Explanatory Statement
Civil Aviation Regulations 1988, Civil Aviation Order 20.7.1B
Amendment of instrument CASA 19/06 — Instructions – RNAV (RNP-AR) approaches and departures
Legislation
Section 98 of the Civil Aviation Act 1988 (the Act) provides that the Governor-General may make regulations for the Act and the safety of air navigation.
Under subregulation 178 (1) of the Civil Aviation Regulations 1988 (CAR 1988), the pilot in command of an aircraft must not fly along a route segment at a height lower than the published lowest safe altitude (LSALT) for that segment. Under subregulation 178 (2), if there is no LSALT, the pilot must not fly lower than the LSALT calculated by a method determined by CASA.
However, paragraph 178 (4) (c) provides an exemption from these requirements if the flight is during a published authorised instrument approach procedure (IAP) or a published authorised instrument departure procedure (IDP) designed by a certified designer.
Under subregulation 179A (1), 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 when in such flight.
Legislative instrument CASA 19/06 was issued to enable a controlled, Australia-wide, trial by Qantas Airways Limited (Qantas) of certain Area Navigation (Required Navigation Performance‑Authorisation Required) instrument approach and departure procedures (RNAV (RNP-AR) IAP and IDP) designed by Naverus Inc (Naverus). These are sophisticated, computed assisted area navigation operations with particular performance requirements for which CASA authorisation is required. Qantas is the participant in this trial.
Instructions for trial operation
The instrument enables the trial to take place in controlled circumstances by issuing instructions under subregulation 179A (1) on how an aircraft is to be navigated in I.F.R. flight, in the course of the trial, when using RNAV (RNP-AR).
Approval
Subregulation 5 (1) of CAR 1988 provides that where CASA is authorised to issue directions, it may do so in the form of Civil Aviation Orders (CAOs).
Subregulation 235 (2) of CAR 1988 authorises CASA to issue directions setting out the manner of determining a maximum weight for an aircraft that its gross weight must not exceed at take-off or landing.
For aircraft of a maximum take-off weight exceeding 5 700 kg, CASA has issued such directions in the form of Civil Aviation Order 20.7.1B (CAO 20.7.1B).
Subsections 12 and 12A of CAO 20.7.1B provide for methods of meeting take-off obstacle clearance requirements in relation to take-off weight limitations by reference to the definition of the take-off area. Under subparagraph 12.1.1 (b) and paragraph 12A.5, the limitation of the take-off area is redefined for approved RNP operations, in RNP‑capable aeroplanes that are approved for area navigation (RNAV) using specified RNP containment values.
Therefore, to enable departures during the Qantas trial to continue to take advantage of these RNP-AR‑related obstacle clearance provisions, the instrument also contains, under the provisions of CAO 20.7.1B:
(a) an approval of Boeing 737-800 aeroplanes for area navigation (RNAV); and
(b) an approval of the trial as an approved RNP operation; and
(c) specification of the RNP containment appropriate for the RNP type selected in the operations.
Exemption from publishing procedures
Because what is proposed is a specialised trial only, and because of exemptions and conditions applying to its procedure design certificate, Naverus does not publish its IAP and IDP. To ensure that the trial is conducted in accordance with the requirements of the LSALT exemption provided by paragraph 178 (4) (c), it is necessary, by means of an exemption under subregulation 308 (1), to exclude the requirement to publish IAP and IDP.
Reason for amendment
The instrument applies to all RNAV (RNP-AR) approaches and departures in I.M.C. under the I.F.R. in Australia that are conducted in accordance with the “Qantas proposal accepted by CASA”. The original instrument defined Qantas proposal as the proposal contained in the document titled Qantas B737-800 RNP RNAV Implementation Australian Airports version 1.2 issued December 2005. That document did not include a reference to Brisbane aerodrome. As a result, the expansion of the trial to cover Brisbane has required that the definition be amended. The amendment removes the reference to a particular version of the document. The amended definition allows alteration of the document provided that it is done with the approval of CASA.
Legislative Instruments Act
Subregulation 179A (3A) of CAR 1988 declares that instructions not in the form of a CAO are 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 CAO amendment will not substantially alter existing arrangements and is regarded as being of a minor or machinery nature.
The instrument commences on the day after it is registered. The original instrument as amended stops having effect at the end of 31 January 2008.
The instrument has been made by the Director of Aviation Safety, on behalf of CASA, in accordance with subsection 84A (2) of the Act.
[Instrument number CASA 433/06]