How to Know If Your Aircraft Is Airworthy Today (Part-ML Checklist)

Under Part-ML, the owner is responsible for continuing airworthiness (ML.A.201), and the aircraft is airworthy only when it conforms to the approved or declared AMP, all applicable ADs, and the type design, with no blocking defects or overdue items. This checklist helps owner-pilots and operators verify that condition before flight: it separates blocking items (do not fly until resolved) from non-blocking items (must be managed but may not alone preclude flight), and provides a practical audit aid. A recent CRS alone is not enough — you must confirm that all AMP tasks, ADs, and component limits are current.

1. Regulatory Context

Under ML.A.201, the owner is responsible for the continuing airworthiness of the aircraft. The aircraft is airworthy when it is in a condition for safe operation and conforms to the approved/declared Aircraft Maintenance Programme (AMP), all applicable Airworthiness Directives (ADs), and the type design. This is both a legal condition (compliance with Part-ML and the AMP) and an operational one (no known defects or overdue items that affect safe operation).

AD vs SB: An Airworthiness Directive (AD) is mandatory; compliance is required within the specified time. A Service Bulletin (SB) is issued by the design or product holder; it is mandatory for airworthiness only if the AMP, the type certificate, or an AD incorporates it. See AD vs SB – What Every Owner Must Understand and Can You Legally Fly with an Overdue AD Under Part-ML?. EASA’s continuing airworthiness framework and Part-ML regulation are the authoritative sources.

2. Practical Interpretation

Blocking vs non-blocking items

Blocking (do not fly until resolved):

• Any overdue mandatory AD (compliance date passed and not deferred in accordance with the AD and regulations).
• Any overdue AMP task that is required for release to service (e.g. annual inspection, recurring inspections per AMP).
• Open defects that the AMP or MEL (if applicable) states must be rectified before flight.
• Exceeded component limits (life-limited parts, overhaul times) that the AMP or type design requires to be current for flight.

Non-blocking (must be managed but may not alone preclude flight):

• Overdue recommended (non-mandatory) ADs or AMP tasks, where the regulation and AMP allow operation with a defined limitation or procedure.
• SBs that are not incorporated by AD or AMP as mandatory (track and plan compliance; do not assume they are optional without checking AMP/AD).
• Deferred items in accordance with the AD or AMP (e.g. within a permitted deferral period or ferry conditions). See Overdue AD.

“False sense of compliance” arises when owners assume that a recent CRS or a clean-looking logbook means the aircraft is airworthy, while an AD is overdue or an AMP task is missed. CRS certifies the work done at that event; it does not certify that all AMP and AD requirements are current. See What Does a CRS Really Mean?.

3. Common Owner Mistakes

• Relying only on the last CRS. The aircraft may have overdue ADs or inspections that are not covered by that CRS.
• Treating SBs as optional without checking. The AMP or an AD may make specific SBs mandatory; ignoring them can be a finding and a safety risk.
• Not tracking component limits. Life-limited parts and overhaul times must be tracked; exceeding them invalidates airworthiness until rectified.
• Flying with “minor” open defects. If the AMP or MEL requires rectification before flight, the defect is blocking regardless of perceived severity.

4. Risk Analysis

What could go wrong? Flying with an overdue AD or overdue mandatory AMP task, or with exceeded component limits, means the aircraft is not in a condition for safe operation in compliance with the law. This can lead to enforcement, insurance issues, and accident liability.

Who is liable? The owner (ML.A.201). The pilot-in-command also has operational responsibility for the flight. Certifying staff are not responsible for the owner’s AMP and AD compliance.

How do findings occur? Audits and ramp checks verify AD status, AMP task status, and component times. Missing or inconsistent records are common findings. See 12 Most Common Part-ML Audit Findings.

5. Practical Audit Checklist

Use this as a daily/pre-flight and periodic audit aid. Each “No” in the blocking section must be resolved before flight.

Blocking items (must be “Yes” or flight is not permitted):

• All mandatory ADs applicable to the aircraft are complied with within the required compliance time (or properly deferred per AD/regulation).
• All AMP tasks that are required for release to service (e.g. annual, recurring inspections) are current (not overdue).
• There are no open defects that the AMP or MEL requires to be rectified before flight.
• Life-limited parts and overhaul times are within limits and recorded.

Non-blocking but required for compliance:

• Recommended ADs / AMP tasks are tracked; any deferral or limitation is documented and within permitted limits.
• SBs that are mandatory per AMP or AD are complied with or scheduled.
• Tech log and maintenance records are up to date (all maintenance and pilot-owner tasks recorded).
• AMP is the current declared/approved version and is actually being followed.

6. FAQ

Can I fly with an overdue inspection?

Only if the AMP or national rules explicitly allow it (e.g. within a short grace period or under a formal deferral). In general, an overdue mandatory inspection means the aircraft is not released to service until that inspection is completed and released (CRS or pilot-owner as applicable). Flying without that is non-compliant and unsafe.

What is the difference between AD and SB?

An AD is issued by the competent authority and is mandatory; you must comply within the stated compliance time unless the AD permits deferral. A SB is issued by the design/product holder; it becomes mandatory for airworthiness only when required by the AMP, type design, or an AD. Always check AD applicability and AMP incorporation of SBs.

Summary: Airworthiness under Part-ML requires AMP current, all applicable ADs complied with, no blocking defects, and component limits within limits. Use the blocking checklist before every flight; keep AD and AMP status, CRS, and tech log in order so you can demonstrate compliance at audit.