DOC AIRBUS | AMM A320FLAND CAT III CAPABILITY TEST - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The function of the test is to do a check of the capability of the applicable systems to do a CAT 3 DUAL operational-failure automatic-landing. It also does a check of the takeover and important pushbutton switches, the A/THR pushbutton switches and the warnings related to the automatic landing.
The LAND TEST function is used in the Fault Isolation and Detection System (FIDS) and uses the Flight Guidance (FG) failure detection (snapshot, analysis and reporting).
Thus, the LAND TEST function efficiency is the same as the FG Built-In Test Equipment (BITE) efficiency.
** ON A/C NOT FOR ALL The function of the test is to do a check of the capability of the applicable systems to do a CAT 3 DUAL operational-failure automatic-landing. It also does a check of the takeover and important pushbutton switches, the A/THR pushbutton switches and the warnings related to the automatic landing.
The LAND TEST function is used in the Fault Isolation and Detection System (FIDS) and uses the Flight Guidance (FG) failure detection (snapshot, analysis and reporting).
Thus, the LAND TEST function efficiency is the same as the FG Built-In Test Equipment (BITE) efficiency.
2. System Description
During the test, the operator receives:
During the test, the operator receives:
- Instructions that he/she must obey and visual indications on the "MCDU" pages
- Audio indications.
This is to start a BITE analysis if the operator pushes the "YES" line select key at the first question or the "NO" line select key at one of the others and then to write a report and to show it.
No special tool is necessary to do this test.
The initial conditions are aircraft on ground and power supply on.
A. Test Acceptation
The LAND TEST function selection on the Multipurpose Control & Display Unit (MCDU) causes the transmission of the FIDS request (LAND TEST REQUEST), confirmed by the ground condition (discrete with wires), to the four Flight Management and Guidance Computers (FMGC) BITEs (FG1 COM, MON, FG2 COM and MON).
Each BITE sends the request signal to the operational software which generates the answer (LAND TEST ACCEPTATION). This answer is then sent back to the FIDS to let the LAND TEST function start.
The four acceptations from the four FMGC BITEs are necessary for the FIDS to let the test start. Without acceptation, the "LAND TEST REFUSED" message comes into view on the first "AFS/LAND TEST-1" page.
If the test request is accepted, the FIDS generates the different pages which will come into view on the MCDU and communicates with the four FMGC BITEs to do the test.
The LAND TEST function selection on the Multipurpose Control & Display Unit (MCDU) causes the transmission of the FIDS request (LAND TEST REQUEST), confirmed by the ground condition (discrete with wires), to the four Flight Management and Guidance Computers (FMGC) BITEs (FG1 COM, MON, FG2 COM and MON).
Each BITE sends the request signal to the operational software which generates the answer (LAND TEST ACCEPTATION). This answer is then sent back to the FIDS to let the LAND TEST function start.
The four acceptations from the four FMGC BITEs are necessary for the FIDS to let the test start. Without acceptation, the "LAND TEST REFUSED" message comes into view on the first "AFS/LAND TEST-1" page.
If the test request is accepted, the FIDS generates the different pages which will come into view on the MCDU and communicates with the four FMGC BITEs to do the test.
B. Test Principle
This test is for the check of the correct operation of the systems which are in or out of the Automatic Flight System (AFS) and applicable to the CAT 3 operational failure automatic landing (correct operation of the FMGC BITEs, correct system reception, self-test results, interconnections validity).
This test is for the check of the correct operation of the systems which are in or out of the Automatic Flight System (AFS) and applicable to the CAT 3 operational failure automatic landing (correct operation of the FMGC BITEs, correct system reception, self-test results, interconnections validity).
C. Test
LAND TEST (Accepted) ** ON A/C NOT FOR ALL
LAND TEST (Accepted) ** ON A/C NOT FOR ALL
LAND TEST (Accepted) ** ON A/C NOT FOR ALL
If a failure occurs before the acceptation phase, the test is refused.
If a failure occurs after the acceptation phase, the FMGCs stay in the LAND TEST condition because the aircraft is on ground with the engines stopped.
From the "AFS/LAND TEST-4" page, the operator must answer "YES" or "NO" to questions on the MCDU.
If the answer is YES, the LAND TEST continues until the "AFS/LAND TEST-9" last page is shown with the "XXX LAND TEST OK" message.
If the answer is NO:
LAND TEST (Accepted) ** ON A/C NOT FOR ALL LAND TEST (Accepted) ** ON A/C NOT FOR ALL LAND TEST (Accepted) ** ON A/C NOT FOR ALL If a failure occurs after the acceptation phase, the FMGCs stay in the LAND TEST condition because the aircraft is on ground with the engines stopped.
From the "AFS/LAND TEST-4" page, the operator must answer "YES" or "NO" to questions on the MCDU.
If the answer is YES, the LAND TEST continues until the "AFS/LAND TEST-9" last page is shown with the "XXX LAND TEST OK" message.
If the answer is NO:
- An analysis is made at the level of the AFS BITEs to detect and isolate the failure, and
- A fault message comes into view on the "AFS/LAND TEST REPORT" page. It tells the operators to do a check of the systems related to the analysis.
NOTE: Each "AFS/LAND TEST" page shows the "END OF TEST" indication.
When the operator pushes the line select key adjacent to this indication, the "END OF TEST FIDS" command is transmitted to the four FG BITEs.
The reception of this command causes the loss of the LAND TEST ACCEPTATION condition for each BITE.
The LAND TEST function makes possible the test of the Microwave Landing System (MLS) and the GBAS (Ground Based Augmentation System) Landing System (GLS) (provision) landing systems together with the Instrument Landing System (ILS) system ("AFS/LAND TEST-0" page).
NOTE: The "AFS/LAND TEST-0" page shows all the landing systems that are available.
Also, a "TEST CLOSE-UP" page is added to replace the aircraft systems in their initial conditions.