Chap 2: Airworthiness of Aircraft: Key Concepts

ICAO Definitions

• Aeroplane: Power-driven heavier-than-air aircraft deriving lift from aerodynamic reactions on fixed surfaces during flight.

• Aircraft: Any machine capable of deriving support in the atmosphere from reactions of air, excluding the earth’s surface reactions.

• Appropriate airworthiness requirements: Detailed codes established by a Contracting State for a particular aircraft, engine, or propeller.

• Approved: Accepted by a Contracting State for suitability for a specific purpose.

• Repair: Restoration of an aeronautical product to conform with airworthiness requirements.

• Satisfactory evidence: Documents or activities accepted by a Contracting State as sufficient for compliance with an airworthiness requirement.

• Type Certificate (TC): Document issued by a Contracting State certifying that a design meets specified airworthiness requirements.

• State of Design: Jurisdiction over the organization responsible for type design.

• State of Manufacture: Jurisdiction over organization responsible for final aircraft assembly.

• State of Registry: State where the aircraft is registered.

General Guidelines on Airworthiness

• Objective of Airworthiness: To ensure safety for passengers, crew, and people on the ground.

• Sections of Aircraft Airworthiness:

  • Type Certification (TC)

  • Continued Airworthiness (C/W)

• Responsibilities of State Authority: Define requirements and verify compliance for Type Certification.

• Maintenance Program: Agreement between manufacturer and authority to ensure Continued Airworthiness during the aircraft's life.

• Airworthiness Directives (AD): Mandatory instructions issued by the aviation authority to address specific safety issues and ensure ongoing compliance with airworthiness standards.

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When is an Aircraft Airworthy?

• Definition of Airworthy Aircraft: Conformity with type design and capable of safe operation.

• Criteria Maintaining Airworthiness:

  • Designed according to applicable requirements.

  • Built in conformity with approved design.

  • Operated within intended environment and limitations.

  • Maintained under procedures accepted by the responsible authority.

• Incident/Accident Tracking: Critical for maintaining safety and airworthiness. Includes reporting, analysis, corrective action setting, and implementation.

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ICAO Requirements and Principles

• Chicago Convention Articles:

  • Article 29: Aircraft must have Certificate of Airworthiness (CofA) issued by registration state.

  • Article 31: Requirements for CofA must meet or exceed ICAO standards.

  • Article 33: Recognition of CofAs issued by contracting states.

• Annex 8 of the Chicago Convention: Specifies SARP concerning aircraft airworthiness applicable to passenger, cargo, and mail transportation.

• Minimum Requirements in Annex 8: Approval of design and control of production.

Contents of Annex 8 and EU Requirements

• Annex 8 Structure:

  • Part I: Definitions

  • Part II: Procedures for Certification & Continuing Airworthiness

  • Part III: Large Aeroplanes

  • Additional Parts for Helicopters, Small Aeroplanes, Engines, and Propellers.

• References to EU Requirements:

  • Parts corresponding to Certification, Maintenance, and Licensing as per EU regulations.

Design Approval and Type Certification Process

• Design Approval: Often facilitated through organizational approval (ex: DOA for EU). Type design is foundational defining aircraft characteristics (drawings, processses, limitations…).

• Type Certificate Issuance Conditions:

  • Compliance with applicable airworthiness and environmental protection requirements.

  • No unsafe features.

  • Commitment to comply with ongoing airworthiness obligations.

• Production Oversight: May include a production organization approval (ex: POA for EU).

• Once the product has entered the production line, the applicant must demonstrate that the finished product complies with the state's airworthiness requirements: this leads to the issue of a Certificate of Airworthiness by the state of registry or in the EU the issue of the EASA Form 1 for products other than aircraft.

Certificate of Airworthiness (CofA)

• Eligibility for CofA: Justification of compliance with design requirements.

• CofA Issuance Process:

  • Renewed based on periodic checks as determined by state of registry.

  • Previous CofAs may support issuing in another state.

• Conditions of CofA Validity:

  • Continuous compliance with airworthiness requirements.

  • Maintenance by approved organizations.

• CofA Renewal Procedures: Ensured by regular inspections.

• Requirement for aircraft to have a CofA: Article 31: stipulates the need for all aircraft used for international navigation to be provided with a CofA issued or rendered valid by the State in which they are registered.

• Procedure for issuing certificates (EU 748/2012 and annex 8 Chap 3.2)

• EligibilityCriteria: Must comply with design, performance, and maintenance standards established by the relevant aviation authority.

• Classification: Aircraft are classified based on their design, intended use, and operational characteristics to ensure they meet specific airworthiness criteria.

  

• Application:

• CofA Application Requirements (Certificate of Airworthiness)

  📌 General Rules:

  • The application must follow the rules set by the competent authority of the Member State of registration.

  • It must specify the type of CofA or restricted CofA requested.

  🆕 For New Aircraft:

  • Certificate of Conformity (EASA-compliant)

  • For imported aircraft: declaration by the exporting authority confirming EASA design compliance

  • Weight and balance report with loading instructions

  • Flight manual, if required by airworthiness code

  🔄 For Used Aircraft:

  ✅ From a Member State:

  • Airworthiness review certificate

  🌍 From a non-Member State:

  • Statement on the airworthiness status from previous State (issued within 60 days)

  • Weight and balance report + loading instructions

  • Flight manual (if required)

  • Maintenance and production records

  • Recommendation for issuing CofA or restricted CofA + airworthiness review certificate

  🌐 Language Requirements:

• All manuals, lists, brochures, and instrument markings must be in at least one official EU language, accepted by the competent authority.

Amendment or change:

A CofA may be amended or changed only by the competent authority of the Member State of registration. Conditions for transfer and reissue in Member States:

• if, when the ownership of an aircraft has changed, it remains on the same register, the CofA or restricted CofA, complying with the restricted type-certificate, shall be transferred with the aircraft;

• if the aircraft is registered in another Member State, the CofA or restricted CofA, complying with the restricted type-certificate, shall be issued upon submitting of the former CofA and a valid airworthiness review certificate;

• when the ownership of an aircraft has changed and the aircraft has a restricted CofA not complying with a restricted type-certificate, CofAs must be transferred with the aircraft, provided that the aircraft remains on the same register, or be issued only with the official authorization from the competent authority of the Member State of registration where it is transferred.

Inspections:

• At the request of the competent authority of the Member State of registration, the holder of the CofA shall provide access to the aircraft for which this certificate of airworthiness has been issued.

Valilidity period and continuation:

Validity period and continuation: A CofA shall be issued for an unlimited period and remains valid subject to the following conditions:

• compliance with applicable continuing airworthiness and type design requirements;

• the aircraft remains on the same register;

• the type certificate or restricted type-certificate has not been invalidated;

• the certificate has not been suspended or withdrawn.

• In the event of suspension or withdrawal, the certificate must be returned to the competent authority of the Member State of registration.

Aircraft identification: Aircraft identification All applicants for a CofA must show that their aircraft is identified (identification of aircraft products, parts and equipment)

temporary loss of airworthiness: If an aircraft is not maintained in an airworthy condition in accordance with the applicable airworthiness regulations, the aircraft may not be operated until it has been restored to an airworthy condition.

Case of a damaged aircraft:

1. Responsibility
– The State of registration decides if the aircraft is still airworthy.

2. Damage Abroad
– If damage occurs in another Contracting State:
 • That State can prevent the aircraft from flying.
 • It must inform the State of registration and send full details.

3. If Not Airworthy
– The State of registration must forbid the aircraft from flying.
– Flight only possible after restoration of airworthiness.

4. Exception
– The State of registration may allow a non-commercial flight with special operating conditions to a place where repairs can be done.

5. If Still Airworthy
– The aircraft can resume its flight.

Continued Airworthiness

• Objectives of Continued Airworthiness:

  • Verify safety after aircraft modifications or repairs.

  • Maintain compliance with approved Type Design and regulatory standards.

• Actions Post-Incident: Include thorough checks, authority notifications, and possibly limitation on operations pending airworthiness restoration.

• Renewal of Certificate of Airworthiness – Summary for Mind Map

  1. Responsibility
  – The State of registry is responsible for renewal of the certificate.
  – Goal: Keep the certificate valid.

  2. Conditions
  – All changes and repairs must be approved.
  – Maintenance must be done by an approved organization with qualified staff.

  3. Limited-Period Certificates
  – The State of registry performs periodical inspections for renewal.

  4. Unlimited-Period Certificates (EASA Member States)
  – Periodical inspections are done by an approved organization.
  – This organization is regularly audited by the State of registry.

• Final Summary of Airworthiness Process:

  • Initial TC leads to production and issuing of CofA.

  • Continued airworthiness maintained through regular inspections and compliance checks throughout the aircraft’s service life.