Chapter 8: Certification of Aircraft, Parts and Appliances

Initial airworthiness in one sentence

Before an aircraft can be continuously maintained, its design must be approved (type certificate), each aircraft must be built to that design (production), and it must be found airworthy and registered (certificate of airworthiness, certificate of registration). In India the legal base is Rules 49 to 50 of the Aircraft Rules and the detailed procedures are in CAR-21 (Section 6 Series B; Issue II, Rev 8, July 2025), harmonised with EASA Part-21.

Type certificates in the Aircraft Rules — Rules 49 to 49I

CAR-21 at a glance

Failures, malfunctions and defects — 21.3A

Holders of a TC, restricted TC, STC, ITSO authorisation or major repair design approval must run a system to collect, investigate and analyse failures, malfunctions and defects, and must report to DGCA any that have resulted, or may result, in an unsafe condition — as soon as practicable and not later than 72 hours after identifying the possible unsafe condition.

Airworthiness directives — 21.3B

• An AD is a document issued or adopted by DGCA that mandates actions on an aircraft to restore an acceptable level of safety.
• DGCA issues one when an unsafe condition exists in an aircraft (from a deficiency in the aircraft, engine, propeller, part or appliance) and is likely to exist or develop in other aircraft.
• The design holder proposes the corrective action and provides accomplishment instructions to operators.
• An AD contains at least: the unsafe condition, the affected aircraft, the required actions, the compliance time and the date of entry into force.

Changes to the type design — 21.91

Repairs — Subpart M

A repair is the elimination of damage and/or restoration to an airworthy condition after initial release into service. Eliminating damage simply by replacing parts without design activity is a maintenance task and needs no approval under CAR-21.

The certificate of airworthiness

Classification and application

• 21.173: a certificate of airworthiness is issued to aircraft conforming to a type certificate; a special certificate of airworthiness to aircraft conforming to a restricted TC or shown to comply with specific airworthiness codes ensuring adequate safety.
• Application on form CA-25; the aircraft must be identified per Subpart Q.
• For an imported aircraft, the export C of A from the State of manufacture should not be issued more than 60 days before the application for validation.

Categories (CAR Sec 2 Series F Part III, Appendix C)

An aircraft may only be used in the sub-divisions for which it is certified (the most stringent maintenance programme applies if certified in several). Private aircraft may not be used for hire or reward. State Government aircraft are certified Normal–Passenger.

Validity — the C of A and the ARC

The C of A does not carry a fixed expiry date; it remains valid while (CAR Sec 2 Series F Part III §4.1):

1. the Airworthiness Review Certificate is valid (Rule 50(5));
2. all due maintenance per the maintenance programme is completed;
3. all ADs and mandatory modifications are complied with;
4. modifications and repairs conform to the regulations;
5. every technical log discrepancy is actioned and certified;
6. all releases to service are completed and certified;
7. component lives are within limits;
8. weight and balance data are accurate and within TC limits;
9. the flight manual is current;
10. documents and safety equipment on board are in order; and
11. a general condition inspection is satisfactory.

It also depends on the aircraft remaining on the Indian register and its TC remaining valid (21.181). A C of A is deemed suspended under Rule 55 (major damage, major defect, unapproved modification…). On surrender or revocation, it is returned to DGCA.

Special C of A and special flight permits

Special C of A — Series F Part XXIII

Issued for aircraft holding a restricted TC (issued, validated or recognised under Rules 49/49A, 49B or 49E) or whose design standard is accepted under Rule 49I (for example light sport and similar aircraft). It is valid for the period stated in it and renewable by the DG (Rule 50(6)).

Special flight permit — CAR-21 Subpart P, Series F Part VII, Rule 55A

Issued to an aircraft that does not meet (or has not been shown to meet) airworthiness requirements but is capable of safe flight under defined conditions. The 17 purposes in 21.701 include:

• development, showing compliance, design/production organisation crew training, production flight testing, flights between production facilities, customer demonstrations;
• delivery or export, DGCA acceptance flights, market survey, exhibitions and air shows;
• ferrying to a place where maintenance, repair or an airworthiness review will be performed, or to storage, when the C of A is suspended or deemed suspended;
• flight at weight above MTOW for extra fuel/tanks/navigation equipment on long over-water or remote flights;
• record-breaking and racing; flight before environmental conformity is shown; non-commercial flying of individual non-complex aircraft for which a C of A is not appropriate; evacuation from impending danger; flights under modification or repair.

Noise certificate — CAR-21 Subpart I, CAR Sec 6 Series C Part II

Noise certification follows ICAO Annex 16, Volume I. A document attesting noise certification must be carried on board (Series X Part VII).

Registration — CAR Sec 2 Series F Part I

• Rule 5: no one may fly an aircraft unless it is registered and bears its nationality and registration marks and the owner's name (Rule 37).
• The CAR details application, categories A and B (Rule 30), the C of R contents and validity (for a leased aircraft, limited to the lease period), change of ownership and de-registration.
• India acceded to the Cape Town Convention (31 March 2008): an IDERA (Irrevocable De-registration and Export Request Authorisation) holder can request de-registration and export (Rule 32A).
• Identification uses a fireproof plate (a material that withstands heat at least as well as steel).

Modifications and repairs — who approves the data?

Major repair (AAC 1 of 2017): might appreciably affect structural strength, performance, powerplant operation, flight characteristics or other qualities affecting airworthiness or environmental characteristics; a minor repair is any other. Major modification: a change to type design with an appreciable (more than negligible) effect on mass and balance limits, structural strength, engine operation, flight characteristics, reliability or operational characteristics.

Parts and appliances — CA Form 1

21.307: no part or appliance (except a standard part) is eligible for installation in a type-certificated product unless it is accompanied by an authorised release certificate — CA Form 1 — certifying it airworthy, and is marked per Subpart Q. The same form is used by maintenance organisations as the component CRS (145.A.50). Parts made under a POA or ITSO authorisation are released on CA Form 1 as new parts.

Chapter summary

• Rules 49–49I: TC, RTC, validation (49B), recognition (49E), STC (49F/G), design acceptance (49I).
• CAR-21: 21.3A reporting within 72 h; 21.3B AD content (unsafe condition, aircraft, actions, compliance time, effective date); minor vs major change; only the TC holder gets major changes under Subpart D, others need an STC.
• C of A for TC'd aircraft, special C of A for RTC/accepted designs; application CA-25; categories Normal (5 sub-divisions), Special, Aerobatic.
• C of A stays valid with a valid ARC plus maintenance, AD, mod, defect and document conditions; export C of A within 60 days.
• Special flight permit for aircraft capable of safe flight under conditions — e.g. ferry to maintenance.
• Rule 52: manufacturer data deemed approved; other data approved by DGCA (Sec 6 Series A Part V). Parts need CA Form 1 (except standard parts).