Who Can Perform an Independent Inspection in Aircraft Maintenance?

An independent inspection is an error-capturing method applied to a critical maintenance task. It is intended to identify errors that could endanger the safe operation of an aircraft before the task is released or signed off.

Under the UK and EASA Part-145 frameworks, an independent inspection must be performed by an appropriately qualified and authorised person who has not carried out or supervised the maintenance task being inspected. The precise requirements are defined by the approved maintenance organisation’s procedures, normally within its Maintenance Organisation Exposition (MOE).

The two people involved

An independent inspection normally involves two distinct roles:

• The authorised person, who performs or supervises the maintenance task.
• The independent qualified person, who independently inspects the completed task.

These roles must not be confused.

The authorised person

The authorised person performs the task, or supervises its performance, in accordance with the applicable maintenance data. This person remains responsible for completing the maintenance task.

Once the independent inspection has been completed satisfactorily, the authorised person issues the certificate of release to service (CRS), or signs off completion of the task in accordance with the organisation’s procedures.

The authorised person does not become the independent inspector simply because they hold a Part-66 licence or a company authorisation. The inspection must be performed by a suitably qualified person who is independent of the original work.

The independent qualified person

The independent qualified person performs the inspection and confirms that:

• the task has been completed satisfactorily; and
• no deficiencies have been identified during the inspection.

This person must be independent of the task. In practical terms, they must not have performed the work or supervised the person who performed it. Independence is therefore both a technical and procedural requirement, not merely a job title.

The organisation’s work card or electronic maintenance system should record the identities of both people and the details of the independent inspection before the CRS or task sign-off is issued.

What qualifications must the independent inspector hold?

There is no single universal licence category called an “independent inspection licence”. Under UK Part-145 and EASA Part-145, eligibility depends on the person’s competence, authorisation and the specific task being inspected.

The independent qualified person will generally be one of the following:

• Certifying staff holding an appropriate Part-66 licence and organisational authorisation.
• Support staff holding the relevant technical authorisation for the aircraft or task.
• Sign-off staff authorised by the organisation to release or sign off the applicable maintenance work.
• A person holding an equivalent authorisation that permits them to release or sign off the critical maintenance task.

A person may also qualify where they are authorised to release or sign off a similar task on a product in a similar category, provided they have received specific practical training for the task being inspected.

A Part-66 licence is important evidence of technical competence, but it does not, by itself, grant permission to perform every independent inspection. The organisation must assess the person’s competence and issue the relevant authorisation under its approved procedures. The EASA continuing airworthiness rules provide the regulatory framework for organisations operating under EASA requirements.

UK CAA and EASA Part-66 considerations

In the UK, aircraft maintenance organisations approved under UK Part-145 must establish procedures for selecting and authorising independent qualified persons. These procedures must comply with the applicable UK regulations and be described in the organisation’s MOE. The UK CAA Part-145 guidance is a useful starting point for understanding the approval framework.

Within the EASA system, the equivalent process applies to EASA Part-145 approved organisations. An EASA Part-66 licence, together with the correct type ratings, experience and organisational authorisation, may support eligibility. The organisation remains responsible for confirming that the individual is competent to perform the particular inspection.

A licence should therefore not be treated as an automatic authorisation. The relevant questions are:

• Does the person have the necessary technical knowledge?
• Do they hold an appropriate licence, approval or equivalent authority?
• Have they completed the required task-specific training?
• Are they current and competent on the relevant aircraft or product category?
• Are they independent of the original task?
• Has the organisation formally authorised them under its MOE?

For additional context, read our guide to UK CAA legislation and Part-145 requirements.

The role of the Maintenance Organisation Exposition

Every UK or EASA Part-145 organisation must maintain an MOE describing how it complies with the applicable requirements. This includes procedures for critical maintenance tasks, error-capturing methods and independent inspections.

The MOE should define:

• what the organisation considers to be a critical maintenance task;
• which tasks require an independent inspection;
• who may perform the inspection;
• what qualifications, training and experience are required;
• how independence is assured;
• how the inspection is recorded; and
• who may issue the final CRS or task sign-off.

The organisation’s definition of an independent inspection should be clearly stated in the MOE. Approved procedures may be more restrictive than the minimum regulatory criteria.

The operator or customer may also define its own list of critical maintenance tasks. In that case, the effective inspection requirement includes both:

• the independent inspections required by the Part-145 organisation’s MOE; and
• any additional inspections required by the operator or customer.

A person may therefore be qualified to perform an inspection for one organisation or contract but not automatically for another. The authorisation must match the approved procedures and scope of the organisation conducting the maintenance.

Competence, experience and records

Experience is an important factor in determining whether someone can perform an independent inspection. A licence or previous authorisation does not remove the need for a task-specific competence assessment.

In the UK, maintenance experience may be documented using records such as a CAP 741 aircraft maintenance engineer’s logbook. These records can help demonstrate practical experience, aircraft exposure and completion of relevant tasks. They do not, by themselves, constitute an independent inspection authorisation. The organisation must still assess the individual against its procedures and issue the appropriate approval.

Our guides to completing a CAP 741 logbook and avoiding common CAP 741 mistakes explain how accurate records can support a licensing application.

For personnel with military maintenance backgrounds, UK Ministry of Defence experience may be considered through the applicable UK CAA recognition and licensing pathways. Military service can provide valuable evidence of aircraft maintenance competence, but the organisation must establish that the individual’s training and experience are relevant to the civil aircraft, component, task and regulatory environment concerned.

Can a pilot perform an independent inspection?

A pilot may be authorised to carry out certain maintenance tasks in limited circumstances, particularly at an unsupported location. Part-145 provisions and associated acceptable means of compliance identify tasks for which a suitably qualified aircraft commander may receive authorisation.

However, a pilot’s authority to carry out a permitted maintenance task does not automatically qualify that pilot to perform an independent inspection of the same task.

Other checks or component replacements involving simple techniques, but not covered by the relevant Part-145 provisions, require the specific agreement of the competent authority. The organisation must also comply with its approved procedures and any applicable operator requirements.

Where a pilot performs a maintenance task, the organisation must still determine who is competent and authorised to inspect it independently. The person conducting the inspection must meet the organisation’s qualification and independence criteria.

What happens when only one person is available?

Independent inspection is normally the primary error-capturing method for a critical maintenance task. A reinspection process may be used as a backup in an unforeseen situation where only one suitably qualified person is available, but only where permitted by the organisation’s approved procedures.

This does not allow an organisation to routinely avoid an independent inspection by assigning the task to one person. The MOE must define the circumstances, controls and recording requirements for any alternative method.

The preferred arrangement remains a genuine independent inspection by a second appropriately qualified and authorised person.

For practical examples of how maintenance teams manage time-critical defects, see our guide to critical tasks and independent inspections.

Are FAA A&P mechanics automatically acceptable in the UK or Europe?

No. A US FAA Airframe and Powerplant (A&P) certificate is a US-specific credential. It does not automatically provide UK Part-145 or EASA Part-145 certifying or independent inspection privileges. The FAA’s official mechanic certification information explains the scope of the US credential.

An FAA-certified mechanic may be accepted by a particular organisation only where the applicable regulatory framework, bilateral arrangements, competent authority approvals and organisational procedures permit it. The organisation must establish the person’s competence and issue any necessary authorisation.

The same principle applies to other national licences and military qualifications. They may support an assessment, but they do not automatically replace the UK CAA or EASA approval and authorisation process. Read our comparison of an EASA licensed engineer and FAA A&P mechanic for broader career context.

The essential requirement

The person performing an independent inspection must be:

• technically competent for the task;
• appropriately licensed, qualified or otherwise authorised;
• trained and current on the relevant aircraft or product;
• independent of the person who performed or supervised the work; and
• formally accepted by the approved maintenance organisation under its MOE.

The authorised person remains responsible for performing or supervising the maintenance task and for issuing the CRS or final task sign-off after the inspection is satisfactory. The independent qualified person provides separate confirmation that the critical task has been completed correctly and that no deficiencies have been found.

That separation of responsibility is the central safeguard. A person is not eligible merely because they hold a maintenance licence. They must also be competent, authorised for the relevant task and genuinely independent of the work being inspected.

Need to demonstrate your maintenance experience clearly? Analyse Your Logbook Today!

Our Part 66 Logbook Analysis tool helps aviation professionals review their records against Part 66 experience requirements and identify areas that may need attention before an application or competence assessment.