The AD the Due List Missed

No. The 10 % tolerance belongs to the maintenance programme tasks; it does not extend an AD compliance time.

• ADs are mandatory continuing-airworthiness requirements. The aircraft may not be operated unless the AD is complied with within its stated limits. A tolerance in the approved maintenance programme applies to tasks generated by the programme, not to a limit imposed by an AD.
• An extension is possible only where the AD itself provides for it, or where an alternative method/timing has been approved by the authority that issued the AD. Otherwise the limit stands.

How the CAMO should control it:

1. Incorporate the AD into the aircraft's maintenance programme and due-list at the moment of receipt, with a distinct 'AD' task identifier so it can never be merged into a routine check tolerance.
2. Establish per aircraft the datum the AD uses - flight hours accumulated from the effective date, or calendar months - and track it against the actual FH count, not the projected utilisation.
3. Plan the accomplishment with margin: an inspection forecast to fall due during a C-check is scheduled at the C-check only if the due point is genuinely later.
4. Where an AD-specified interval and a programme task coincide, the AD limit governs the earlier of the two.

On these facts, msn 812 is planned for inspection before it reaches 600 FH from the effective date, or before 12 months - whichever comes first - regardless of the C-check date.

The aircraft is in non-compliance and must be grounded until the AD inspection is accomplished.

Sequence:

1. Stop operations - instruct the operator that msn 795 is not to fly; the CAMO cannot authorise flight with an AD outstanding.
2. Establish the facts - how many FH beyond the limit, over what period, on which flights; whether the due point was miscalculated (wrong FH datum, unincorporated AD, planning error) or simply missed.
3. Accomplish the AD at the earliest opportunity and certify it; if the inspection reveals defects, handle them to the approved data before release.
4. Assess airworthiness of the flights already made - was there an unsafe condition during those flights? That assessment drives the urgency and the reporting.
5. Report. An AD exceedance is an airworthiness-relevant event: raise it through the mandatory/occurrence-reporting system and inform the competent authority, the operator, and the owner/lessor if contractually required. Do not wait for the investigation to be complete before notifying.
6. Root cause and corrective action - audit the AD-incorporation process across the whole fleet, verify the other eleven aircraft, correct the due-list logic, retrain, and record the corrective action in the CAMO's quality system.

The exceedance is not closed by doing the inspection; it is closed when the organisation can show why it will not recur.

Not on that basis. The note has to be applied as written and evidenced.

• The AD note exempts the initial inspection for aircraft whose MLG has been overhauled in accordance with the SB, because the overhaul is deemed to embody the required work. Whether rev 2 does embody it depends on what rev 3 added: if rev 3 introduces a pintle-pin check that rev 2 did not include, an overhaul to rev 2 has not accomplished equivalent work.
• The CAMO's options, in order of preference: (a) accomplish the AD inspection as written - the simplest and always defensible route; or (b) obtain written confirmation from the TC holder, or from the authority that issued the AD, that overhaul to rev 2 satisfies the intent, supported by the workshop findings from the overhaul, and record that determination on the compliance file before relying on it.

A CAMO engineer's own opinion that 'rev 2 is close enough' is not a basis for non-compliance. Credit for previous work must be evidence-based, documented, and traceable to the AD's own wording.