1、_SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising theref
2、rom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions.Copyright 2014 SAE International All rights reserved. No part of this pub
3、lication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-4970
4、(outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/ARP6275AEROSPACERECOMMENDED PRACTICEARP6275Issued 2014-07 Determination of Cost Bene
5、fits from Implementing an Integrated VehicleHealth Management System RATIONALEThis SAE Aerospace Recommended Practice (ARP) provides insight into the factors to be considered for not only generating a cost benefit analysis but also the justification for implementing an integrated health management s
6、ystem to an air vehicle. With the considerable advancement of prognostics and health management (PHM) tools and capabilities in the past 10 years, more and more operators and fleet managers are asking for ways in which the overall value proposition of installing such a system, be it on in-service eq
7、uipment or still-in-design systems, can be determined. TABLE OF CONTENTS 1. SCOPE 41.1 Purpose . 41.2 Approach . 42. REFERENCES 42.1 Applicable Documents 42.1.1 SAE Publications . 42.1.2 Other Documents 53. ACRONYMS . 54. INTRODUCTION. 64.1 Motivation for Implementing an Integrated Health Management
8、 System . 64.2 Fundamental Considerations Preceding the Cost Benefit Analysis . 75. FACTORS INFLUENCING COST BENEFIT STUDIES AND ANALYSES 85.1 PHM System Complexity 85.2 Usage: The Considerations and Differences between Categories of Operators . 85.3 Legacy versus New Platforms 95.4 Impact on Design
9、 105.5 Performance versus Reliability or Sustainment 105.6 Cost Savings versus Cost Avoidance . 116. COSTS FOR CONSIDERATION IN AN AIRCRAFT PHM COST BENEFIT STUDY 116.1 Impact on Cost and Weight . 116.2 PHM System Scope and Complexity 136.2.1 Data Generation and Acquisition 136.2.2 Data Recording .
10、136.2.3 Data Format Compatibility 136.2.4 On-board versus Off-board. 146.2.5 Vehicle/Platform Integration 146.2.6 Communications (including Satellite and Other Relay Provisions) 146.2.7 Ground Station 14SAE INTERNATIONAL ARP6275 Page 2 of 34 6.2.8 Data Storage and Archiving 146.2.9 Information Deliv
11、ery 156.2.10 Data Security . 156.2.11 Software (including Software Maintenance) . 156.2.12 System Availability 156.2.13 Technical Support and Training for Users 156.2.14 Continuous Upgrades . 156.3 Development Costs . 166.3.1 Requirements Definition 166.4 Build and Qualification Costs 176.5 Producti
12、on Costs . 176.6 Operational Costs . 176.6.1 Labor for Data Handling, Analysis, Storage, Back-Up and Transmission 176.6.2 Data Transmission and Storage Costs . 176.6.3 Additional Fuel Costs 186.6.4 Unnecessary Maintenance Due to PHM System “False Alarms” . 186.7 PHM System Sustainment Costs 186.7.1
13、PHM System Training . 186.7.2 PHM System Upgrades 196.7.3 PHM System Maintenance . 196.8 Aftermarket Impact on Costs 196.8.1 Increased On-wing Component Life . 196.8.2 Removing Components Before They Actually Fail . 197. BENEFITS FOR CONSIDERATION IN AN AIR VEHICLE PHM COST BENEFIT STUDY . 207.1 Fue
14、l Savings . 207.1.1 Fewer Mission Aborts, Air turn-backs, Diversions 207.1.2 Increased Propulsive Efficiency and Reduced Platform Drag 207.2 Increased Accuracy in Identifying Faulty Components. 207.3 Trending of Performance Degradation and Early Corrective Action. . 217.4 Business Benefits 217.4.1 W
15、arranty/Guarantee Mitigation . 217.4.2 Reduced Support Services Costs . 217.4.3 Life Limited Parts 217.4.4 Increased Residual Value . 227.5 Reduced Weight of Airframe Systems through Reduced Redundancy and Conservatism . 227.6 Maintenance Savings 227.6.1 Reduced Line Maintenance Labor-Hours/Staffing
16、 227.6.2 Reduced Shop Maintenance Labor-Hours/Staffing 227.6.3 Reduced Number of LRUs Returned for Bench Check/Overhaul and Reduced “Back Shop”Labor-Hours/Staffing . 237.7 Operational Savings 237.7.1 Fewer Delays, Diversions, Air-Turnbacks and Unplanned Component Removals 237.7.2 Greater Platform Av
17、ailability . 237.8 Savings from Reduced Capital Investments . 237.8.1 Reduced Spare Equipment, Parts and Material Stocks . 247.8.2 Reduced Maintenance Facilities and Equipment at All Levels . 247.8.3 Reduced Investment in Production Equipment and Facilities due to Lower Demand for Vehicles,Spares, a
18、nd Material . 247.9 Other Miscellaneous Costs. 247.9.1 Marginally Reduced Dependence on Strategic Materials and Obsolete Components 248. CHALLENGES ASSOCIATED WITH COMPLETING A COST BENEFIT STUDY 258.1 Scope of Cost Benefit Study . 258.2 Data Availability . 258.3 Qualitative Values . 258.4 Desired F
19、idelity . 268.5 Perception of PHM System Value . 268.6 Is a Cost Benefit Study Really Necessary? 268.7 PHM is Too Good to Be True 27SAE INTERNATIONAL ARP6275 Page 3 of 34 9. EXAMPLES OF PHM IMPLEMENTATION AND COST ANALYSIS MODELS 279.1 Implementation of CBM+ on U.S. Army Helicopters . 279.2 IVHM Dev
20、elopment on the Gulfstream G650 Aircraft; Aircraft Health and Trend MonitoringSystem (AHTMS) 289.2.1 Deriving the Business Case 309.3 IVHM Development on the Embraer E-Jets 319.3.1 Business Case 329.4 Integration of a HM model (Reference 2) . 3310. SUMMARY 3311. NOTES 34SAE INTERNATIONAL ARP6275 Pag
21、e 4 of 34 1. SCOPE This ARP provides insights on how to perform a cost benefit analysis (CBA) to determine the return on investment that would result from implementing an integrated Health Management (HM) system on an air vehicle. The word “integrated” refers to the combination or “roll up” of sub-s
22、ystems health management tools to create a platform centric system. The document describes the complexity of features that can be considered in the analysis, the different tools and approaches for conducting a CBA and differentiates between military and commercial applications. This document is inte
23、nded to help those who might not necessarily have a deep technical understanding or familiarity with HM systems but want to either quantify or understand the economic benefits (i.e., the value proposition) that a HM system could provide. Prognostics is a capability within some HM systems that provid
24、es an estimation of remaining useful life (RUL) or time to failure and so Prognostic Health Management (PHM) is used where this predictive element exists. IVHM refers to an integrated vehicle level system deployed on a fleet of platforms and might, but not necessarily, include predictive elements.1.
25、1 Purpose This ARP is not a standard or legal document because the approaches towards the end objective are many and varied. The document has been compiled to help the increasing number of people who want to compute a HM CBA prior to implementing such a system on a platform. 1.2 Approach The approac
26、h taken was to identify the parameters that were relevant for consideration in a cost benefit analysis so that the boundaries of a specific problem could be defined from the outset. Several recent and worthy papers presented at conferences on the subject matter were studied and as much information a
27、s possible was obtained from the aerospace manufacturers and the DoD to identify tools and techniques that they might have used to good effect. The various methods were assessed by the SAE HM-1 Technical Committee team for their application to specific scenarios (e.g., military or commercial operati
28、on, legacy or new engines) and the parameters utilized by each scenario. The end result is a document that offers the reader various solution paths so that the one most appropriate to the specific situation can be used or adapted. 2. REFERENCES 2.1 Applicable Documents The following publications for
29、m a part of this document to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date of the purchase order. In the event of conflict between the text of this document and references cited herei
30、n, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 2.1.1 SAE Publications Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (i
31、nside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.Jennions, I.K., “Integrated Vehicle Health Management: Perspectives on an Emerging Field,“ SAE International, Warrendale, PA, ISBN 978-0-7680-6432-2, 2011, doi:10.4271/R-405. Jennions, I.K., “Integrated Vehicle Health Management: Busin
32、ess Case Theory and Practice,“ SAE International, Warrendale, PA, ISBN 978-0-7680-7645-5, 2012, doi:10.4271/R-414. AIR1871, Lessons Learned from Developing, Implementing, and Operating a Health Management System for Propulsion and Drive Train Systems ARP1587, Aircraft Gas Turbine Engine Health Manag
33、ement System Guide AIR4061, Guidelines for Integrating Typical Engine Health Management Functions Within Aircraft Systems AIR4175, A Guide to the Development of a Ground Station for Engine Condition Monitoring SAE INTERNATIONAL ARP6275 Page 5 of 34 ARP4176, Determination of Costs and Benefits from I
34、mplementing an Engine Health Management System AIR5871, Prognostics for Gas Turbine Engines 2.1.2 Other Documents Reference 1: Army Implementation of CBM: 2012 Update, Presented by Chris Smith, Army Aviation if the time taken for the landing gear to retract is increasing, the interacting systems can
35、 be monitored to accurately diagnose the root cause. Similarly, slowly increasing asymmetry over time of flight control surfaces such as flaps, ailerons and spoilers and rudder positions is important to know not only from a flying perspective but also a desire for fuel efficiency, especially on long
36、-haul flights. In the case of control surface asymmetry, airline operators are interested to the extent that they will monitor fuel consumption on a tail number basis and perform checks on the control surface positions of the planes with the worst fuel consumption because they see the need to do so;
37、 they are practicing Condition-based maintenance (CBM) based on fuel consumption changes. The cost benefit analysis of a PHM system is thus highly dependent on the requirements of the end customer yet, up to now, HM systems in general have been largely provided by the airplane manufacturers who have
38、 typically pre-determined the capabilities. However, ever changing priorities, such as an increased interest in fuel savings by the operators, is likely to introduce additional, new features or new functionalities to meet the operators defined needs. An example would be more sophisticated monitoring
39、 of control surface positions, especially any synchronization issues when they are being deployed. While the system would be operating satisfactorily, and safely, and meeting operating specifications, it might not be optimized for fuel efficiency. The interface to the aircraft will also need some de
40、gree of customization. This includes the degree of “on-board” analysis of the data and real-time action compared with downloading data at some later date and processing it in a ground software station. Thus, the user needs to determine, at the outset, the desired capabilities of a PHM system and bui
41、ld a CBA from that base-line. If the specific needs are not able to be precisely defined, then several scenarios could be created and a CBA computed for each, which would reveal the trade-offs between system complexity and return on investment. In the propulsion arena, which has historically tended
42、to be the lead sub-system for HM, mandated vibration monitoring resulted in vibration monitoring systems installed on engines and aircraft in the seventies. In more recent times ETOPS (extended twin engine operations), drove the need for an EHM system in commercial fixed wing operations, especially
43、those across water, as was also the case for rotorcraft operating in support of oil rigs in the North Sea. For airframe systems, the drivers are not so clear cut and there are no mandates to equip a fleet with a HM system. Instead, once the HM capabilities are visible and demonstrated to the airplan
44、e OEMs or the operators, then business cases start to be generated because the capability has generated new, perceived needs. In other words, capabilities sometimes generate needs as opposed to needs generating the development of new capabilities. However, some regulation-driven PHM functionality do
45、es exist today on airframes. For example, for emergency battery backup systems, there is a requirement to show the state of charge (SoC) indication before a flight so that the flight crew can be assured that the battery can be used during an emergency to restart the engine or to provide power for ot
46、her essential electrical functions. This is an example of a PHM system specific to the airframe. 5.2 Usage: The Considerations and Differences between Categories of OperatorsIt is well appreciated that military and commercial aircraft operate in starkly contrasting flight regimes and this makes a la
47、rge difference when considering the cost benefit approach to take. First and foremost, commercial operators fly similar operations every day, whereas military aircraft are typically conducting flying training and preparatory operational missions on a normal basis until a major exercise or combat/war
48、 scenario is brought to bear, at which time the intensity of operations increases significantly for an unknown period of time (could be several days to several years). Generally, military airplanes fly into and out of the same base on a daily basis whereas commercial planes are typically crossing the country or world where maintenance facilities at non-hub locations are
