Flight Instruments Flashcards
The Air Data Inertial Reference System (ADIRS) provides the Airspeed, Altitude, Attitude, and Aircraft Position to the displays, flight management system, flight controls, engine controls, and other systems.
Basically, the ADIRS replaces the Air Data Computer and IRS that are installed on earlier aircraft types.
The Air Data Inertial Reference System (ADIRS) provides the Airspeed, Altitude, Attitude, and Aircraft Position to the displays, flight management system, flight controls, engine controls, and other systems.
Basically, the ADIRS replaces the Air Data Computer and IRS that are installed on earlier aircraft types.
The major components of the ADIRS include the Air Data Modules(ADMs), the Air Data Inertial Reference Unit (ADIRU), and the Secondary Attitude Air Data Reference Unit (SAARU) .
The ADIRU normally provides Attitude, Air Data, Heading, and Position information.
The SAARU provides an automatic backup for Attitude, Air Data, and limited heading in the event of ADIRU failure.
The major components of the ADIRS include the Air Data Modules(ADMs), the Air Data Inertial Reference Unit (ADIRU), and the Secondary Attitude Air Data Reference Unit (SAARU) .
The ADIRU normally provides Attitude, Air Data, Heading, and Position information.
The SAARU provides an automatic backup for Attitude, Air Data, and limited heading in the event of ADIRU failure.
One pitot probe (left) is mounted on the left forward section of the airplane.
An air data module is connected to each pitot probe.
These air data modules convert dynamic air pressure to a digital output for use by other systems.
The center pitot probe also provides dynamic pressure to the Pitot Standby Air Data Module.
One pitot probe (left) is mounted on the left forward section of the airplane.
An air data module is connected to each pitot probe.
These air data modules convert dynamic air pressure to a digital output for use by other systems.
The center pitot probe also provides dynamic pressure to the Pitot Standby Air Data Module.
All six static ports,( Left, Center, and Right on each side) input to the ADMs.
The Center Static ports also input to the Static Standby ADM (SADM).
All six static ports,( Left, Center, and Right on each side) input to the ADMs.
The Center Static ports also input to the Static Standby ADM (SADM).
The ADMs provide Pitot (airspeed) and Static (air pressure) data to the Left, Center, and Right ARINC 629 Buses(Flight Controls Buses).
In this manner, both the ADIRU and SAARU receive data from all ADMs through 3 independent buses.
The ADIRU and SAARU each validate the air data before it may be used for navigation.
The ADMs provide Pitot (airspeed) and Static (air pressure) data to the Left, Center, and Right ARINC 629 Buses(Flight Controls Buses).
In this manner, both the ADIRU and SAARU receive data from all ADMs through 3 independent buses.
The ADIRU and SAARU each validate the air data before it may be used for navigation.
Angle-of-Attack
There are two angle-of-attack vanes, one located on each side of the forward fuselage.
The vanes measure airplane angle-of-attack relative to the air mass.
Total Air Temperature
A total air temperature probe is mounted outside the airplane to sense air mass temperature.
The temperature sensed by the probe is used by the ADIRU and the SAARU to compute total air temperature.
Static Air Temperature
Static air temperature, displayed on the CDU PROGRESS page, comes from the ADIRU, using total air temperature probe information.
In the event the ADIRU value is invalid, the SAARU computed value is displayed.
Angle-of-Attack
There are two angle-of-attack vanes, one located on each side of the forward fuselage.
The vanes measure airplane angle-of-attack relative to the air mass.
Total Air Temperature
A total air temperature probe is mounted outside the airplane to sense air mass temperature.
The temperature sensed by the probe is used by the ADIRU and the SAARU to compute total air temperature.
Static Air Temperature
Static air temperature, displayed on the CDU PROGRESS page, comes from the ADIRU, using total air temperature probe information.
In the event the ADIRU value is invalid, the SAARU computed value is displayed.
The display system automatically reconfigures to compensate for most faults.
The instrument display source select panels provide manual switches for the pilots to use if certain faults are not corrected automatically.
The Instrument source select switches provide alternate information sources for the PFDs and the NDs. These switches provide automatic source selection when in the off position (switch out, with the ALTN and CDU switch annunciations not visible).
The display system automatically reconfigures to compensate for most faults.
The instrument display source select panels provide manual switches for the pilots to use if certain faults are not corrected automatically.
The Instrument source select switches provide alternate information sources for the PFDs and the NDs. These switches provide automatic source selection when in the off position (switch out, with the ALTN and CDU switch annunciations not visible).
Undetected display source failures, such as missing / faulty display information or intermittent display blanking, may not result in automatic switching.
If there is an undetected source failure, the non-normal (ALTN or CDU) position provides the capability for manual selection of PFD and ND sources.
Undetected display source failures, such as missing / faulty display information or intermittent display blanking, may not result in automatic switching.
If there is an undetected source failure, the non-normal (ALTN or CDU) position provides the capability for manual selection of PFD and ND sources.
AFDS Modes: · LNAV · VNAV · TO/GA · LOC · GS · FPA · TRK HOLD / SEL · HDG HOLD / SEL* Navigation Functions: · FMC VNAV pages · FMC Performance Predictions · ND Wind Direction and Speed (wind arrow) PFD Functions: · Flap Maneuver Speeds · PFD Heading*
Note: * This function is operative when airplane heading is entered on the POS INIT page.
Note: If the airplane is in the polar region when the ARIDU fails, SAARU backup heading for three minutes is not provided.
Note: ND map mode display following ADIRU failure still references TRK.
Note: Autobrakes are also inoperative.
AFDS Modes: · LNAV · VNAV · TO/GA · LOC · GS · FPA · TRK HOLD / SEL · HDG HOLD / SEL* Navigation Functions: · FMC VNAV pages · FMC Performance Predictions · ND Wind Direction and Speed (wind arrow) PFD Functions: · Flap Maneuver Speeds · PFD Heading*
Note: * This function is operative when airplane heading is entered on the POS INIT page.
Note: If the airplane is in the polar region when the ARIDU fails, SAARU backup heading for three minutes is not provided.
Note: ND map mode display following ADIRU failure still references TRK.
Note: Autobrakes are also inoperative.
If ADIRU inertial data fails, the EICAS caution message NAV ADIRU INERTIAL displays. Backup attitude and heading data is available from the SAARU and the following items will be inoperative: or unavailable: all FMC VNAV pages, FMC performance calculations, Flap Maneuvering speeds, Autobrakes and the ND wind speed and direction display. Due to the SAARUs lack of navigation capability, several AFDS modes will also be inoperative. These include: LNAV, VNAV, TO/GA, LOC, GS, FPA, TRK SEL and TRK HLD.
If ADIRU inertial data fails, the EICAS caution message NAV ADIRU INERTIAL displays. Backup attitude and heading data is available from the SAARU and the following items will be inoperative: or unavailable: all FMC VNAV pages, FMC performance calculations, Flap Maneuvering speeds, Autobrakes and the ND wind speed and direction display. Due to the SAARUs lack of navigation capability, several AFDS modes will also be inoperative. These include: LNAV, VNAV, TO/GA, LOC, GS, FPA, TRK SEL and TRK HLD.
With the additional loss of all GPS data, several other functions will be lost.
These include: ND MAP mode, CDU active leg course and distance, CDU direct to waypoint capability, Nav radio autotuning and the ALTN page DIVERT NOW functions.
With the additional loss of all GPS data, several other functions will be lost.
These include: ND MAP mode, CDU active leg course and distance, CDU direct to waypoint capability, Nav radio autotuning and the ALTN page DIVERT NOW functions.
The Secondary Attitude and Air Data Reference Unit (SAARU) is the secondary source for speed, altitude, and attitude information. The SAARU does not provide navigational position data. The SAARU processes information measured by its internal gyros and accelerometers, and from air data module inputs, angle-of-attack vanes, and other systems.
The Secondary Attitude and Air Data Reference Unit (SAARU) is the secondary source for speed, altitude, and attitude information. The SAARU does not provide navigational position data. The SAARU processes information measured by its internal gyros and accelerometers, and from air data module inputs, angle-of-attack vanes, and other systems.
SAARU power-up is completely automatic at airplane power-up.
There are no SAARU controls.
If the ADIRU fails, the SAARU automatically supplies attitude, heading, and air data.
SAARU heading must be manually indexed to the magnetic heading periodically.
SAARU power-up is completely automatic at airplane power-up.
There are no SAARU controls.
If the ADIRU fails, the SAARU automatically supplies attitude, heading, and air data.
SAARU heading must be manually indexed to the magnetic heading periodically.
Upon ADIRU failure, the SAARU supplies attitude data to the PFD and (except for Polar regions) three minutes of backup heading.
The heading is based on ADIRU heading prior to failure.
The CDU POS INIT page shows the SET HDG prompt three minutes after ADIRU failure.
Use the SET HDG prompt to set the SAARU heading to the magnetic heading.
Upon ADIRU failure, the SAARU supplies attitude data to the PFD and (except for Polar regions) three minutes of backup heading.
The heading is based on ADIRU heading prior to failure.
The CDU POS INIT page shows the SET HDG prompt three minutes after ADIRU failure.
Use the SET HDG prompt to set the SAARU heading to the magnetic heading.
When the SAARU is providing air data and attitude indications, the Flap Maneuvering speeds will not display on the PFD.
When the SAARU is providing air data and attitude indications, the Flap Maneuvering speeds will not display on the PFD.
