Release to service of NDT tasks by part-145 organisations

Aircraft class A

Certifying staff required: The release of the works carried out on aircraft has to be performed by certifying staff holding a part-66 licence

Qualification system: Licencing of personnel has to follow part-66 regulation

General Release procedure: The release is either on the aircraft technical log or issuing an aircraft release to service statement

Release procedure for an NDT inspection:
A part-145 organisation holding an A approval rating on a particular aircraft type and having in its approved scope of work NDT inspections for this aircraft type.
This organization needs to have part-66 certifying staff and NDT personnel qualified in accordance with 145.A.30 (f).
In this case the NDT inspector performs the NDT task and signs the work order. The aircraft is released by appropriately qualified B1, B3 or C certifying staff under the organisation’s A rating.

Please note that the release  may include not only the NDT task but also the associated tasks (removal of panels, blankets, wires, re-installation, etc), or the NDT task may be part of a base maintenance check.


Engines Class B 

Certifying staff required: The release of the works carried out on engines has to be performed by engine’s certifying staff

Qualification system: The certifying staff is qualified following the procedures established by the organisation, part-66 licence is not required.

General Release procedure: The release of works performed under class B is done on an EASA form 1 (there are some exceptions for particular cases)

Release procedure for an NDT inspection:
A part-145 organisation holding a B rating approval on a particular engine type and having in its approved scope of work NDT inspections for this engine type.
This organization needs to have “engine” certifying staff (qualified in accordance with company procedures) and NDT personnel qualified in accordance with 145.A.30 (f).
In this case the NDT inspector performs the NDT task and signs the work order. The engine certifying staff releases the works performed to the engine (including NDT inspection) on an EASA form 1



Components Class C

Certifying staff required: The release of the works carried out on aircraft has to be performed by components certifying staff

Qualification system: certifying staff is qualified following the procedures established by the organisation, no need to have a part-66 licence

General Release procedure: The release of works performed under class C is done on an EASA form 1 (there are some exceptions for particular cases)

Release procedure for an NDT inspection:
A part-145 organisation holding a C rating approval on a particular component and having in its approved scope of work NDT inspections for this component.
This organization needs to have “component” certifying staff (qualified in accordance with company procedures) and NDT personnel qualified in accordance with 145.A.30 (f).
In this case the NDT inspector performs the NDT task and signs the Work Order / Engineering Order. The component certifying staff releases the works performed to the component (including NDT inspection) on an EASA form 1



Specialised services Class D

Certifying staff required: The release of the works carried out on aircraft has to be performed by “specialised services” certifying staff

Qualification system: The certifying staff is qualified following the procedures established by the organisation in compliance with EN4179, part-66 licence is not required.

General Release procedure: The release of works performed under class D rating is done on an EASA Form 1 or on a format defined by the organisation in the MOE in compliance with 145.A.50 and approved by the competent authority.

Release procedure for an NDT inspection:
A part-145 organisation holding an D approval on a particular NDT method. The approved scope of work will be NDT inspections on this method.
This organisation needs to have NDT certifying staff qualified in accordance with 145.A.30 (f).
In this case the NDT certifying staff performs and releases the NDT task on an EASA Form 1 or on a release to service document defined by the organisation in the MOE in compliance with 145.A.50 and approved by the competent authority