Suspect landing gear bolts and a certificate that does not match the order
An A321 is AOG at Hong Kong with a main landing gear attachment bolt rejected at inspection. A broker delivers 24 replacement bolts within four hours. The purchase order and the illustrated parts catalogue both call for part number ABS-1234-03. The accompanying airworthiness release certificate shows ABS-1234-04, and the remarks block states 'interchangeable with -03 subject to service bulletin ABS-1234-32-005'. The aircraft's service bulletin status shows that bulletin has not been embodied and is not in the approved maintenance programme. The certificate is a photocopy, the status block is legible but the issuing organisation's approval number is not printed, the bolts are loose in a single bag with no batch or heat-treatment traceability, and the only marking is a hand-etched number on two of the bolts. The supplier is not on the operator's approved supplier list. The certifying engineer says the bolts 'look identical and are the right grip length'.
1. Accept or reject the batch? Give your reasoning against the acceptance requirements.
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Reject the batch. Acceptance of components is a documentary and physical process, and this consignment fails both.
The certificate does not match the required part. The part number on the release document is -04, while the aircraft requires -03. The claimed interchangeability is conditional on a service bulletin that is not embodied and not in the approved maintenance programme; a remark on a certificate cannot create eligibility. Eligibility is established by the type design and the aircraft's configuration, not by a note in a remarks block.
The document itself is not acceptable. A photocopy cannot be verified, the issuing organisation's approval number is missing so the certificate's provenance cannot be checked, and the status block must be clear and unambiguous. Loose bolts in one bag with no batch, lot or heat-treatment traceability break the chain from the approved production source to the aircraft; without it there is no way to show the bolts are what the certificate says they are.
The physical condition compounds it. Hand-etched part numbers are not acceptable identification for a life-limited, flight-critical fastener, and the absence of manufacturer marking is a strong indicator of an unapproved source. 'Looks identical and is the right grip length' is a visual comparison, not an acceptance. Grip length, thread, material, finish, and load rating matter, and a bolt that looks right in the hand is exactly the kind of part that fails in service.
Accepting this batch would put an unverified component on a principal structural element and falsify the aircraft's configuration record.
2. What do you do with the parts now, and who needs to be told?
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Quarantine, segregate, document, notify.
The batch goes into a clearly marked quarantine area with a hold tag that identifies it as suspected unapproved, not just as awaiting documentation. It must be physically separated so it cannot be picked by mistake on a later shift, and it must not be returned to the broker before the investigation has the evidence it needs.
Records: photograph the certificate, the packaging, the markings, and the delivery note; record the purchase order, the broker's identity, the courier details and the time of receipt; retain the whole consignment intact. Note who brought it into the organisation and who inspected it.
Notifications: the organisation's quality manager and the accountable manager, who will decide on the suspected unapproved parts process; the Civil Aviation Department, since suspected unapproved parts are a reportable safety concern under the occurrence reporting scheme; the operator's continuing airworthiness management organisation, so the aircraft's records and any other use of this supplier are checked; and the type certificate holder if the part number or marking suggests a counterfeit. The broker should be told in writing that the consignment is under investigation, without returning it.
I would also widen the search immediately: check whether this broker has supplied anything else to the organisation or to the operator's other stations in the past twelve months, and check the parts store for other -04 bolts, because the same error may already be on a shelf or, worse, on an aircraft.
3. The aircraft must fly. What lawful routes exist, and how would you choose between them under time pressure?
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The pressure does not change the requirements; it changes which compliant route I pursue first.
Routes, in the order I would evaluate them:
Certified bolt from an approved source. Operator's own store, the OEM or an approved distributor, or another operator under a documented loan with full traceability. This is the fastest route if stock exists in the region, and it preserves the configuration. I would ask the OEM and the type certificate holder's AOG desk first, not the broker.
Same part number from a different, approved supplier with a verifiable release certificate, correct part number, approval number, and batch traceability. The part is only acceptable when the document, the marking and the aircraft configuration all line up.
Embodiment of the service bulletin that would make the -04 bolt eligible, if the design approval covers it and the operator's engineering and continuing airworthiness functions accept the change with the correct records and any inspection implications. This is an engineering decision with a paperwork trail, not an acceptance decision made in the stores.
Alternative part number approved by the design organisation, with an approved eligibility statement.
I would reject any suggestion of fitting the parts 'pending paperwork'. Deferred documentation for a flight-critical fastener becomes permanent documentation, and the aircraft's configuration record is then wrong. I would also tell operations the realistic timescale rather than a hoped-for one, so they can plan around a grounded aircraft instead of a rushed and unlawful release.