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/AS6021AEROSPACESTANDARDAS6021Issued 2014-01 AS6021 Aerospace Fiber Optic Cable Assem
5、bly Drawing Specification RATIONALEAS6021 is intended to provide guidance to harmonize the content of aerospace fiber optic cable assembly engineering drawings. AS5675 and AS6021 together comprise part of an overall document set to address aerospace fiber optic cable assembly specification, quality
6、assurance inspection, and performance testing.TABLE OF CONTENTS 1. SCOPE 31.1 Purpose . 31.2 Field of Application 32. REFERENCES 32.1 Applicable Documents 32.1.1 SAE Publications . 32.1.2 U.S. Government Publications 32.1.3 Applicable References 42.1.4 Order of Precedence . 42.2 Definitions . 43. AE
7、ROSPACE FIBER OPTIC CABLE ASSEMBLY SPECIFICATION REQUIREMENTS 83.1 Background . 83.2 Application Areas 83.3 Utilization . 84. COMPONENTS AND MATERIALS 94.1 Fiber Specification. 94.2 Fiber Cable Specification 94.3 Terminus Specification 104.4 Connector Specification 104.5 Accessory Specification 114.
8、6 Protective Cap Specification . 114.7 Cable Assembly Specification . 114.7.1 Optical Requirements . 114.7.2 Endface Coating Requirements 114.7.3 Pinout Table/Connection Diagram 114.7.4 Clocking Configuration 114.7.5 Cable Assembly Length 124.7.6 Epoxy Specification . 124.7.7 Marking and Labeling Sp
9、ecification 124.7.8 Non-Destructive Pull Test . 12SAE INTERNATIONAL AS6021 Page 2 of 22 5. MATERIAL PROCESSING . 125.1 Terminus Processing (if applicable) 125.2 Connector Processing (if applicable) 125.3 Cable Processing 125.4 Accessory Processing . 125.5 Non-Metallic Materials Processing (if applic
10、able) . 125.6 Epoxy Storage, Handling, and Shelf Life 126. TERMINATION PROCESS . 126.1 Fiber/Cable Preparation (i.e., strip lengths) 126.2 Epoxy Processing . 136.3 Post Epoxy Cure Cleaving 136.4 Polishing Procedure 136.5 Cleaning Procedure 136.6 Endface Geometry Measurement . 136.7 Endface Inspectio
11、n Criteria . 136.8 Optical Testing 137. MULTICHANNEL CONNECTOR CABLE ASSEMBLY COMPLETION . 137.1 Populating a Multichannel Connector . 137.2 Accessories . 137.3 Mounting Hardware . 137.4 Heatshrink / Boot Material . 137.5 Cable Protection 147.6 Potting / Molding . 147.7 Marking / Labeling Materials
12、. 147.8 Marking / Labeling Locations 147.9 Special Tool . 148. ACCEPTANCE TEST COMPLIANCE 148.1 First Article Testing . 148.2 Endface Inspection . 148.3 Insertion Loss Testing . 148.4 Return Loss Testing (if applicable) . 148.5 Non-Destructive Pull Test (if applicable) . 148.6 Terminus, Connector, a
13、nd Protective Cap Cleanliness 148.7 Thermal Workmanship (space applications only) . 158.8 Decontamination (space applications only) 158.9 Environmental Stress Screening (ESS) (if applicable for production testing) 159. QUALIFICATION. 1510. DOCUMENTATION 1511. QUALITY ASSURANCE . 1512. PACKAGING AND
14、SHIPPING 1513. STORAGE . 1514. NOTES 15APPENDIX A CABLE ASSEMBLY LENGTH 16APPENDIX B CABLE ASSEMBLY OUTGASSING . 17APPENDIX C MEASUREMENT METHODS . 18APPENDIX D REQUIREMENTS CHECKLIST 19APPENDIX E CABLE ASSEMBLY TECHNICAL DRAWING EXAMPLE 22SAE INTERNATIONAL AS6021 Page 3 of 22 1. SCOPE This SAE Aero
15、space Standard (AS) defines the items that shall be considered when creating a fiber optic cable assembly specification and source control drawing intended for installation on aerospace platforms. 1.1 Purpose The purpose of this document is to provide guidance on criteria that shall be considered wh
16、en specifying an aerospace fiber optic cable assembly. Users of this document are cautioned to not over-specify inspection and test requirements, as this may adversely affect price and/or lead time. It is helpful to cite widely recognized standards as an aid to provide specific requirements.1.2 Fiel
17、d of Application This document defines the required content of a comprehensive aerospace fiber optic cable assembly engineering specification (or source control document) and checklist. The specified requirements are applicable to end users, system integrators, subsystem suppliers and component vend
18、ors.2. REFERENCES 2.1 Applicable Documents The following publications form 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
19、 of conflict between the text of this document and references cited herein, 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
20、, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.ARP5061 Guidelines for Testing and Support of Aerospace, Fiber Optic, Inter-Connect Systems AS5382 Aerospace Cable, Fiber Optic AS5590 Connectors, Fiber Optic, Ad
21、vanced, Circular or Rectangular, Plug and Receptacle, Environment Resistant, Removable Termini/Contacts, General Specification For AS5675 Characterization and Requirements for New Aerospace Fiber Optic Cable Assemblies - Jumpers, End Face Geometry, Link Loss Measurement, and Inspection AIR6031 Fiber
22、 Optic Cleaning 2.1.2 U.S. Government Publications Available from DLA Document Services, Building 4/D, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Tel: 215-697-6396, http:/quicksearch.dla.mil/.MIL-PRF-29504 Fiber Optic Terminus MIL-PRF-49291 Optical Fiber MIL-PRF-64266 Fiber Optic Connector MIL
23、-PRF-85045 Fiber Optic Cable MIL-STD-1678 Fiber Optic Cable Systems Requirements and Measurements SAE INTERNATIONAL AS6021 Page 4 of 22 2.1.3 Applicable References TIA/EIA-440 Fiber Optic Terminology ANSI/NCSL Z540.3 Requirements for the Calibration of Measuring and Test EquipmentASTM E595 Standard
24、Test Method for Total Mass Loss and Collected Volatile Condensable Materials from Outgassing in a Vacuum Environment 2.1.4 Order of Precedence In the event of a conflict between the text of this document and the references cited herein (except for related associated detail specifications, specificat
25、ion sheets, or military standards), the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 2.2 Definitions ATTENUATION: Attenuation in fiber optics, also known as transmission loss, is t
26、he reduction in average optical power (or intensity of the light beam (or signal) with respect to distance traveled through the fiber or fiber optic cable assembly/plant. Attenuation in general is expressed in dB without a negative sign. ACCESSORY: Connector components such as backshells, strain rel
27、ief, extenders, and adapters. ACCESSORY CLOCKING: The angular relationship in degrees between the master connector key or keyway and the accessory. BACKSHELL: The housing accessory on the back of a multichannel fiber optic connector that covers the area where the terminated fiber optic cables exit t
28、he back end of the connector. BANDWIDTH: Measure of information carrying capacity; the greater the bandwidth, the greater the information carrying capacity.BANDWIDTH-DISTANCE PRODUCT: A reference value, normalized to 1 km, used to predict the bandwidth capacity of other fiber lengths or concatenated
29、 fiber lengths over a specific distance. The bandwidth-distance product is determined by the physical construction of the fiber or cable and is expressed in frequency distance (usually as MHzkm or GHzkm). Bandwidth-distance product is given under specified launching and cabling conditions at a speci
30、fic wavelength and is equal to the product of the fibers length and the 3-dB bandwidth of the optical signal (or the maximum data rate of the optical signal).The bandwidth-distance product is typically limited by acceptable bit error rate. BEND DIAMETER, MINIMUM, SHORT TERM: The short term bend diam
31、eter applies during handling, packing, unpacking, and installing. BEND DIAMETER, MINIMUM, LONG TERM: The long term bend diameter applies to the completed installation. BEND LOSS: The result of macrobends (curvature of fiber) or microbends (small distortions in the fiber) producing increased attenuat
32、ion by coupling light energy from the fiber core to the fiber cladding. BEND RADIUS: Fiber optic cable minimum bend radius (specified by the cable manufacturer or aerospace entity responsible for the performance, reliability, and durability of the installed cable) defines the minimum radius the cabl
33、e can be safely bent without kinking it, damaging it, degrading its optical performance or shortening its short-term life (during packaging, shipping, and installation) and long-term operational life (while installed on the aerospace platform). BREAKOUT LENGTH: Distance from where discrete fibers br
34、eak out/branch out/fan out from the fiber bundle or ribbon. SAE INTERNATIONAL AS6021 Page 5 of 22 BUFFER COATING: Protective material that covers and protects a fiber. (No optical function.) CABLE ASSEMBLY: A cable, consisting of an optical fiber surrounded by layers of plastic and strength member m
35、aterial, that is terminated with a fiber optic terminus or connector at each end. The cable assembly is the optical interconnect medium for transmitting digital and/or analog communication signals using light rather than electricity. CABLE PRECONDITIONING: A process whereby a fiber optic cable is re
36、moved from its spool and placed in temperature controlled chamber to remove intrinsic stress in the extruded cable jacket and/or inner tubing and/or the entire cable construction materials which in turn prevents uncontrolled cable shrinkage in the application environment. CABLE STRENGTH MEMBER: A co
37、mponent in the cable that increases the cables strength, protects the optical fibers in the cable from strain and, when stranded in opposing lays, assists to minimize microbending. When terminating a connector/terminus onto the end of a fiber optic cable, the strength member is secured to the connec
38、tor/terminus. The intent is for a force caused by a pull on the cable to be placed on the strength member and not on the fiber inside the connector/terminus.CALIBRATION: Calibration is the comparison of a measurement system or device of unverified accuracy with a measurement system of known and grea
39、ter accuracy, over the dynamic range of use, to detect any deviation (measurement uncertainty) from required performance specifications of the unverified measurement system or device over its dynamic range of use. CALIBRATION TRACEABILITY: The calibration process includes the traceability of the mea
40、surement uncertainty through an unbroken calibration chain to the SI unit standards maintained by a nations National Measurement Institute (NMI).CENTRIFUGE: A centrifuge is a piece of equipment that puts an object (such as uncured epoxy in a tube or syringe) in rotation around a fixed axis, applying
41、 a force perpendicular to the axis. The centrifuge works using the sedimentation principle, in which the centripetal acceleration causes more dense substances to separate out along the radial direction (the bottom of the tube). By the same token, lighter objects (such as air bubbles) will tend to mo
42、ve to the top of the tube. CHAFING: Repeated motions between cabling components between cabling and equipment, between cabling and structure that result in wear causing mechanical failure and/or degraded or complete optical performance failure. Wear is the result of excessive rubbing, twisting, or b
43、ending. CLADDING: That dielectric material surrounding an optical fiber core that has a lower refractive index than that of the fiber core. CLADDING DIAMETER: The outside diameter of the cladding region. CLAMPING LOSS: Bend loss induced by clamping the cable assembly on the aerospace platform. CLEAV
44、ING: Cleaving entails inducing a defect on the outside diameter of the fiber with a diamond scribe or equivalent. To activate the cleaving process, after a mechanical defect is scribed on the outer surface of the fiber, the fiber is stressed longitudinally (tensile loading), which causes a crack to
45、propagate across the fiber diameter. If proper tension is applied to the fiber as the nick is made, or immediately afterward, the fracture will propagate in a controlled fashion, creating the desired cleaved fiber endface. Rough cleaving is usually performed prior to fiber optic terminus polishing.
46、COEFFICIENT OF THERMAL EXPANSION (CTE): The coefficient of thermal expansion describes how the size of an object changes with a change in temperature. Specifically, CTE defines the fractional change in volume per degree change in temperature at a constant pressure. CONNECTOR: Hardware installed on f
47、iber optic cable ends to connect fiber optic cables to a device or another connector. Fiber optic connectors enable repeated mating and enable efficient coupling of optical power between two optical fibers or two groups of optical fibers. CONTAMINANT: An unwanted constituent on the surface of a ferr
48、ule and fiber endface that requires removal. CORE: The central region of an optical fiber with higher refractive index than that of the cladding, within which most of the optical power is transmitted. SAE INTERNATIONAL AS6021 Page 6 of 22 CORE/CLAD CONCENTRICITY (or CORE-TO-CLADDING OFFSET): Core/cl
49、ad concentricity defines how well the core is centered in the cladding glass region. Tighter core/clad concentricity tolerances help ensure that the fiber core is centered in relation to the cladding. CORE DIAMETER: The diameter of the circle defining the core center. CUTOFF WAVELENGTH: The shortest wavelength for which an optical fiber can only support the propagation of a single transverse mode. DECONTAMINATION: Involves vacuum bake o