Explanatory Statement
Civil Aviation Regulations 1988
Instructions — use of RNAV (GNSS) approaches by RNP-capable aircraft
Legislation
Section 98 of the Civil Aviation Act 1988 (the Act) provides that the Governor-General may make regulations for the Act and in relation to the safety of air navigation.
Under subregulation 179A (1) of the Civil Aviation Regulations 1988 (CAR 1988), CASA may issue instructions in relation to Instrument Flight Rules (I.F.R.) flights specifying the method by which an aircraft is to be navigated and how a positive position fix is to be obtained.
ICAO rule changes
It is Australian aviation policy that instrument flight procedures should conform to the International Civil Aviation Organisation (ICAO) design rules (ICAO Document 8168, commonly referred to as PANS‑OPS). RNAV (GNSS) approach means an area navigation instrument approach procedure. Approximately 450 RNAV (GNSS) approaches designed in accordance with PANS‑OPS have been commissioned at 260 aerodromes across Australia. Those procedures are designed to be flown by aircraft equipped with self-contained GPS receivers.
However, most modern Australian turbo‑jet airline aircraft are equipped with computerised flight management systems (FMS) that are more sophisticated than the Global Navigation Satellite System (GNSS) navigation equipment. Such aircraft use GNSS positioning to update multiple inertial reference systems (IRS) employing self‑contained laser guided gyroscopes. These navigation systems are designed to comply with Required Navigation Performance (RNP) standards, and the operating procedures and cockpit displays are related to the RNP capability of the aircraft rather than to a specific GNSS receiver used by other less sophisticated aircraft.
The instrument contains procedures to allow for the conduct of RNAV (GNSS) approaches by Qantas Airways Limited (Qantas) in Airbus A380 aircraft capable of RNP 0.30 performance (the specified aircraft). The RNP capability of an aircraft is specified in the aircraft’s flight manual (AFM) and displayed to the flight crew by the FMS.
RNAV (GNSS) approach procedures provide improvements in safety by allowing runway‑aligned straight-in approaches, the use of automated flight systems, and vertical navigation. The instrument allows RNP 0.30‑capable aircraft to use existing RNAV approach procedures, thereby providing straight-in approach capability at almost every runway in Australia. This offers a significant safety benefit to those operations.
Conditions and procedures
The instrument sets out the conditions to be satisfied by Qantas and its specified aircraft for the approval to apply, and the procedures to be followed, during an RNAV (GNSS) approach.
For example, the AFM must expressly state that the aircraft is capable of meeting the requirements of RNP 0.30. RNAV must not be used to satisfy the requirements of alternate aerodrome planning, or used as a navigation reference for certain flights. The aircraft must be operated in accordance with the manufacturer’s instructions. Although not required to be expressly stated, as a matter of law the flight crew must also comply with the relevant instrument rating requirements under Civil Aviation Order 40.2.1, and with the approved tests and checks under the training and checking organisation requirements in regulation 217 of CAR 1988.
Under the procedures, the pilot in command must ensure that RNAV (GNSS) approaches are flown in accordance with authorised instrument approach procedures validated by the operator. The pilot in command must ensure that a vertical approach path remains above the vertical limitations published in the approach chart. The pilot in command must discontinue the approach if an RNP of 0.3 cannot be maintained from the final approach fix.
Legislative Instruments Act
Subregulation 179A (3A) of CAR 1988 declares instructions to be a disallowable instrument. Under subparagraph 6 (d) (i) of the Legislative Instruments Act 2003 (the LIA), an instrument is a legislative instrument for section 5 of the LIA if it is declared to be a disallowable instrument in legislation in force before the commencement of the LIA. The instructions are, therefore, a legislative instrument and are subject to tabling and disallowance in the Parliament under sections 38 and 42 of the LIA.
Consultation
Consultation under section 17 of the LIA has not been undertaken in this case. The instrument renews a previous instrument issued to the same operator (CASA 05/09) which expires at the end of January 2011. In accordance with the ICAO standard, a similar instrument would be issued to any operator whose relevant aircraft can meet these exacting standards of navigation performance and are expressly endorsed as such by their manufacturer.
The instrument commences on 1 February 2011 and stops having effect at the end of January 2013.
The instrument has been made by a delegate of CASA under subregulation 7 (1) of CAR 1988.
[Instrument number CASA 18/11]