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Project AS 08/19 - Subpart 91U - Navigation Authorisations for Australian Operators - Post Implementation Review and Update
Subpart 91U was issued in December 2005. It was developed to provide a head of power for all types of navigation authorisations issued by CASA. Currently, Subpart 91U only provides legislative backing for RNP 10 and 4, although 'placeholders' were included to accommodate other navigation specifications. Subpart 91U is now due for Post-Implementation Review (PIR).
Also, ICAO has just developed the Performance Based Navigation (PBN) concept which provides an internationally agreed common framework for navigation specifications and addresses any inconsistencies in the way States may have implemented navigation specifications and authorisations.
Now is an opportune time to conduct the Subpart 91U PIR and at the same time incorporate the latest ICAO PBN navigation specifications - before Australian operators become disadvantaged in their operations in other States that have implemented PBN.
The estimated time within CASA to draft, educate and promote this project is 12 months. Legal drafting by the Office of Legal Drafting and Publishing (OLDP) is additional.
Consequences of NOT proceeding with this project include that:
- CASA will have failed to act on a recent resolution of the ICAO Assembly requiring States to implement PBN; and
- By exclusion, Australian operators could be re-routed to less efficiently managed routes and levels which could impact safety and efficiency.
ICAO Annex 6 states that operators must obtain an 'operational approval' from the State of Registry or State of the Operator before undertaking Required Navigation Performance (RNP), Reduced Vertical Separation Minimum (RVSM) or Minimum Navigation Performance Specification (MNPS) operations. RNP and RVSM approvals are required not only for operations in international airspace but also in sovereign airspace.
These navigation requirements are usually put into affect through ICAO Regional Supplementary Procedures (e.g. MNPS for the North Atlantic and Basic Area Navigation (B-RNAV) for parts of European airspace).
CASA has used a variety of means to approve/authorise operators. For example, it has used ICAO regional supplementary procedures as a basis for RNP 10 authorisations, and CAR 179A as a regulatory head of power for GPS RNAV approvals, and, more recently, for Precision RNAV (P-RNAV) approvals for operations in Europe.
Subpart 91U was developed to provide a head of power for all types of navigation authorisations issued by CASA. An NPRM was issued in July 1994 and a NFRM in November 2005. The new regulations were issued in December 2005. However, Subpart 91U currently only provides legislative backing for RNP 10 and 4, although 'placeholders' were included to accommodate other navigation applications.
Also, ICAO has just developed the Performance Based Navigation(PBN) concept which provides an internationally agreed common framework for navigation specifications and addresses any inconsistencies in the way States may have implemented navigation specifications and authorisations.
Delaying incorporation of the PBN navigation specifications into Australian regulations could, in the near future, severely disadvantage Australian operations in other States that have implemented PBN. In some cases Australian operators may even be excluded from parts of airspace overseas, requiring them to follow less efficiently managed routing and levels which could impact safety as well as operating efficiency. If CASA delays regulating for the new navigation specifications Australia will have failed to take full advantage of the significant airspace, operational and ATC gains to be had with implementing the PBN concept.
The proposed project is meant to conduct a PIR of Subpart 91U and, at the same time, provide a re-write and 'catch-all' function for the currently used navigation approvals specified in CARs as well as those in the new ICAO PBN manual. Additionally, some older navigation specifications, such as AUSEP, appear to have been removed from regulations and are currently only mentioned in AIP. These specifications - including establishing the relationship between navigation specifications and separation standards - will also be included in the PIR/re-write.
The list of anticipated specifications and standards for the updated regulation would include the following specifications and standards:
- GPS RNAV,
- GPS OCEANIC,
- RNP 10 (RNAV 10),
- RNAV 5,
- RNAV 2
- RNAV 1
- RNP 0.3
- Advanced RNP
- RNP 4
- RNP 1
- RNP APCH
- RNP AR Operations
In addition to setting regulation, the auditing processes and entry control methods will require updating. As these processes and methods are conducted by other branches of CASA, the project will also assist the ATOG, GAOG and INT Branches to:
- update existing entry control and audit processes;
- update and maintain a national database for navigation approvals utilising AIRS, and
- Reissue operators holding "old" authorisations with new authorisations under the amended Subpart 91U.
CASR Part 91 Subpart U
The PBN rules were initially issued in CAO 20.91 on 13 July 2012 but with placeholders for navigation specifications where the development within the ICAO PBN Study Group was not complete. CAO 20.91 is being revised to add the navigation specifications not included in the original issue.
As a result of the revision, requirements contained in CAO 20.18 clause 9A have been superseded by PBN requirements contained in CAO 20.91. A consequential revision to CAO 20.18 is required to delete the superseded requirements of clause 9A and update the terminology in clauses 9D.3 (e), 9D.5 (e) and 9D.8 (e) to reflect PBN requirements.
After the revised CAO 20.91 is published, the Part 91U MOS will be drafted and a PIR carried out on the complete navigation authorisations regulatory regime. Findings from the PIR will be incorporated into the Part 91U MOS.
This project was approved by Peter Cromarty, GGM, AARG on 31 October 2008
Project sponsor: firstname.lastname@example.org
Project Leader: email@example.com
Standards Development project manager: firstname.lastname@example.org
|Consultation updates in 2015|
|Draft AC 91.U-04 v1.0 - Airworthiness requirements for performance based navigation||All comments should be sent to the Project Leader, email@example.com by close of business 21 January 2015.||7 Jan 2015|
|NFRM 1320AS - Navigation authorisations||This NFRM has been published.||6 Jan 2015|
|Consultation updates in 2014|
|NPRM 1320AS – Navigation authorisations||Comments to this NPRM closed 22 August 2014.||25 Aug 2014|
|NPRM 1320AS – Navigation authorisations||Comments close 22 August 2014.||2 Jul 2014|
|Consultation updates in 2012|
|NFRM 1002AS - Navigation Authorisations - Amendments to Civil Aviation Order (CAO) 20.91||This NFRM has been published.||24 Sep 2012|
|CAAP 181A-1(2) – Reduced Vertical Separation Minimum (RVSM) Approvals||This CAAP has been published.||16 Aug 2012|
|Addendum to NPRM 1002AS - Navigation Authorisations||
All comments should be sent to the Project Leader at firstname.lastname@example.org, by close of business Monday 7 May 2012.
Note: NPRM 1002AS was released 29 July 2011.
|23 Apr 2012|
|Consultation updates in 2011|
|NPRM 1002AS - Navigation Authorisations||The NPRM is open for comment and is available on the CASA website. Comment period closes 23 September 2011.||29 Jul 2011|
|Consultation updates in 2008|
|Project AS 08/19 - Subpart 91U - Navigation Authorisations for Australian Operators - Post Implementation Review and Update||New project approved on 31 October 2008||31 Oct 2008|