vehicle Systems AM Manage VS Subsystem Area PHM Manage FCS Subsystem PHM Manage Propulsion Subsystem PHM Manage VS Cross Correlation Area PHM (Propulsion Controllers) Manage Propulsion Area PHM Manage Structures Area PHM Maintainer Interface Mgmt Manage A/V PHM Mission/ Tactical Mgmt Cross Subsystem Mgmt Airframe AM A/C Storage/ Tx Mgmt . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 7

Advanced Techniques Are Applied to JSF Weapon System PHM Solution Performance Monitoring / Trending: PTMS (IPP, Filters, Reservoirs, Coalescer, etc. ) Hydraulic System (Pumps, Filter, Reservoirs, Accumulators) Fuel System (Pumps, Valves, Heat Exchanger) Weapon Bay Door Drive (Pump Speed & Swashplate Angle) Rotary Actuators, EHAs Weapon Racks OBIGGS Filter Cross-Comparison (Redundancy Management): Flight Controls (VMC, Inceptors, EHAs, Sensors) EPS (Degraded modes, Emergency Power) Fuel Probes Auto Calibration / Gain Trending: Radar Displays Fuel Probes Stick & Throttle Enhanced Sensor Technologies: Operational Loads/Usage Monitoring: Engine - FOD Detection, Oil Debris, Structures, Landing / Arresting Gear Oil Condition, Blade Tip Monitoring, Gun, EPS Starter/Generator Vibration Monitoring CSMU (Write Cycles) SDLF - FOD Detection, Oil Debris, Oil Condition, Shaft Alignment / Torque, Clutch Wear / Vibration Off-Board Technologies: Brake Temperature Diagnostic Tools Landing Gear (Strut Servicing, ‘Smart Tire’) Intelligent Help Prognosis Models Capacity Trending: 28 & 270 volt Batteries Cryo Cooling Capacity ESA (loss of Elements) OBIGGS / OBOGS HIPPAG Recharge Rate Information Management: Model-Based Reasoning, Trending, Pattern Recognition (Enhanced Diagnostics, Fault Isolation) Automated Testing: WBDD Actuator Backlash External Fuel Tanks RIOs, VSP Software Nose Wheel Steering Friction Collar CSMU (Periodic Read/Write Testing) Aircraft Wiring PHM Is an Integral Part of Every Facet and Subsystem of the Weapon System. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company

PHM - Enhances FDI • Mechanical Valves is an area of risk for detection and isolation • An example of where the AM can enhance detection/isolation of the Fuel System is shown here in monitoring of the PAO-Fuel HX Check Valve . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company

PHM - Enhances Cross-Correlation Fuel Sub-System ONLY utilizes the purple highlighted sensors for fault isolation of Boost/Transfer Pump. MBR will utilizes ALL the sensors from that whole area of the system to enhance and confirm isolation. Fuel System MBR KB Electrical System MBR KB . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company

Model-Based Reasoning (MBR) Provides a Significant Part of PHM Design Solution MBR Approach Provides Multiple Benefits and Functions: – Intuitive, Multi-Level Modeling – Inherent Cross Checking for False Alarm Mitigation – Multi-Level Correlation for Failure Isolation Advantage Chains of Functions Indicate Functional Flows. – Components Link to the Functions They Support. – Sensors Link to the Functions They Monitor. – Conditions Link to the Functions They Control. Block Diagram Model Legend Condition Function Sensor Component MBR Model . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 11

Example of Model Based Reasoning . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 12

Prognostics • Dictionary definition – “foretelling” or “prophecy” • Our definition – “Using analytical models and historical trends to predict the remaining useful life of components” • Goal of Prognostics on the JSF – Increase safety and mission reliability by predicting failures of critical items with enough time to return to base and perform repair – Decrease collateral damage by predicting catastrophic failures before a failure causes significant damage to aircraft – Decrease logistics costs by allowing greater warning before failure • More efficient maintenance planning • Reduced spares – Decrease unnecessary servicing and replacement • Service aircraft which need servicing instead • Cater to aircraft operating environment and personality Bottom Line: Reduce Operating Costs. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 13

Prognostic Candidates Actuator Leakage and Wear Power and Cooling Turbo Machine Life, Oil Condition, Oil Servicing and Filter Condition Heat Exchangers Engine Generator Oil Level Hydraulic Filters, Pump, and Hydraulic Fluid Level Battery Oxygen Generator Nitrogen Generator and Filter Landing Gear and Arresting Hook Structure fatigue life Rotary Actuator Wear Landing Gear Strut Nose Wheel Stability. DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Pressure and Fluid Level Lockheed Martin Aeronautics Company 14

Prognostic Approaches • Filter Condition (Hydraulic, Oxygen, Nitrogen) – Typical approach trends delta pressure measurement across filter – Filter replaced when predetermined threshold met Filter Delta Pressure For Nearly Constant Flow Critical Band Caution Band Time . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 15

Oxygen Generation • Historical trends of actual performance compared with calculated performance will indicate life Measured Oxygen Concentration Predicted Comparator and Trending Performance Model (Predicted Oxygen Conc) Other Aircraft Parameters Oxygen System Parameters Concentration Measured Critical Band Caution Band Delta Time . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 16

Nose Wheel Shimmy • Nose wheel can vibrate during landing • Divergent vibration is more likely when nose gear free play is high and tire is worn • Two approaches – Monitor and trend free play before taxi – Monitor and trend vibration on landing Shimmy Vibration Measurement Good Nose Gear Force Measured Free Play Landing Gear with Possible Divergent Shimmy . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 17

Some Good Reference Papers • D. G. Bobrow, "Qualitative Reasoning about Physical Systems: an Introduction" – Artificial Intelligence, vol 24 numbers 1 -3, December 1984, ISSN 0004 -3702. • J. De Kleer & J. S. Brown, "A Qualitative Physics based on Confluences“ - Artificial Intelligence, vol 24 numbers 1 -3, December 1984, ISSN 0004 -3702. • K. D. Forbus, "Qualitative Process Theory“ - Artificial Intelligence, vol 24 numbers 13, December 1984, ISSN 0004 -3702. • B. Kuipers, "Commonsense Reasoning about Causality: Deriving Behaviour from Structure“ - Artificial Intelligence, vol 24 numbers 1 -3, December 1984, ISSN 0004 -3702. • J. De Kleer, "How Circuits Work“- Artificial Intelligence, vol 24 numbers 1 -3, December 1984, ISSN 0004 -3702. • R. Davis, "Diagnostic Reasoning Based on Structure and Behaviour“- Artificial Intelligence, vol 24 numbers 1 -3, December 1984, ISSN 0004 -3702. • M. R. Genesereth, "The Use of Design Descriptions in Automated Diagnosis“- Artificial Intelligence, vol 24 numbers 1 -3, December 1984, ISSN 0004 -3702. • A wavelet neural network framework for diagnostics of complex engineered systems Vachtsevanos, G. ; Peng Wang; Echauz, J. Intelligent Control, 2001. (ISIC '01). Proceedings of the 2001 IEEE International Symposium on , 5 -7 Sept. 2001 page(s): 79 – 84 • Prognostics, the real issues involved with predicting life remaining, E ngel, S. J. ; Gilmartin, B. J. ; Bongort, K. ; Hess, A. ; Aerospace Conference Proceedings, 2000 IEEE , Volume: 6 , 18 -25 March 2000, Page(s): 457 -469 vol. 6 . DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Lockheed Martin Aeronautics Company 18