Marking and lighting of obstacles to air navigation

The Aeronautical Assessment Form (AAF) is now to be submitted using an online application.

Under visual flight rules (VFR), pilots need to see obstacles quickly and clearly. Canadian law requires some objects to be marked and lit so they can be easily seen during both day and night. The most common obstacles include:

broadcast towers
buildings
catenaries (cable crossings)
bridges
cooling towers, and
chimneys

If you’re building a new structure that will be an obstacle to air navigation or modifying an existing one (including changing its ownership), you must submit an Aeronautical Assessment Form (AAF) to Transport Canada. Guidance is provided in the advisory circular AC 601-007 When to Submit an Aeronautical Assessment Form (AAF).

Canada’s rules regarding obstacles to air navigation

You will find rules that apply to obstacles in Sections 601.23 to 601.29 of the Canadian Aviation Regulations (CARs) which include:

basic criteria for when structures are considered "obstacles"
requirement to notify Transport Canada, if you plan to install an obstacle
determination by Transport Canada of whether your structure is an obstacle
requirements for marking and lighting obstacles according to Standard 621
when you need to upgrade marking and lighting
how Transport Canada assesses proposals for equivalent marking and lighting
requirement to notify the NAV CANADA Flight Information Centre about any deterioration, failure or malfunction of marking or lighting.
forbiddance to damage obstacle marking or lighting

Standard 621 includes technical specifications on types of marking and lighting, and how these are to be applied to different kinds of obstacles.

Building or modifying an obstacle

You should also make a similar submission to NAV CANADA's Land Use Program.

If you're building or modifying a structure that will be an obstacle you will need to mark and/or light it in according to Standard 621 or as specified in the Transport Canada determination.

If you're removing [demolishing] an obstacle, the Transport Canada regional office and NAV CANADA's Land Use Program are notified.

If your structure will be on, over, under, through or across any navigable water you may also need to have your project approved by Navigation Protection Program (NPP). To find more information and to apply, go to the Navigation Protection Program (NPP).

Submit an (AAF) to Transport Canada

Online through myTC Accounts. This service is now exclusively available online.

To access and submit an AAF, you need to:

Sign in or register with GCKey which is the access point to myTC Accounts
- Click the “Apply Now” button below and log in using GCKey, a secure online credential provided by the Government of Canada. GCKey serves as the access point to your myTC Account.
- If you do not already have a GCKey, you can create one during the login process
Log in or create a myTC Account:
- Once signed in with GCKey, log in to your existing myTC Account. If you don’t have one, follow the prompts to create a new myTC Account.
- Once inside your myTC Account, you can either create a new AAF form or duplicate a previously submitted form saved in your dashboard to save time.
- Follow the prompts to complete the required information fields in the AAF.
Review and submit the form:
- Carefully review all the information entered to ensure accuracy before submitting.

After successfully submitting your form, you will receive a confirmation email for your records.

Please note that your AAF submission does not constitute authority for construction. Nor does it replace any approvals, permits or assessments by NAV CANADA, Innovation Science and Economic Development Canada, other Federal Government departments, Provincial or Municipal land use authorities or any other agency from which approval/assessment is required.

Apply Now

After you submit an AAF

Once submitted, the AAF is assigned to a Transport Canada inspector who will assess whether the object constitutes an obstacle to air navigation and, if so, will specify the required mode of protection.

If clarification is needed, the inspector will contact you directly by email. Otherwise you can expect to receive TC’s determination within 60 business days. The determination is valid for a period of 18 months from the date of assessment of the proposal as submitted.

If there is any change to the intended installation, a new submission will be required.

Service Standards

The processing time is up to 60 business days from the submission date, depending on the complexity and completeness of the request. If clarification or additional information is needed, the service standard will be suspended until all required information is provided and verified as sufficient to proceed.

Reporting a marking or lighting failure

You must report any deterioration, failure or malfunction of marking or lighting to a NAV CANADA Flight Information Centre (FIC) so that a NOTAM [notices that affect aviation safety] can be issued. Find the phone number for the nearest FIC at NAV CANADA Flight Planning and Reporting. The reporting to NAV CANADA to initiate or cancel a NOTAM must be done by the owner or person responsible for the obstacle.

You can find NAV CANADA NOTAM request forms at NOTAM Requests

Your report to NAV CANADA should include:

your name, telephone number, and email address
your company name
name of the company that owns the obstacle (if different than your company name)
obstacle site or repair ticket number
NAV CANADA Land Use # (if available)
type of structure
structure’s location (latitude and longitude)
structure’s height above ground level (AGL)
overall height above mean sea level (AMSL)
structure’s estimated return to service date

Once repairs are complete, you must notify NAV CANADA so they can cancel the NOTAM.

Issuing a NOTAM doesn't mean you don't have to do the repair. If the repair will take more than 3 months, you should provide Transport Canada with a Repair Plan, that notes when the repair will be complete.

Need Help?

For technical assistance with the AAF, email TC.DigitalAviationSupport-SoutienNumeriqueAviation.TC@tc.gc.ca.

For any other general AAF-related question, you can contact the Transport Canada Centre for the region in which the project is to be installed.

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