rationals about MAINT STS on A320
Dear All,
My little contribution:
- for reasons given in the quotes above, a MEL should be opened for any MAINT STS displayed.
- at beginnning of each ATA, in the MEL Item Chapter, you have the reference of the MEL item to open for a MAINT STS
- condition or not for DMC and BLEED MAINT STS: yes, this depends on configuration of your aircraft: MSN, MOD/SB status. Master MEL should give you which condition applies or not.
Regarding the F/CTRL MAINT STS noticed during pre-flight checks, this is a recurring question I've had with various airlines, and if this helps you, I give you my genral recommendation:
- pre flight checks are under reponsibility of the Maintenance
- aircraft preparation is under responsibilities of the crew (FCOM-NOR-SOP)
- pre flight check lists must be developped by each airline
- indeed, with ADIRUs are Off, you will have F/CTL MAINT STS message, because many computers (ELACs,SECs, SFCC) uses inputs from ADIRUs
Yes, I saw airlines not asking for ADIRUs to be turned On for the pre flight/daily check. There is no obligation to turn them On for the pre-flight/daily, unless your airline or AA asks for it.
However, as per the sequence of FCOM actions, when crew prepares the aircraft:
- they will first align ADIRUs
- only after, they will press STS P/B at the ECP to check if any MAINT STS is present
- If any MAINT STS is present, they will certainly (and this is an obligation) call the maintenance for opening the corresponding MEL item and this might generate a delay
As a conclusion:
- yes, there is no obligation to align ADIRU during pre flight/daily check
- but you take risk not to detect a MAINT STS that would be noticed by flight crew after aligning ADIRUs, and generating a delay that would certainly be charged to the maintenance
So, why not being pro-active an ask to modify pre-flight/daily checklists used by Maintenace, asking for ADIRU to be turned On before checking STS page (and turning them Off after check)?
That's the recommendation I make to all airline I worked with, and certainly some delays have been avoided, because trouble shooting started before crew arrival.
I wish you all a happy new year