Obstacles (Wind Farms) outside the vicinity of a CASA certified aerodrome - draft advisory circular 139.E-05 v1.0

Closed 10 Feb 2021

Opened 13 Jan 2021


This is the second version of an advisory Circular (AC) which relates to obstacles (wind farms) outside the vicinity of a Civil Aviation Safety Authority (CASA) Part 139 of the Civil Aviation Safety Regulations aerodrome. AC 139.E-05 v1.0, replaces AC 139-18 v0 - obstacle marking and lighting of wind farms, which was withdrawn from circulation in 2009.

The purpose of AC 139.E-05 v1.0, is to provide guidance and advice about the CASA assessment of wind farm related aviation hazards in relation to:

  • obstacles outside the vicinity of a Part 139 Aerodrome
  • wind farm hazard lighting
  • CASA’s assessment of windfarm related aviation hazards or obstacles.

This guidance would be of use to:

  • persons involved in the design, construction and operation of wind farms and wind monitoring masts
  • proponents of wind farms and wind monitoring masts
  • planning authorities
  • aerodrome and aircraft landing area operators
  • the Civil Aviation Safety Authority.

The revision of this AC is not a result of the newly made Part 139 which came into effect in August 2020.

Why we are consulting

We are seeking feedback on whether the AC provides adequate guidance on the CASA’s assessment of wind farm related aviation hazards and obstacles, and if is fit for purpose.

A copy of the draft AC is provided below and within the consultation. Please read the AC before providing your feedback in the online survey.

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 you request your submission remain confidential. We will also publish a Summary of Consultation which summarises the feedback received, outlines any intended changes and details our plans for the AC.

To be notified of any future consultations, you can subscribe to our consultation and rulemaking mailing list


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