Table of Contents
1.0INTRODUCTIONANDDESCRIPTION
1.1PurposeofThisCharacteristic
1.2FunctionsandModesofOperation
1.2.1ModesofVerticalOperation
1.2.2ModesofHeadingOperation
1.3Reliability
1.4UnitDescription
1.4.1AttitudeandHeadingReferenceUnit(AHRU)
1.4.2MagneticSensorUnit(MSU)
1.4.3RemoteMagneticCompensationUnit(RMCU)
1.4.4ControlPanel
1.4.5Displays
1.5Interchangeability
1.5.1General
1.5.2UseinARINC704IRSInstallation
1.6RegulatoryApproval
2.0INTERCHANGEABILITYSTANDARDS
2.1FormFactors,Connectors,andIndexPinCoding
2.1.1AttitudeandHeadingReferenceUnit
2.1.2MagneticSensorUnit(MSU)
2.1.3RemoteMagneticCompensatorUnit(RMCU)
2.1.4ControlPanel
2.2InputandOutputSignalCharacteristics
2.3StandardInterwiring
2.4PowerCircuitry
2.4.1ACPowerInput(Primary)
2.5Weights
2.6ThermalInterfaceandDesign
2.6.1AHRU
2.6.2MSU
2.7EnvironmentalTestCategories
2.8AttitudeandHeadingReferenceUnit(AHRU)
Mounting
2.8.1AHRUOrientation
2.8.2AHRUMountingTolerances
2.8.3MSUMountingTolerances
2.9AirplaneDynamicEnvironment
3.0SYSTEMDESIGNCONSIDERATIONS
3.1General
3.1.1RangeofOperation
3.1.2RelationshiptoRemoteComputers
3.1.3NoLatitudeInput
3.2ModesofSystemOperation
3.2.1StandardOperation
3.2.2Automatic`Basic'ModeSelection
3.2.3ManualBasicModeSelection
3.2.4DGModeSelection
3.2.5SelfTest
3.3Outputs
3.3.1AnalogOutputs
3.3.2DigitalOutputs
3.3.2.1AHRSOutput
3.4IntegrityMonitoringandFailureWarning
3.4.1MonitoringRequirements
3.4.2FailureWarningInputs
3.4.3WarningOutputs
3.4.3.1FailureWarningOutputs
3.4.3.2MonitorIntegrity
3.4.4ModeAlertOutputs
3.5BuiltInTestEquipment(BITE)
3.6Accuracy
3.6.1VerticalDynamicOperatingErrors
3.6.2VerticalStaticOperatingErrors
3.6.3PlatformHeading
3.7AHRSGroundSpeed(CustomerOption)
4.0STANDARDSIGNALCHARACTERISTICS
4.1GeneralAccuracyandOperatingRanges
4.1.1Resolution
4.1.2StandardizedOutputSignals
4.1.2.1DigitalDataStandards
4.1.2.2Standard"AppliedVoltage"
4.1.2.3"StandardGround"Signal
4.2Inputs
4.2.1DADSDiscretes
4.3Outputs
4.3.1DigitalDataOutputs
4.3.1.1PrimaryFlightInstrumentData
4.3.1.2FlightControlComputerData
4.3.1.3GeneralDataOutput
4.3.2DiscreteOutputs
4.3.2.1AttitudeWarning
4.3.2.2HeadingWarning
4.3.2.3BasicModeWarning
5.0ATTITUDEANDHEADINGREFERENCEUNITDESIGN
5.1General
5.2MountingRigidity
5.3VibrationIsolators
5.4AttitudeandHeadingReferenceUnitFunctions
6.0MAGNETICSENSORUNIT(MSU)DESIGN
7.0PROVISIONSFORAUTOMATICTESTEQUIPMENT
7.1General
7.2UnitIdentification
7.2.1PinAllocation
7.2.2UseofATLASLanguage
ATTACHMENTS
0AHRSDataUsage
1NotesApplicabletoStandardInterwiring
2ARINC705AHRSStandardInterwiring
3MiddleInsertPinUsage
4ARINC705AHRUConnectorLayout
5-1AttitudeHeadingReferenceUnit(AHRU)
DimensionsandTolerances
5-2AHRUMountingTrayGeneralLayout
5-3AHRUMountingTrayDimensions
6CompassControlPanelLogic
7MagneticSensorUnit
8EnvironmentalTestCategories
9DigitalControlWordFormat
10AHRSDigitalDataSummary
NotesToAttachment10
11AHRSOutputDataPerformance
12(Sheet1)RemoteMagneticCompensatorUnit
12(Sheet2)RMCUTypicalDesign
12(Sheet3)RMCUTypicalDesign
13TypicalControlPanel
APPENDICES
1BibliographyoftheAEECARINC705AHRS
Project
2Non-StandardApplications Abstract
Describes the basic requirements for an AHRS specifically designed for installation in commercial transport aircraft. The AHRS is an attitude and heading sensor that provides outputs in digital form for guidance and display. The AHRS replaces the traditional vertical and directional gyros.
