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Under development
CASR Part 121 – Australian Air Transport Operations - Large Aeroplanes

Parts 121, 133 and 135 of the new Civil Aviation Safety Regulations (CASRs) all deal with a range of passenger and/or cargo operations - Part 121 is for large aeroplanes, 135 for small aeroplanes, and 133 for rotorcraft.

The proposed regulations in Part 121 will set the minimum acceptable standards applicable to large aeroplanes that are conducting passenger or cargo transport operations:
An Air Transport Operation means an operation in an aircraft:

  • That is conducted for hire or reward or is otherwise publically available and
  • That is a passenger transport operation or a cargo transport operation.
  • A passenger transport operation is a transport operation in an aircraft involving the carriage of passengers, whether or not cargo is carried on the aircraft. A passenger transport operation does not include, cost sharing operations, aerial work operations or an operation for the carriage of passengers in an aircraft with a certificate of airworthiness other than a standard certificate of airworthiness.

"Large aeroplanes" in Part 121 means an aeroplane:

  • fitted with more than 9 passenger seats in its approved configuration, or
  • with a maximum take-off weight (MTOW) of more than 8618 kg.
Part 121 will consolidate into one Part of the new CASRs the regulatory requirements that will apply in addition to, or in substitution for, the general operating and flight rules prescribed in Part 91, when using larger aeroplanes for air transport operations.

The Part will replace all affected Civil Aviation Regulations 1988 (CAR) and Civil Aviation Orders (CAO) and will integrate with the rules in the other CASRs, principally Parts 91 and 119. It will largely cover the same regulatory areas as now but with new rules, mostly to give effect to the current and recently revised International Civil Aviation Organization (ICAO) Annex 6, Part I standards and recommended practices (SARPs) not currently incorporated.

In 1999, CASA was directed to "minimise the distinction between Charter and Regular Public Transport (RPT) operators". To address this, Part 121 will set in place a common level of safety for operators who are authorised to provide an Air Transport Operation, an amalgamation of current Charter and RPT operations and standards - in order to carry Passengers in large aeroplanes. The safety level applies irrespective of whether an operation is scheduled or non-scheduled as described by ICAO in Part I of Annex 6.

Who Part 121 affects:

  • Air Operators involved in current Charter and RPT operations (passenger and cargo) in aeroplanes.
  • Personnel including flight crew members, cabin crew, ground and support personnel involved in the operation of aeroplanes engaged in Charter or RPT (passenger and cargo) operations and the travelling public.

Key proposals

  • Single standard to be introduced for Passenger Transport Services regardless of whether Charter or RPT operations are involved;
  • Part 121 flights to be planned and operated under the IFR only;
  • Simplified performance regulations in accordance with ICAO;
  • Up-dated requirements for FDRs and CVRs and the introduction of a requirement for the fitting of an underwater locating device on long overwater flights.
  • Re-introduction of the requirement for first aid kits and a new requirement for emergency medical kits and universal precaution kits on specified flights;
  • Allowing up to 30 minutes without a requirement for Flight Crew supplemental oxygen above 10,000 feet (up to FL130) for unpressurised aircraft;
  • Flight and cabin crew members to be subject to more comprehensive training and checking requirements, including Human Factors training;
  • Cabin crew to passenger seat ratio 1:50
  • A greater focus on outcome based recency requirements rather than just prescriptive rules for flight crew;
  • Alternative training and checking programs to allow operators to structure their own training and checking programs relevant to their fleets and flight crew;
  • Restrictions to be placed on the crewing together of inexperienced pilots;
  • Restrictions for flight crew on the number of different types operated on;
  • Additional requirements for cabin crew recency, pre-flight briefings and triennial recurrent training;
  • More comprehensive provisions for:
    • fuel based on ICAO Annex 6 Amendment 36 with the ICAO Flight Planning and Fuel Management Manual (FPFMM) as the foundation guidance material;
    • alternate aerodrome requirements, and operational flight planning based on ICAO Annex 6 Part I standards;
    • EDTO provisions in accordance with ICAO Annex 6 Attachment D;
    • low visibility operations, including the use of Enhanced Vision Systems (EVS) and Head Up Display (HUD) ;
    • PBN new approach classifications;
    • standard passenger and baggage weights (checked baggage to be weighed, baggage placement limits; operators provided with the means to establish standard weights, or different standard weights, to those legislated);
    • Relief flight crew members including Cruise Relief co-pilots; and
    • Narrow runway operations.

Part 121 operator's will require certification under CASR Part 119, with its requirements for: continuing airworthiness under an approved aircraft maintenance program, operational risk management under a safety management system, fatigue risk management systems for crew, and procedural training and checking of flight crews under the operator's training and checking system either in-house or provided by an arrangement with a Part 142 certified training and checking provider.

Project management

Project Leader: Miles Gore-Brown

Standards Officer: Miles Gore-Brown, Steven Campbell

Project Sponsor: Peter Boyd, Executive Manager Standards Divisionn


View the CASR Part 121 history.

Current projects

OS 14/08 – Categorisation of aeroplane and helicopter 'ambulance function' flights as Air Transport Operations

Standards Consultative Committee (SCC)

Operational Standards Sub-committee.