7.2 Design Organisation (DOA) & Production Organisation (POA) Approvals

7.2 Design Organisation (DOA) & Production Organisation (POA) Approvals

Quick Answer: Under EASA Part-21, aeronautical design and manufacturing are strictly separated into two distinct organizational approval frameworks: Subpart J for Design Organisation Approval (DOA) and Subpart G for Production Organisation Approval (POA). A DOA must operate a Design Assurance System (DAS) with independent system monitoring and holds privileges under 21.A.263 to classify changes and approve minor changes/repairs without direct EASA intervention. For smaller or simpler aircraft, Alternative Procedures to DOA (APDOA) under 21.A.14(b) reduce organizational burden. A POA operates an audited quality system under Subpart G and exercises privileges under 21.A.163 to issue EASA Form 1 for newly manufactured parts and EASA Form 52 (Aircraft Statement of Conformity) for new complete aircraft. Production without a POA is governed by Subpart F under direct National Aviation Authority (NAA) inspection, releasing aircraft via EASA Form 53.

Modern aeronautical manufacturing relies on institutional specialization. One enterprise may engineer the structural blue-prints and aerodynamic calculations, while an entirely separate enterprise machines the titanium forgings or assembles the final airframe. To ensure seamless safety oversight, EASA Part-21 establishes distinct regulatory pillars for design and production: Subpart J establishes the standard for design organisations, while Subpart G establishes the standard for production organisations.

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Design Organisation Approval (DOA — Part-21 Subpart J)

Under 21.A.13, an applicant for a Type Certificate, Supplemental Type Certificate, or major design change must demonstrate design capability. For complex products, this demonstration is achieved by holding a Design Organisation Approval (DOA) issued by EASA under Subpart J.

The Design Assurance System (DAS — Rule 21.A.239)

The foundation of a DOA is its Design Assurance System (DAS). The DAS is an integrated, documented operational system that controls and supervises the design, design changes, and repair schemes of aeronautical products. The DAS must ensure that:

1. Every design activity conforms to the applicable Certification Specifications (CS) and environmental protection rules;
2. All compliance documentation (stress reports, ground vibration tests, flight test data, software verifications) is completely verified and systematically controlled;
3. An Independent System Monitoring function (equivalent to an internal quality audit system) continuously evaluates the adequacy, integrity, and strict adherence of the organisation's procedures.

Key Roles in a Design Organisation

• Head of Design Organisation (HDO): Holds corporate and financial authority over design processes;
• Chief of the Office of Airworthiness (COA): Serves as the primary regulatory liaison with EASA, ensuring compliance verification policies are strictly executed;
• Compliance Verification Engineers (CVEs): Senior technical specialists in disciplines such as structures, avionics, flight mechanics, and propulsion. CVEs hold personal signatory authority to independently evaluate and sign off compliance documents, certifying that specific CS requirements have been met;
• Head of Independent System Monitoring: Operates independently of the design departments to audit processes and report directly to the Chief Executive.

The Design Organisation Exposition (DOE / DHOE — Rule 21.A.243)

The organisation must submit a Design Organisation Exposition (DOE)—frequently termed the Design Organisation Handbook (DHOE)—to EASA. The exposition specifies the management structure, names and qualifications of CVEs, design procedures, testing facilities, and the exact terms and scope of design approval.

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DOA Privileges under Rule 21.A.263

Holding a DOA confers substantial statutory autonomy. Under 21.A.263, an approved DOA is privileged to carry out specific functions without seeking prior permission from EASA for each individual action:

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|                         STATUTORY DOA PRIVILEGES (21.A.263)                       |
+-----------------------------------------------------------------------------------+
| 1. Classification Privileges:                                                     |
|    - Classify changes to type design and repairs as 'Major' or 'Minor'.          |
|                                                                                   |
| 2. Design Approval Privileges:                                                    |
|    - Approve Minor changes to type design AND minor repairs, both under the      |
|      single privilege 21.A.263(c)(2), without EASA review.                        |
|    - Approve MAJOR repair designs only if granted privilege 21.A.263(c)(5).      |
|    - Approve certain MAJOR changes only if granted privilege 21.A.263(c)(8).     |
|                                                                                   |
| 3. Information & Instructions Privileges:                                         |
|    - Issue Service Bulletins, manual revisions, and technical instructions with  |
|      the official statement: "The technical content of this document is approved   |
|      under the authority of DOA ref. [EASA.21J.xxx]".                             |
|                                                                                   |
| 4. Flight Conditions & Permit to Fly Privileges:                                  |
|    - Approve Flight Conditions under 21.A.708 for a Permit to Fly.                |
|    - Issue a Permit to Fly (EASA Form 20b) under approved flight conditions.      |
|                                                                                   |
| 5. Recommendation Privilege:                                                      |
|    - Submit formal compliance declarations recommending that EASA issue a TC/STC.|
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The Boundary of Autonomy: A DOA cannot unilaterally approve initial Type Certificates, cannot approve major changes unless granted the extended privilege at 21.A.263(c)(8) (21.A.97(a)(2) refers to points (1) and (8) of 21.A.263(c)), cannot approve major repair designs unless granted 21.A.263(c)(5), and cannot issue Airworthiness Directives. These powers remain reserved to EASA.

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Alternative Procedures to DOA (APDOA — Rule 21.A.14(b))

For smaller, less complex aeronautical designs, establishing a full Subpart J Design Assurance System with independent CVEs and extensive exposition manuals would impose prohibitive overhead. To preserve European manufacturing competitiveness, 21.A.14(b) establishes Alternative Procedures to DOA (APDOA).

• Applicability: Used primarily for sailplanes, powered sailplanes, very light aeroplanes (CS-VLA), light sport aeroplanes (CS-LSA), and simple piston engine/propeller installations;
• Structure: The applicant submits a simplified design procedures manual demonstrating technical competence, testing capability, and airworthiness tracking;
• Regulatory Interface: Unlike a full DOA, an organisation operating under APDOA does not possess extensive autonomous classification and approval privileges. EASA maintains closer direct oversight, reviewing compliance documents and approving changes directly.

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Production Organisation Approval (POA — Part-21 Subpart G)

While a DOA creates the intellectual design, a Production Organisation Approval (POA) issued under Subpart G certifies the physical enterprise manufacturing the hardware. The sole purpose of a POA is to ensure that every manufactured aircraft, engine, propeller, or part strictly conforms to the approved design data and is in condition for safe operation.

The POA Quality System (Rule 21.A.139)

A POA must maintain a comprehensive quality system that provides documented control over every manufacturing stage:

1. Supplier Control: Verifying the pedigree, traceability, and material certifications of raw stock and outsourced parts;
2. Tooling & Calibration: Controlling manufacturing jigs, CNC machinery, torque equipment, and non-destructive testing (NDT) apparatus with traceability to national metrology standards;
3. Non-Conformance Management: Quarantining and segregating defective parts to prevent unapproved parts from entering the supply chain;
4. Independent Quality Audits: Regular internal audits reporting directly to the Accountable Manager.

Production Organisation Exposition (POE — Rule 21.A.143)

The Production Organisation Exposition (POE) is the legal baseline of the POA. It outlines the Accountable Manager's financial commitment, nominated postholders (Head of Quality, Head of Production), facility floor plans, manufacturing processes, inspection criteria, and certifying personnel authorizations.

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POA Privileges and Release Documentation (Rule 21.A.163)

Under 21.A.163, an approved POA exercises specific release privileges using standardized EASA airworthiness forms:

1. EASA Form 1 (Authorized Release Certificate) for New Parts

When a POA manufactures a component, appliance, or engine, it issues an EASA Form 1. In Block 13, the POA selects the "conformity/new part" certification checkbox:

"Certifies that the items identified above were manufactured in conformity to the approved design data and are in a condition for safe operation."

• Vital Exam Distinction: An EASA Form 1 issued by a Part-21 POA certifies that a newly manufactured component conforms to approved design data. An EASA Form 1 issued by a Part-145 maintenance organisation certifies that a used component has been inspected, maintained, repaired, or overhauled in accordance with continuing airworthiness data.

2. EASA Form 52 (Aircraft Statement of Conformity)

When a POA completes the manufacturing of a complete aircraft, it cannot issue a Certificate of Airworthiness—the CofA is a sovereign document issued by the State of Registry. Instead, the POA issues EASA Form 52 (Aircraft Statement of Conformity) under 21.A.163(b).

• The Form 52 certifies that the specific serial-numbered aircraft conforms fully to the Type Certificate (TCDS), that all production flight tests and engine runs were completed satisfactorily, and that the aircraft is in condition for safe operation;
• The owner or operator presents the EASA Form 52 to the National Aviation Authority (NAA) of the State of Registry to obtain the initial Certificate of Airworthiness (EASA Form 25).

3. Maintenance Privileges and EASA Form 53

A POA is privileged under 21.A.163(d) to maintain new aircraft it has manufactured and issue a Certificate of Release to Service (EASA Form 53) for work performed prior to initial delivery to a customer.

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Production Without POA Approval: Part-21 Subpart F

For small-scale manufacturing where holding a full POA is economically unviable (e.g. specialized light aircraft manufacturers producing two or three airframes per year), Subpart F permits Production without POA under strict conditions:

• Authority Agreement (21.A.121): The manufacturer must secure an explicit letter of agreement from the Competent Authority (the national NAA);
• Direct Authority Inspection: The manufacturer holds no autonomous release privileges. Every completed part or complete aircraft must be physically inspected, verified, and certified directly by an NAA airworthiness inspector;
• Release Documents under Subpart F: Under 21.A.130 the manufacturer issues a statement of conformity — an EASA Form 52 for complete aircraft and an EASA Form 1 for other products, parts and appliances — which is only valid when validated by the competent authority. EASA Form 53 is the Part-21 certificate of release to service used for maintenance work, not the Subpart F aircraft conformity document.

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Comparative Matrix: Subpart J (DOA) vs Subpart G (POA) vs Subpart F

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Practical Maintenance Scenario: Receiving Inspection of New vs Maintained Parts

Operational Context

A Part-145 maintenance facility receives two brand-new main landing gear actuator cylinders from a warehouse. The receiving inspector must verify the airworthiness documentation before releasing the cylinders to the hangar floor.

Regulatory Assessment:

1. Component A: Accompanied by an EASA Form 1. In Block 12, the approval reference is FR.21G.0123, and Block 13a carries the signed Part-21 statement of conformity to approved design data (Block 14a left blank). The inspector recognizes this as a newly manufactured part issued by an approved Part-21 Subpart G Production Organisation.
2. Component B: Accompanied by an EASA Form 1. In Block 12, the approval reference is DE.145.0456, the status entered in Block 11 is "Overhauled", and Block 14a carries the signed Part-145 maintenance release statement. The inspector recognizes this as an in-service component released by an approved Part-145 maintenance organisation.
3. Outcome: Both parts are authentic and serviceable, but they originate from completely different regulatory annexes (Part-21 vs Part-145). The receiving inspector logs Component A as new factory stock and Component B as overhauled stock.

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EASA Module 10 Examination Tips & Regulatory Traps

• DAS vs Quality System: A Design Organisation (DOA) operates a Design Assurance System (DAS); a Production Organisation (POA) operates a Quality System.
• CVE Function: Remember the exact role of a Compliance Verification Engineer (CVE): to verify and declare compliance with specific Certification Specifications (CS) within a DOA.
• Form 1 vs Form 52: Form 1 releases components, engines, and parts; Form 52 releases new complete aircraft (Statement of Conformity). DO NOT confuse Form 52 with Form 25 (the Certificate of Airworthiness issued by the NAA).
• Subpart F Oversight: Production without POA (Subpart F, 21.A.121 to 21.A.130) requires the statement of conformity under 21.A.130 to be validated by the Competent Authority. The form is Form 52 for aircraft and Form 1 for other products, parts and appliances.
• DOA Approval Limits: 21.A.263(c)(2) covers minor changes and minor repairs together. Do not attribute minor repairs to (c)(5) — that point is the major repair privilege, and (c)(8) is the extended major change privilege. A DOA can never issue an initial Type Certificate or an Airworthiness Directive.