ARINC 624

Pumose of this Document

This document sets forth a general philosophy, basic guidance,and certain specific recommendations for the design and use of anonboard maintenance system (OMS).

The OMS described incorporates the traditional areas of failuremonitoring and fault detection, BITE, BITE access, and anairplane condition monitoring system (ACMS), formerly known asaircraft integrated data system (AIDS). It further describes thecapability to provide onboard maintenance documentation (OMD) andthe requirement for total integration of these functions. Itdescribes the requirements for all elements of the OMS, including acentral maintenance computer (or CMC function) and all the membersystems which interface with it.

This document is intended to provide a better mutualunderstanding among the designers and users of the specified OMSincluding all its member systems, with a view toward achieving anoptimum balance between critical factors such as BITEeffectiveness, operator interface simplicity, cost, and systemcomplexity. A description of one possible architecture for an OMSis also included in the document. This description is not intendedto delineate the design for an OMS, but to provide an example forunderstanding the requirements for such a system.

This document discusses the role of an OMS in the airlines’maintenance concept and -the fault detection and BITEcharacteristics desirable in all avionics equipment to· support thebroader goals of an OMS. Beyond the guidance applicable to BITE,this document provides specific guidance for the design of an OMSwhich provides for:

– A standardized, English-language-based user interface forperforming all BITE tests and line maintenance functions on theairplane.

– Where appropriate, storage of BITE reported fault data withina line replaceable unit’s (LRU) nonvolatile memory (NVM) for lateruse.

– Reporting of fault status in the air and on the ground viaoperator displays and/or electronic/magnetic communicationslinks.

– Integration of the fault isolation design to provide completecoverage, from fully automatic BITE through interactive,BITE-assisted fault isolation to manual troubleshootingprocedures.

– Ground-test capability for fault isolation and performance ofLRU replacement tests, functional tests, and system tests.

– OMD in both displayed and selectively printed forms

– Airplane condition monitoring function integrated with theBITElline maintenance function design.

Airframe and equipment designers are encouraged to takeadvantage of this guidance information, beginning with the earliestdesign phases of new equipment.

Users may also find this information helpful in standardizingmaintenance planning and procedures, and in securing appropriaterecognition for such procedures from the regulatory agencies. It isparticularly important that the guidelines set forth herein shouldbe considered in terms of the overall perspective of the users’needs, rather than some more limited objective.

Edition:

91

Published:

03/28/1991

Number of Pages:

70

File Size:

1 file , 3.2 MB