Aerodrome Safety Circular (ASC) No. 2005-027

ASC 2005-027


The validity of AK documents in the current context of the Canadian Aviation Regulations (CARs).


This is to advise all aerodrome operators, airport equipment manufacturers and consulting engineers of Transport Canada, Aerodromes and Air Navigation's position regarding the legal validity of the previous Airports Group, AK series of documents.


Prior to the privatization of Transport Canada airports, the previous Airports Group of Transport Canada (AK) produced guidance documents that were used to supplement aerodrome standards for Transport Canada owned and operated airports. These guidance documents were never developed to be in contravention of existing regulations or standards and were to provide guidance material only.

Some of these AK documents, for example "Airside Guidance Signs" (K332-3E) and "Approved Airport Equipment" (T16970-E17), have implied Transport Canada approval of specific material contained within these documents.

Some airports have followed the guidance material in these AK documents and as a result have been found to be in non-conformance to specific standards contained within TP 312, 4th edition.


In its role as a regulator, Transport Canada, Civil Aviation develops and establishes aerodrome standards based upon recognized safety parameters.

Although many useful guidance materials are available in AK documents, they have not been supported nor updated by Transport Canada, Civil Aviation for many years. Some of the information contained in them is outdated and inconsistent with current regulatory requirements under CARs Part III and TP 312, 4th edition.

The content of the AK documents constitutes guidance material only, holds no legal standing and must be verified by anyone wanting to use them, against the existing Canadian Aviation Regulations and Standards.

It is to be noted that Transport Canada, Civil Aviation is not publishing nor distributing AK documents.


Airport operators found to be in non-conformance to the applicable Aerodrome Standards and Recommended Practices with regards to signs, as a result of guidance provided by AK documents will be allowed to indicate (in their corrective action plan [CAP]) that the non-conformity will be corrected when the signs are replaced.

Any and all AK documents are to be used as guidance material only and do not supersede Canadian Aviation Regulations and Standards.

For additional information on this issue, please contact:

a)  the appropriate regional Transport Canada Aerodromes and Air Navigation office (refer to the list attached), or

b)  the Aerodromes and Air Navigation Branch in Ottawa.

Aerodrome Safety Circulars issued by the Aerodromes and Air Navigation Branch are available electronically at:


Jennifer J. Taylor

Aerodromes and Air Navigation
Civil Aviation, Transport Canada