The Combined Airworthiness Organisation — why it exists
Before 2025, a small flying club or private operator of a light aircraft needed a CAR-M Subpart F maintenance approval and a Subpart G CAMO approval — two organisations built for airlines. CAR-CAO (Issue 1, 31 July 2024, effective 1 January 2025) gives such operators one lighter approval that can cover maintenance, continuing airworthiness management, or both.
A CAO may maintain and manage the continuing airworthiness of aircraft (and components for them) that are not complex motor-powered aircraft and are not listed in an Air Operator Certificate issued under Rule 134 and Schedule XI. An airline's aircraft can never be looked after by a CAO — they need CAR-CAMO and CAR-145.
| CAR-145 | CAR-CAMO | CAR-CAO | |
|---|---|---|---|
| What it does | Maintenance | Continuing airworthiness management | Maintenance and/or CAW management |
| Aircraft | All types and operations | All types and operations | Non-complex, not in an AOC |
| Exposition | MOE | CAME | CAE — Combined Airworthiness Exposition |
| Oversight system | SMS + compliance monitoring | SMS + compliance monitoring | Quality system + organisational review |
CAR-CAO requirements in brief
- Application (CAO.A.015) on CA Form 2 (or acceptable equivalent).
- Terms of approval (CAO.A.020) — the scope is in the CAE. For aeroplanes above 2 730 kg MTOM and helicopters above 1 200 kg MTOM or certified for more than 4 occupants, the scope must list the particular aircraft types; for complete turbine engines, the manufacturer/series/type or tasks.
- Combined Airworthiness Exposition (CAO.A.025) — the organisation's manual, approved by DGCA.
- Facilities (CAO.A.030), components, equipment and tools (CAO.A.050), maintenance data and work orders (CAO.A.055), maintenance standards (CAO.A.060).
- Personnel (CAO.A.035) — an accountable manager with authority to finance all activities; nominated person(s) responsible for compliance (AMC: 5 years' aviation experience, 2 of them in industry); sufficient qualified staff (temporarily subcontracted staff allowed); qualifications assessed and recorded; welding and NDT (other than colour-contrast) staff qualified to recognised standards.
- Certifying staff (CAO.A.040) — comply with CAR-66 and 66.A.20(b), and understand the aircraft and procedures. A one-off certification authorisation for an aircraft grounded away from base may go to an employee with similar type qualifications, or to a person with at least 3 years' maintenance experience and a valid ICAO licence rated on type (if no CAO is at that location) — reported to DGCA.
- CRS — aircraft (CAO.A.065) and component (CAO.A.070, normally CA Form 1).
- Continuing airworthiness management (CAO.A.075/080) where that privilege is held.
- Records (CAO.A.090) — maintenance records retained 3 years from the release; CAW management records per M.A.305 / ML.A.305.
- Quality system (CAO.A.100) — a quality manager; monitoring of activities, contracted tasks and compliance; monitoring records kept at least 2 years. A small CAO (only CAR-ML aircraft, or not more than 10 full-time maintenance staff, and so on) may use an organisational review instead.
- Changes (CAO.A.105), continued validity (CAO.A.110), findings (CAO.A.115).
Privileges — CAO.A.095
- Maintenance: maintain approved aircraft/components at approved locations; arrange specialised services at other qualified organisations under its control; maintain at any location when needed because of unserviceability or occasional maintenance; issue CRS.
- Continuing airworthiness management: manage the CAW of aircraft for which it is approved; subcontract limited CAW tasks to organisations working under its quality system (the CAO remains accountable).
- A CAO may be approved for one or more of these privileges.
- One-off authorisation experience: 3 years under CAR-CAO, 5 years under CAR-145.
- CAO cannot be used for complex motor-powered aircraft or aircraft on an AOC.
- Existing CAR-M Subpart F organisations for non-complex, non-AOC aircraft transitioned to CAR-CAO by 31 July 2026 (AAC 4 of 2024).
CAR-147 — maintenance training organisations
Training organisations are approved under Rule 133B. DGCA publishes two CARs:
| CAR-147 (Basic) | CAR-147 (Type) | |
|---|---|---|
| Purpose | Approved basic training for CAR-66 categories — reduces the experience needed (e.g. B1.1 from 5 to 2 years) | Aircraft type training and task training for type ratings |
| Issue | Issue 1, 27 Dec 2017 | Issue 1, 19 Sep 2014 (Rev 1) |
| Approval certificate | CA Form 11A | CA Form 11 |
| Certificate to student | Certificate of Recognition — CA Form 148 | Certificate of Recognition — CA Form 149 |
Common requirements
- Accountable manager; a training manager, examination manager and quality manager (post-holders nominated on CA Form 4); sufficient instructors, knowledge examiners and practical assessors. A manager who also teaches may not examine in subjects they delivered.
- Instructors, examiners and assessors receive updating training every 24 months (at least 35 hours for the basic organisation), with records kept.
- Facilities: classrooms, practical workshops, examination rooms where no candidate can read another's work.
- Maintenance Training Organisation Exposition (MTOE), with a statement signed by the accountable manager; approved by DGCA.
- Examinations: examination staff keep all questions secure; a student caught cheating is barred.
- Approval valid for up to 5 years (Rule 133B).
CAR-147 (Basic) numbers
| Course | Minimum duration | Theory ratio |
|---|---|---|
| A1, A3, A4 | 800 hours | 30–35% |
| A2 | 650 hours | 30–35% |
| B1.1, B1.3, B1.4, B2 | 2 400 hours | 50–60% |
| B1.2 | 2 000 hours | 50–60% |
| B3 | 1 000 hours | 50–60% |
- Maximum 30 students in a knowledge-training class; at most two batches per category per year.
- Student participation of at least 90% of tuition hours.
- At least 30% of practical training in an actual maintenance working environment.
- The approval may be withdrawn or limited if no batch has been inducted for two consecutive years.
- AAC 2 of 2018 gives the approval and renewal procedure; AAC 1 of 2021 and AAC 4 of 2020 cover distance learning.
Foreign organisations — Rule 133BA
ICAO makes the State of Registry responsible for approving maintenance organisations that work on its aircraft. Rather than have every foreign shop hold a full DGCA approval, Rule 133BA lets the DG accept an organisation already approved by a competent foreign authority. An acceptance is valid for up to 2 years, renewable 2 years at a time.
| FAMO — Series E Part XI | FAO — Series E Part XII | |
|---|---|---|
| What | Foreign Approved Maintenance Organisation | Foreign Approved training Organisation — aircraft type training |
| Must hold | FAA Part 145 repair station and/or EASA Part-145 approval | EASA Part-147 approval (not applicable to such organisations located in India) |
| Scope | Indian-registered aircraft and components (engines, APUs), limited to the FAA/EASA scope plus a DGCA Supplement | Type training for endorsement on a CAR-66 licence |
| Documents | DGCA Supplement to the MOE; Certificate of Acceptance | DGCA MTOE Supplement; application on DGCA Form FM 2; evidence of an Indian customer |
For transit and extended-transit inspections abroad for Indian operators, an organisation approved by the local civil aviation authority may be accepted under AAC 5 of 2018.
Fuel, lubricant and special product organisations — Series E Part VI
Organisations engaged in bulk storage, compounding, blending, testing, distribution or supply (including fuelling and defuelling) of aviation fuels, lubricants and special products must hold a Certificate of Approval under Rule 133B before operating. Approval categories: aviation fuelling stations, terminals/depots, refineries, testing laboratories and on-wheel facilities. The organisation has an accountable manager with corporate authority to finance and carry out the approved tasks.
Chapter summary
- CAR-CAO = one approval for maintenance and/or CAW management of non-complex aircraft not on an AOC; manual = CAE; quality system; records 3 years, quality records 2 years; one-off authorisation needs 3 years' experience.
- Type listing needed for aeroplanes above 2 730 kg and helicopters above 1 200 kg or more than 4 occupants.
- CAR-147 Basic: B1.1/B1.3/B1.4/B2 2 400 h, B1.2 2 000 h, B3 1 000 h, A 800 h (A2 650 h); max 30 per class; 90% attendance; CA Form 148. Type training certificate CA Form 149.
- Rule 133BA acceptance (2 years): FAMO holds FAA/EASA Part-145; FAO holds EASA Part-147.
- Fuel organisations need Series E Part VI approval before handling aviation fuel.