1、 STRATEGIES TO ADDRESS ELECTRONICCOMPONENT OBSOLESCENCE IN COMMERCIALAIRCRAFTARINC REPORT 662PUBLISHED: APRIL 7, 2000AN DOCUMENTPrepared byAIRLINES ELECTRONIC ENGINEERING COMMITTEEPublished byAERONAUTICAL RADIO, INC.2551 RIVA ROAD, ANNAPOLIS, MARYLAND 21401This document is based on material submitte
2、d by variousparticipants during the drafting process. Neither AEEC norARINC has made any determination whether these materials couldbe subject to valid claims of patent, copyright or other proprietaryrights by third parties, and no representation or warranty, expressor implied, is made in this regar
3、d. Any use of or reliance on thisdocument shall constitute an acceptance thereof “as is” and besubject to this disclaimer.Copyright 2000AERONAUTICAL RADIO, INC.2551 Riva RoadAnnapolis, Maryland 21401-7465 USAARINC REPORT 662STRATEGIES TO ADDRESS ELECTRONIC COMPONENT OBSOLESCENCE IN COMMERCIAL AIRCRA
4、FTPublished: April 7, 2000Prepared by the Airlines Electronic Engineering CommitteeReport 662 Adopted by the Airlines Electronic Engineering Committee: February 15, 2000Report 662 Adopted by the Industry April 7, 2000iiFOREWORDActivities of AERONAUTICAL RADIO, INC. (ARINC)and thePurpose of ARINC Rep
5、orts for Avionics MaintenanceAeronautical Radio, Inc. is a corporation in which the United States scheduled airlines are theprincipal stockholders. Other stockholders include a variety of other air transport companies, aircraftmanufacturers and foreign flag airlines.Activities of ARINC include the o
6、peration of an extensive system of domestic and overseasaeronautical land radio stations, the fulfillment of systems requirements to accomplish ground and airbornecompatibility, the allocation and assignment of frequencies to meet those needs, the coordination incident tostandard airborne communicat
7、ions and electronics systems and the exchange of technical information.ARINC sponsors the Avionics Maintenance Conference (AMC), composed of airline maintenance personnel.It is an informal industry organization serving the needs of the air transport industry in matters of avionicsmaintenance. Its ob
8、jectives are promotion of improved avionics systems and equipment reliability andperformance. It is the medium of exchange of information and ideas between and among users, repair shops,installers, suppliers, manufacturers, and designers of avionics systems, equipment, and components as aprofessiona
9、l approach to maintainability and maintenance practices.AMC objectives are effected through industry conferences and informal task groups who work onproblems of mutual industry concern. The services are administered by a Steering Group (composed of airtransport operator personnel in charge of avioni
10、cs line maintenance, overhaul shops, and maintenanceengineering) and a Secretariat provided by ARINC.Traditionally, ARINC “Gray Cover” documents have originated within the Airlines ElectronicEngineering Committee (AEEC), another standing committee of ARINC, composed of avionics developmentengineerin
11、g personnel. AEEC is functionally oriented toward formulation of standards for air transportavionics equipment. Although AMC is primarily a forum for the informal exchange of logistical information,both AEEC and AMC realize that only through AMC effort can needed guidance documents concerningmainten
12、ance engineering be prepared because of the increased demand on AEEC for more and more newARINC airborne hardware specifications.It is desirable to reference certain general ARINC Specifications or Reports which are applicableto more than one type of equipment. These general Specifications or Report
13、s may be considered assupplementary to the Equipment Characteristics in which they are referenced. They are intended to set forththe desires of the airlines pertaining to components and general design, construction and test criteria, in orderto insure satisfactory operation and the necessary interch
14、angeability in airline service. The release of aSpecification or Equipment Characteristic should not be construed to obligate ARINC or any airline insofar asthe purchase of any components or equipment is concerned.An ARINC Report (Specification or Characteristic) has a twofold purpose which is:(1) T
15、o indicate to the prospective manufacturers of airline electronic equipment the considered opinionof the airline technical people coordinated on an industry basis concerning requisites of newequipment, and(2) To channel new equipment designed in a direction which can result in the maximum possiblest
16、andardization of those physical and electrical characteristics which influence interchangeability ofequipment without seriously hampering engineering initiative.ARINC REPORT 662TABLES OF CONTENTSITEM SUBJECT PAGEiii1 INTRODUCTION 11.1 Purpose and Goals 11.2 Background 12.0 DESIGN STRATEGIES 22.1 Des
17、ign 22.1.1 Design Guidelines 22.1.2 Select Components to Minimize Obsolescence Risk 32.1.3 Shop Discardable Units 32.1.4 Design Review 32.2 Obsolescence Resolution 32.2.1 Obsolescence Identification 32.2.2 Resolution Options 32.3 Operational Support 42.4 Level 3 Maintenance Considerations 42.5 Modif
18、y Equipment Operating Procedures 42.6 Cooperative Activities 4ATTACHMENTS1 Glossary 52 Example Prediction Process 6ARINC REPORT 662 Page 11.0 INTRODUCTION1.1 Purpose and GoalsThe purpose of this document is to establish guidelinesthat should be observed during initial design, productionand maintenan
19、ce of avionics LRUs, and to present short-term and long-term strategies to minimize the costs andimpacts associated with decreasing availability ofelectronic components.The aerospace industry depends on electroniccomponents, but can no longer assume long-termavailability. There is a need to design,
20、produce andsupport avionics with components produced forconsumer electronics that are characterized by short lifecycles.The goals of this report are to: Provide guidelines for avionics designs that will betolerant of component obsolescence. Identify cost effective methods for resolvingcomponent obso
21、lescence issues. Recommend the use of standardized components foravionics. Facilitate information exchange, e.g., obsolescencesolutions, databases, etc. Establish maintenance operation and supportprocesses to address obsolescence.Refer to the glossary in Attachment 1 for definitions andterms.1.2 Bac
22、kgroundThe importance of electronics in commercial airplanes hasgrown steadily since the beginning of the commercial jetage. Although electronic components and systemsconstitute a relatively small part of the total cost of theairplane, they are ubiquitous. Electronic components arepart of almost eve
23、ry airplane system, including those thatare primarily mechanical, hydraulic, and pneumatic.Electronic components refers to integrated circuits,resistors, diodes, transistors, and other electronic items inindividual packages, i.e., electronic components are to beconsidered the same as piece parts. Hi
24、gher assembly-levelitems, such as line replaceable units (LRUs), also arecalled electronic components in some contexts, but thatterminology is not used here.The commercial jet airplane industry has grown in parallelwith the solid state electronics industry. Both were“invented” in the 1940s, saw thei
25、r first significantcommercial applications in the late 1950s, and have grownto maturity since then. Commercial airplane equipmentmanufacturers, airframe manufacturers, and operators, liketheir military counterparts, depended in the early days ona well-developed military electronic components andspec
26、ifications infrastructure to assure long-termavailability and reliability of components that met theirneeds. This was made possible by the fact that themilitary market sector, which was about 25% of the total,was responsible for a good deal of the device innovation,and therefore “owned” many device
27、designs. As a result,military and commercial aerospace electronic equipmentdesign, manufacturing, procurement, operation,maintenance, and support decisions have been based ontwo assumptions.1. The supply of electronic components specified tooperate in aerospace environments is unlimited; and2. The c
28、omponent designs will remain stable for longperiods of time.These assumptions are no longer true.The major markets for electronic components arecomputers, consumer electronics, and others, which donot require components with the demandingspecifications and long production life cycles ofaerospace pro
29、ducts; so the availability of componentsspecified for aerospace applications is decreasing. Since1992, at least 12 major manufacturers of electroniccomponents, including Motorola, Intel, and Philips, haveexited the military market. For the first time in the historyof solid state electronics, the aer
30、ospace industry has nobroad-based access to a vertical supply chain forelectronic components.The life cycles of all integrated circuit technologies areshrinking, almost to the point where the term componenttechnology life cycle is meaningless. This is especiallytrue in view of the fact that even “st
31、able” componentdesigns are modified constantly in order to reduce cost,improve yields, and enhance performance. These changesare evaluated and characterized for high-volumeapplications, such as computers, but the applications oflow volume users such as aerospace are rarelyconsidered. A typical comme
32、rcial jetliner will exist throughmany generations of electronic component designs duringits lifetime. Furthermore, while the “military system”assured that components with the same part numberwould have identical specifications regardless of whomanufactured them, this is not true of non-militarycompo
33、nents. This impacts both new equipment designsand component replacements in existing equipment.ARINC REPORT 662 Page 22.0 DESIGN STRATEGIES2.1 DesignA significant mismatch in life cycles exists between thecomponent part supply (typically 2-5 years) and theaerospace industry where 20-40 years of supp
34、ort arerequired. As a result, the designer should evaluate thetechnologies, packages, vendors, processes, etc.throughout the design process.The design phase of a products life cycle is also the timewhen the greatest impact on product cost is made. Alldesigns contain electronic parts that will eventu
35、allybecome obsolete. The consideration of obsolescencemust be made at the same time that the designer isexpected to reduce costs, lower design cycle time, andincrease quality.A basic “design for obsolescence minimization” flowchart is shown below.2.1.1 Design GuidelinesThere are a number of key area
36、s that must be consideredearly in the design phase in order to provide the mostbenefit. These include:Develop a Life Cycle Plan for each function early in thedesign phase- A formal process should be developed and employedto establish Life Cycle Plans as an integral part of thedesign process.- Life C
37、ycle Plans should include contingency plansfor especially critical components such as those withlimited supply issues or software dependentapplications. Examples of contingency plans include:- Multiple sources- Allowance for varying voltage sources (or otherchangeable parameters) in the design- Futu
38、re packaging and technologies- Special production stock- Develop strategies to align life cycles takingadvantage of future component technologies andproduct update opportunities.- Include migration plans for expected technology orpackaging advances (ASICs/PLDs, memories,Microprocessors, functional m
39、odules, etc.).- Functionality must be supported, not necessarily thehardware and software configuration.Modular LRU design at a functional level- Define avionics functionality early that will allow useof common component parts.- Avoid use of specially selected components from ageneric part number.-
40、Partition design at a functional level (without anysoftware impact) to facilitate reuse of commonhardware functions, supportability, and insertion offuture component technologies.- VHDL models should be used to define thepartitioned functions as well as for programmabledevices, e.g., FPGAs, PLDs, AS
41、ICs, etc.Combine obsolescence management with planned productimprovements- The life cycle plan should include expected futurecomponents and technologies.This is especially important for memory devices,microprocessor devices, COTS assemblies, etc. andcomponents with shorter life cycles or limited sup
42、plysources.- Planned product improvement should be coordinatedwith other product changes and enhancements.- System simulation (virtual prototyping) can be usedto develop future improvements and validatecompatibility.Provide Obsolescence Information for Designers- The component information system sho
43、uld supplythe designer with information related to componentselection to minimize the impact of obsolescenceincluding part technologies, future packagingexpectations, life cycle information, longevity of part,and cost derived from commodity roadmaps.- Predictive obsolescence information must beinclu
44、ded in the component part database.- Purchasing and Component Specialists must workclosely with Designers to minimize the impact ofobsolescence.- Utilize component selection strategies as described insection 2.1.2Consider certification and recertification impact- Partition hardware and software to m
45、inimizerecertification efforts and costs.- Recertification issues need to be considered at threelevels:- DesignConceptLife CyclePlanComponentSelectionDesignReviewOperationalSupportManufacturingPlanned Prod.ImprovementComponentInfo SystemCommodityRoadmapsObsolescenceForecast InfoObsolescenceResolutio
46、nMetricsARINC REPORT 662 Page 32.0 STRATEGIES TO ADDRESS OBSOLESCENCE (contd)-FAA/JAA Requirements-OEM/Airframe requirements-Supplier requirements- Maintain form/fit/function equivalence to simplify therecertification processes and approvals for redesign.- Maintain an up to date list of authorized s
47、ubstitutesin accordance with the electronic parts substitutionstandards of FAA/JAA.2.1.2 Select Components to Minimize Obsolescence RiskSelect parts from a preferred parts list. The list should limitthe proliferation of parts and should consider thefollowing parameters: Component is a multi-user par
48、t. Component is not too application or user specific. Component is used in large volume by otherproducts. Component technology is well known and up-to-date. Component is recommended by the componentmanufacturer for design. Component has multiple manufacturers. Component life cycle and availability d
49、ata is known. Component has a defined migration path to futuretechnology or supply sources.To ensure the above criteria are met, communication withthe component manufacturer and other users isnecessary. Coordinated efforts by OEMs are taking placewith a goal to produce an industry standard PPL (e.g.,STACK International).2.1.3 Shop Discardable UnitsThe consumer electronics industry has adopted thepractice whereby failed subassemblies are usually notrepaired, but discarded. This practice cannot (yet) beapplied to avionics LRUs because the installed SRUs arenormally too
