Consultation draft - transition of ATSOs and CAO 101.55 into the Part 21 Manual of Standards (CD 1706MS-1)

Closed 8 Nov 2017

Opened 11 Oct 2017

Results updated 12 Dec 2017

CASA published CD 1706MS-1—Summary of proposed transition of ATSOs and CAO 101.55 into the Part 21 MOS—on the CASA website from 11 October to 8 November 2017 and invited industry and the public to comment on the proposals outlined.

The purpose of the consultation was to discuss the proposed transition of particular Australian Technical Standard Orders (ATSOs) into the Part 21 Manual of Standards (MOS) and the proposed repeal of other ATSOs and historical standards.

CASA received two online submissions. Only one respondent consented to publishing their response on the CASA website.

Key feedback and policy changes

Repeal of ATSOs

Both respondents supported the repeal of the ATSOs proposed by CASA. One respondent queried the need for the existence of ATSOs under any circumstances.

CASA maintains that ATSOs provide an important mechanism for the regulatory approval of equipment, particularly where an ATSO is developed on the basis of a request from industry, as has occurred more recently.

Transfer of ATSOs into Part 21 MOS

One respondent supported the proposed transition of particular ATSOs into the Part 21 MOS. The other respondent did not support the proposed transition of ATSOs. The objections raised by this respondent related to a perceived lack of need for ATSOs altogether, rather than specific objections relating to the ATSOs proposed to be transitioned.

CASA has outlined that the ATSOs proposed to be transitioned are those for which current ATSO authorisations (ATSOAs) have been issued.

Repeal of CAO 101.55

Both respondents supported the repeal of CAO 101.55.

Next steps

CASA intends to proceed with the repeal and transition of ATSOs as outlined during the consultation process.

CASA also intends to proceed with the repeal of CAO 101.55 as outlined during the consultation process.

CASA thanks respondents for their participation and feedback on these proposals.


Published responses

View submitted responses where consent has been given to publish the response.


The third-tier legislation that relates to Part 21 of the Civil Aviation Safety Regulations 1998 (CASR) is currently spread across a range of legislative and non-legislative instruments such as the Civil Aviation Orders (CAOs) and the Australian Technical Standard Orders (ATSOs). CASA intends to consolidate the content of these instruments into the Part 21 Manual of Standards (MOS) in order to provide a single source for third-tier legislation, thereby reducing the overall complexity of the legislation and any subsequent administrative burden for industry.

Due to complexities involved with legal drafting, the transfer of the contents of the CAOs and ATSOs to the Part 21 MOS could not be completed before the MOS came into effect on 1 June 2016. Instead, the standards in CAO 101.55 and the ATSOs were incorporated into the Part 21 MOS by reference, and a deadline of 30 November 2017 set to completely transition their content into the Part 21 MOS.


Why your views matter

CASA recognises the valuable contribution that community and industry consultation makes to the regulatory development process. This consultation draft sets out the proposed transition of ATSOs and CAO 101.55 into the Part 21 MOS.

A copy of the briefing paper is provided below. You can read it on this screen using the scroll bar or save it to your computer using the popup options. Annexes are provided in the 'related' section further down this page.

Please read the documents before providing your feedback in the online survey.

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What happens next

At the end of the response period for public comment, we will review each comment and submission received through the online response form. We will make all submissions publicly available on the CASA website unless a respondent requests that their submission remain confidential. Information about how we consult and how to make a confidential submission is available on the CASA website.

When the consultation draft submissions are published we will also publish a summary of consultation, which will summarise the feedback received, describe any intended changes and detail our plans to make the rule changes.

If we do change the rules, information about the rule making will be available in the Explanatory Statement that is published with the final rule on the Federal Register of Legislation. You can subscribe to our consultation and rule making mailing list to be notified of future consultation or rule making.



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