Commercial and Business Aviation Advisory Circulars

INTRODUCTION

This Commercial and Business Aviation Advisory Circular (CBAAC) is intended to make air operators aware that they should operate in accordance with an approved Aircraft Flight Manual (AFM) Supplement, or other approved data, that ensures safe operations of transport category aeroplanes on narrow runways.

APPLICABILITY

All air operators operating under Subparts 704 and 705 of the Canadian Aviation Regulations.

REFERENCES

Aircraft Certification Advisory Circular No. 525-014, Issue No. 01, Certification of Transport Category Aeroplanes On Narrow Runways.  http://tcinfo/CivilAviation/certification/guidance/525/525-014.htm

BACKGROUND

International Civil Aviation Organization (ICAO) Annex 14, Volume 1, Aerodrome Design and Operations, Chapter 1.3 defines an aerodrome reference code depending on aeroplane performance and physical dimensions (wing span and distance between outside edges of the main gear wheels). For example, for the DHC‑8‑100/200/300 series of aeroplanes using the ICAO document, the recommended minimum width is 30m (98 feet).

Transport Canada publication TP 312, Aerodrome Standards and Recommended Practices, contains the same methodology as the ICAO document resulting in the same recommended minimum width for the DHC‑8‑100/200/300 series of aeroplanes.

Federal Aviation Administration Advisory Circular 150/5300-13, Change 5 dated 14 February 1997, Airport Design Standards - Transport Airports, Chapter 3, paragraph 302 relates the runway width to an Airplane Design Group classification (which depends on wingspan), maximum take-off weight, and approach category (which depends on approach speed).

The above are aerodrome design standards relating the required width of the runway to the type of aeroplane the runway is intended to serve. It is assumed that the aeroplane performance and handling requirements contained in the basic airworthiness code are appropriate to the specified minimum width. For runways whose minimum width is narrower than those determined using ICAO Annex 14, Volume 1, Chapter 1.3 Reference Code, the existing requirements are inadequate. For such occurrences, Transport Canada, Aircraft Certification develops a Special Condition – Airworthiness that becomes part of the basis of certification in the aeroplane's type certificate.

POLICY DEVELOPMENT

The minimum runway width is that which is sufficient to allow the aeroplane to be safely controlled during take-off and landing using procedures, which can be consistently executed in service by crews of average skill. The width shall be sufficient to prevent any landing gear wheel from leaving the runway during take-off and landing in expected operating conditions, including engine failure.

ACTION

Air operators need to be aware that their aeroplanes may not be meeting the criteria for their type certification, unless they operate in accordance with the appropriate approved data.

Air operators who plan to operate on an airport with runways less than 150 feet wide, should check whether the manufacturer has published procedures for doing so in an AFM Supplement.

For example, in the case of the DHC‑8‑100/200/300 series there is an AFM Supplement that contains approved data for operation from dry, hard surface, narrow runways as defined above.  Air operators operating on narrow runways must do so in compliance with the limitations stipulated in any supplement published in the AFM for the aeroplanes they are operating.

If no AFM approved data exists, air operators should contact the particular aircraft manufacturer and request that the manufacturer seeks Transport Canada, Aircraft Certification approval for the desired minimum runway width.

Canadian AFMs pertaining to the operation of aircraft from narrow runways contain the following statement: “This supplement does not constitute approval to conduct operations from narrow runways”.  In order to be compliant with the above statement, it is recommended that air operators detail in their Company Operations Manual their procedures for operating into and out of an airport with  narrow runways.

FUTURE DISPOSITION

This CBAAC will remain in effect until further notice.

CONCLUSION

This CBAAC brings to the attention of air operators the requirement that they must operate in accordance with an approved AFM Supplement, or other approved data, to ensure safe operations of transport category aeroplanes on narrow runways.

Michel Gaudreau
Director
Commercial and Business Aviation