DOC AIRBUS | AMM A320FNAVIGATION - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The aircraft navigation systems provide the crew with the data required for flight within the most appropriate safety requirements.
These data can be divided into four groups :
** ON A/C NOT FOR ALL The aircraft navigation systems provide the crew with the data required for flight within the most appropriate safety requirements.
Navigation - Systems OverviewwThese data can be divided into four groups :
- Air Data/Inertial Reference System (ADIRS)
- Landing and taxing aids
- Independent position determining
- Dependent position determining.
2. System Description
A. ADIRS
This part of the navigation system comprises :
This part of the navigation system comprises :
- three Air Data/Inertial Reference Units (ADIRU)
- standby systems.
- the air data function through its Air Data Reference (ADR) portion.
- the attitude, heading and position function through its Inertial Reference (IR) portion.
(1) Air data function
Air data are provided by four independent sources :
Air data are provided by four independent sources :
(a) Three main systems
Each of the three main systems includes static probes, pitot probes and their associated Air Data Modules (ADM), Total Air Temperature (TAT) sensors and Angle of Attack (AOA) sensors.
They provide the ADR portion of the ADIRU with the necessary data for the generation of parameters which are transmitted to the Primary Flight Displays (PFD) and Navigation Displays (ND) and the Angle of Attack (AOA) indicator (optional) and to the various aircraft systems.
Each of the three main systems includes static probes, pitot probes and their associated Air Data Modules (ADM), Total Air Temperature (TAT) sensors and Angle of Attack (AOA) sensors.
They provide the ADR portion of the ADIRU with the necessary data for the generation of parameters which are transmitted to the Primary Flight Displays (PFD) and Navigation Displays (ND) and the Angle of Attack (AOA) indicator (optional) and to the various aircraft systems.
(b) A standby system
1 The standby system includes a standby altimeter, a standby airspeed indicator and a metric altimeter (optional) (Ref. 34-21) and the optional system ISIS (Ref. 34-22). They are provided with pressure by static probes and pitot probe linked to the ADIRU 3.
More explanations are given in the ADIRU system (Ref. 34-13).
More explanations are given in the ADIRU system (Ref. 34-13).
(2) Attitude, heading and position function
Attitude, heading and position data are provided by four independent sources:
Attitude, heading and position data are provided by four independent sources:
(a) Three main systems
The three main systems are made up of the following components :
The primary information of rotation rates and linear acceleration measured by the IR portions are directly used by the Auto Flight System (AFS), by the Flight Augmentation Computer (FAC) and the Flight Management and Guidance Computer (FMGC).
The IR data are transmitted to the indicators (PFD, ND and RMI) and to the various aircraft systems.
The three main systems are made up of the following components :
- three IR portions
- a Control and Display Unit (CDU).
The primary information of rotation rates and linear acceleration measured by the IR portions are directly used by the Auto Flight System (AFS), by the Flight Augmentation Computer (FAC) and the Flight Management and Guidance Computer (FMGC).
The IR data are transmitted to the indicators (PFD, ND and RMI) and to the various aircraft systems.
(b) A standby system
1 The standby system includes a standby horizon indicator and a standby compass (Ref. 34-22).
More explanations are given in the ADIRU system (Ref. 34-14).
More explanations are given in the ADIRU system (Ref. 34-14).
(3) Attitude, heading and position function
Four sources that operate independently supply the attitude, heading and position data.
Four sources that operate independently supply the attitude, heading and position data.
(a) Three primary systems
The three primary systems have the components that follow:
The Auto Flight System (AFS), the Flight Augmentation Computer (FAC) and the Flight Management and Guidance Computer (FMGC) directly use the primary data related to the rotation rates and linear acceleration measured by the IR parts.
The IR data is transmitted to the indicators (PFD, ND and RMI) and to the different aircraft systems.
The three primary systems have the components that follow:
- Three IR portions
- A Mode Selector Unit (MSU).
The Auto Flight System (AFS), the Flight Augmentation Computer (FAC) and the Flight Management and Guidance Computer (FMGC) directly use the primary data related to the rotation rates and linear acceleration measured by the IR parts.
The IR data is transmitted to the indicators (PFD, ND and RMI) and to the different aircraft systems.
(b) A standby system
1 The standby system includes a standby horizon indicator and a standby compass (Ref. 34-22).
More data is given in the ADIRU system chapter (Ref. 34-14).
More data is given in the ADIRU system chapter (Ref. 34-14).
B. Integrated Standby Instrument System (ISIS) (optional system)
The Integrated Standby Instrument System (ISIS) indicator replaces the three conventional standby instruments i.e.:
The Integrated Standby Instrument System (ISIS) indicator replaces the three conventional standby instruments i.e.:
- the standby altimeter (and standby altimeter in meters -optional-)
- the standby airspeed indicator
- the standby horizon indicator.
The standby heading is given by a magnetic compass, which is an independent instrument.
(1) The ISIS indicator, provides the following standby data on a Liquid Crystal Display (LCD) installed in place of the standby horizon:
- Attitude,
- Standard or baro-corrected altitude and related barometric pressure
- Indicated airspeed and Mach number
- Lateral acceleration
and the following optional parameters: - ILS deviation
- V-bar aircraft symbol
- Barometric pressure in hPa or in hPa and in.Hg
- Altitude in meters.
In addition, two specific functions are available: - Display and adjustment of four airspeed bugs and four airspeed altitude bugs
- Automatic test procedure.
More explanations are given in the ISIS system (Ref. 34-22).
C. Landing and Taxiing Aids
This part of the navigation system comprises :
This part of the navigation system comprises :
(1) Paravisual Indicator (PVI) (optional system)
The aircraft is equipped with one PVI installed on the glareshield panel 131VU, Captain's side.
This system provides the Captain with an image which serves as a piloting aid for take-off and landing in reduced visibility conditions.
The system receives parameters from the DMC1 which can be switched to the DMC3, and generates the image.
More explanations are given in the PVI system (Ref. 34-34).
The aircraft is equipped with one PVI installed on the glareshield panel 131VU, Captain's side.
This system provides the Captain with an image which serves as a piloting aid for take-off and landing in reduced visibility conditions.
The system receives parameters from the DMC1 which can be switched to the DMC3, and generates the image.
More explanations are given in the PVI system (Ref. 34-34).
(2) Head Up Display (HUD) (optional system)
The aircraft is equipped with :
The HUDC processes the input parameters received from the Display Management Computer 1 (DMC1), which can be switched to the DMC3, and sends them to the OHU after transformation.
More explanations are given in the HUD system (Ref. 34-35).
The aircraft is equipped with :
- a HUDC (Head Up Display Computer)
- a OHU (Optical Head Unit).
The HUDC processes the input parameters received from the Display Management Computer 1 (DMC1), which can be switched to the DMC3, and sends them to the OHU after transformation.
More explanations are given in the HUD system (Ref. 34-35).
(3) Instrument Landing System (ILS) or Multi-Mode Receiver (MMR) (optional system)
Both ILS or MMR receivers are controlled from FMGCs and Radio Management Panels (RMPs) featuring two output channels, one command output and one dialog output.
All data are shown on the EFIS displays.
More explanations are given in the ILS system (Ref. 34-36).
Both ILS or MMR receivers are controlled from FMGCs and Radio Management Panels (RMPs) featuring two output channels, one command output and one dialog output.
All data are shown on the EFIS displays.
More explanations are given in the ILS system (Ref. 34-36).
(a) The ILS system enables to know the aircraft position during the landing phase with respect to a predetermined descent path.
This system is composed of:
This system is composed of:
- two ILS receivers
- a Localizer antenna
- a Glide/Slope antenna.
(b) The MMR system is a navigation system with two internal receivers, the Instrument Landing System (ILS) and the Global Positioning System (GPS).
1 The ILS function is to provide the crew and the airborne system users with lateral (LOC) and vertical (Glide/Slope) deviations signals, with respect to the approach ILS radio beam transmitted by a ground station.
2 The GPS function is a radio aid to worldwide navigation which provides:
- the crew with a readout of accurate navigation information, e.g. position, track and speed.
- the Flight Management and Guidance Computer (FMGC) with position information, for accurate position fixing.
- two MMR receivers
- a Localizer antenna
- a Glide/Slope antenna
- two GPS ACTIVE antennas.
D. Independent Position Determining
This part of the navigation system, which is basically independent of ground installations, provides data on the position of the aircraft. It comprises :
This part of the navigation system, which is basically independent of ground installations, provides data on the position of the aircraft. It comprises :
(1) Weather Radar (WXR) system
The Weather Radar (WXR )system is a X-band system which can have the Predictive WindShear (PWS) function. This system has the functions that follow:
The Weather Radar (WXR )system is a X-band system which can have the Predictive WindShear (PWS) function. This system has the functions that follow:
- Detection and localization of the atmospheric disturbances in the area by antenna scanning and visual display of their intensity
- Display of terrain mapping information by the combination of the the radar beam orientation and of the receiver gain
- Detection and display of windshear events in the area given by the antenna scanning (if the PWS operates).
NOTE: The Electronic Flight Instrumenta System (EFIS) controls the operation and superimposes the weather picture on the ND.
This system has the components that follow: - One or two transceivers (transceiver 2 is optional)
- A control unit
- A flat plate antenna and its drive unit.
(2) Radio Altimeter (RA)
The function of the Radio Altimeter (RA) is to give accurately and continuously the height of the aircraft from 0 to 2500 ft above the terrain independently of the atmospheric pressure.
The Height and Decision Height data are shown on the PFD. The Multipurpose Control and Display unit (MCDU) lets you select and read the Decision Height.
The RA system has the components that follow:
The function of the Radio Altimeter (RA) is to give accurately and continuously the height of the aircraft from 0 to 2500 ft above the terrain independently of the atmospheric pressure.
The Height and Decision Height data are shown on the PFD. The Multipurpose Control and Display unit (MCDU) lets you select and read the Decision Height.
The RA system has the components that follow:
- Two transceivers
- Four identical antennas, one for transmission and one for reception for each transceiver.
(3) Traffic Alert and Collision Avoidance System (TCAS) (optional system)
The TCAS protects a volume of airspace around the aircraft. The function of the TCAS II is to calculate the range, altitude and bearing of the other aircraft that have Air Traffic Control (ATC) transponders. The system monitors the trajectory of the other aircraft to make sure that there is no collision risk. If there is a risk, the system gives the pilots aural and visual advisories which give the vertical avoidance maneuvers.
The aircraft has these components:
Traffic advisories are shown on the EFIS displays.
More information is given in the TCAS system chapter (Ref. 34-43).
The TCAS protects a volume of airspace around the aircraft. The function of the TCAS II is to calculate the range, altitude and bearing of the other aircraft that have Air Traffic Control (ATC) transponders. The system monitors the trajectory of the other aircraft to make sure that there is no collision risk. If there is a risk, the system gives the pilots aural and visual advisories which give the vertical avoidance maneuvers.
The aircraft has these components:
- A TCAS computer unit
- Two TCAS antennas.
Traffic advisories are shown on the EFIS displays.
More information is given in the TCAS system chapter (Ref. 34-43).
(4) Ground Proximity Warning System (GPWS)
This system tells the crew if the aircraft is in a dangerous configuration when it goes near the ground in a non-predetermined manner.
This system tells the crew if the aircraft is in a dangerous configuration when it goes near the ground in a non-predetermined manner.
(a) The GPWS gives aural and visual warnings if the aircraft is in a possible dangerous condition related to:
- Mode 1 - Excessive rate of descent
- Mode 2 - Excessive closure rate with terrain
- Mode 3 - Descent after takeoff and minimum terrain clearance
- Mode 4 - Unsafe terrain clearance
- Mode 5 - Descent below glide slope.
(b) Enhanced GPWS (optional system)
The function of the Enhanced GPWS is to alert the flight crew of possible dangerous conditions related the terrain.
The Enhanced GPWS has basic Modes 1 to 5 and the other enhanced functions that follow:
The function of the Enhanced GPWS is to alert the flight crew of possible dangerous conditions related the terrain.
The Enhanced GPWS has basic Modes 1 to 5 and the other enhanced functions that follow:
- Terrain Clearance Floor (TCF) function. It creates an increasing terrain clearance envelope around the intended airport runway directly related to the distance from the runway. The TCF function gives aural and visual alerts.
- Terrain Awareness alerting and Display (TAD) function. This function uses the aircraft geographic position, the aircraft altitude and a terrain data base if there are conflicts between the aircraft flight path and the terrain, and to show graphic displays of the conflicting terrain on the NDs.
The terrain awareness alerting-algorithms continuously calculate terrain clearance envelopes in front of the aircraft.
(5) Traffic and Terrain Collision Avoidance System (T2CAS) (optional system)
The T2CAS has two functions:
The T2CAS has two functions:
- Traffic Alert and Collision Avoidance System (TCAS): TCAS II Change 7.
- Terrain Awareness and Warning System (TAWS).
- Collision with terrain (Controlled Flight Into Terrain).
- Collision with surrounding traffic.
- Detects the dangerous conditions
- Alerts the crew of the aircraft environment
- When possible, gives escape maneuvers.
(6) Traffic and Terrain Collision Avoidance System (T3CAS) (optional system)
All information is given in the Traffic and Terrain Integrated Surveillance System (T/TISS) chapter (Ref. 34-72).
All information is given in the Traffic and Terrain Integrated Surveillance System (T/TISS) chapter (Ref. 34-72).
E. Dependent Position Determining
This part of the navigation system comprises :
This part of the navigation system comprises :
(1) Distance Measuring Equipment (DME)
The DME enables the distance separating the aircraft from one or two DME station being received to be known.
The DME is made up of two systems comprising respectively :
The slant range distance is displayed on NDs and PFDs.
More explanations are given in the DME system (Ref. 34-51).
The slant range distance is displayed also on a VOR/DME Radio Magnetic Indicator (RMI) or a VOR/ADF/DME RMI (optional) (Ref. 34-57).
The DME enables the distance separating the aircraft from one or two DME station being received to be known.
The DME is made up of two systems comprising respectively :
- a DME interrogator
- a transmission/reception antenna.
The slant range distance is displayed on NDs and PFDs.
More explanations are given in the DME system (Ref. 34-51).
The slant range distance is displayed also on a VOR/DME Radio Magnetic Indicator (RMI) or a VOR/ADF/DME RMI (optional) (Ref. 34-57).
(2) Air Traffic Control (ATC)
The ATC allows an operator of the corresponding equipment on the ground to locate and identify the aircraft in flight without having to communicate with the crew.
The system is made up of the following components :
The ATC allows an operator of the corresponding equipment on the ground to locate and identify the aircraft in flight without having to communicate with the crew.
The system is made up of the following components :
- two ATC transponders
- a ATC/TCAS control unit
- four ATC antennas: two bottom antennas and two top antennas (optional).
(3) Automatic Direction Finder (ADF)
The ADF enables the bearings of one or two ADF ground transmitter stations to be permanently indicated with respect to the aircraft heading.
The system is made up of the following components :
The ADF bearings are displayed on:
The ADF enables the bearings of one or two ADF ground transmitter stations to be permanently indicated with respect to the aircraft heading.
The system is made up of the following components :
- one or two transceivers (transceiver 2 is optional)
- two ADF loop and sense antennas.
The ADF bearings are displayed on:
- two EFIS Navigation Displays (in Rose mode).
- a Radio Magnetic Indicator (RMI) (optional) (Ref. 34-57).
(4) VHF Omni-Range (VOR)
The VOR firstly enables the bearings of one or two VOR ground transmitter stations to be permanently indicated with respect to the aircraft heading, and secondly it indicates the aircraft course deviation with respect to a preselected course.
The system is made up of the following components :
VOR data are displayed on:
More explanations are given in the VOR/MARKER system (Ref. 34-55).
The VOR firstly enables the bearings of one or two VOR ground transmitter stations to be permanently indicated with respect to the aircraft heading, and secondly it indicates the aircraft course deviation with respect to a preselected course.
The system is made up of the following components :
- two VOR/MKR receivers
- a VOR antenna to supply the two VOR/MKR receivers
- a MARKER antenna to supply the VOR/MKR receiver 1 which is the only one to ensure the MARKER function.
VOR data are displayed on:
- two EFIS PFDs
- two EFIS NDs
- a VOR/DME Radio magnetic Indicator (RMI) or a VOR/ADF/DME RMI (optional) (Ref. 34-57).
More explanations are given in the VOR/MARKER system (Ref. 34-55).
(5) Global Positioning System (GPS) (optional system)
The GPS system is a radio aid to worldwide navigation which provides:
The GPS system is composed of:
The GPS system is a radio aid to worldwide navigation which provides:
- the crew with a readout of accurate navigation information, e.g. position, track and speed.
- the Flight Management and Guidance Computer (FMGC) with position information for accurate position fixing.
The GPS system is composed of:
- two GPS Sensor Units (GPSSUs)
- two GPS antennas.