Alternate law Airbus 320
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Alternate law Airbus 320
Is it possible to perform auto land in alternate law , when you have all three SEC’s inop. In order to avoid disconnection of autopilot and reverting to direct law ?
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From the MEL ENTRIES a paragraph at the end of each SEC failure (i.e. Sec 1, 2,or 3) basically says if the other two fail Autoland is not permitted.
Maximum landing capability is CAT1
ref MEL 27-94-01A, 02A and 03A
Maximum landing capability is CAT1
ref MEL 27-94-01A, 02A and 03A
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The A320 is definitely capable of auto landing with all SECs inop. Here I am talking systemwise. However, regulation wise it is not permitted...
regarding the "CAT 1 only" indication on FMA, this doesn't always mean that the plane is unable for auto land....it means that AFS is no longer fail passive/operative...
Thanks
regarding the "CAT 1 only" indication on FMA, this doesn't always mean that the plane is unable for auto land....it means that AFS is no longer fail passive/operative...
Thanks
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With all SECs failure, the LGCIUs can still supply ELACs with gear info...
The scenario you are talking about occurs when both LGCIUs fail. In this case the AFS uses SFCCs to switch to Direct Law ..
The fcom I looked at for this failure shows Cat 3 dual inop on the status page which means that Cat 3 single would still be available.
Last edited by tubby linton; 8th Jul 2022 at 19:44.
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No! LGCIUsv don't supply the ELACs in this case. It's flap2 that signals direct law. It's clearly given in FCOM ABN procedures.
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Handsome Goafer 
Right at the bottom of the Operational Procedure for each SEC is the magical line Cat 1 only. Hidden where most normal humans don't go in flight (unless they are REALLY bored).
Strange it's not listed in the required equipment in the Ops section of the QRH given it is a definite requirement and the prohibition is really buried.
Right at the bottom of the Operational Procedure for each SEC is the magical line Cat 1 only. Hidden where most normal humans don't go in flight (unless they are REALLY bored).
Strange it's not listed in the required equipment in the Ops section of the QRH given it is a definite requirement and the prohibition is really buried.
