Goodbye, 121.5: Major Changes Are Coming to the SAR Satellite System on February1, 2009

by Nancy Lugg, Aerodrome Safety Engineer, Policy and Regulatory Services, Civil Aviation, Transport Canada

On February1, 2009, the international search and rescue (SAR) satellite system, COSPAS-SARSAT, will no longer process signals from 121.5 or 243 MHz emergency locator transmitters (ELT). Why? As of that date, the system will complete its transition to digital 406MHz-only technology, which presents a faster, more capable, and more reliable form of distress alerting. The switch to 406MHz emergency beacons has been made across Canada and around the world by marine and land-based users.

With these changes, after February1, 2009, the 121.5MHz ELT from a downed aircraft will not be detected by the satellite system. Alerting of the SAR system could be significantly delayed, adversely affecting the survival of pilots and passengers and causing anguish to friends and families. Since the Government of Canada has an obligation to search for missing aircraft, delayed notification and the possibility of extended visual search missions also strains resources and increases the exposure to risk for SAR personnel, including the Canadian Forces and the volunteers of the Civil Air Search and Rescue Association (CASARA). While equipping aircraft with 406MHz ELTs ensures uninterrupted access to the COSPAS-SARSAT system, concerns have been expressed by aircraft owners about the high cost to buy and install this equipment.

The International Civil Aviation Organization (ICAO) Convention on International Civil Aviation, to which Canada is a signatory, currently requires that aircraft engaged in international operations carry at least one automatic ELT that operates simultaneously on both 406MHz and 121.5MHz. Since Canada has an obligation to adopt these standards, Transport Canada's Civil Aviation Directorate convened an Issue Analysis and Risk Assessment Team on February5, 2007, to determine how the Canadian Aviation Regulations (CARs) can best accommodate these changes, while being responsive to the concerns of the aviation community. This included evaluating alternative technologies for ensuring the prompt notification and location of downed aircraft.

Twenty-eight highly qualified participants from industry and government, having a wide range of technical and operational expertise, met over eighteen formally scheduled meetings between February and June2007. The Team consisted of representatives from the Canadian Forces, the National Search and Rescue Secretariat (NSS), Transport Canada, the Canadian Owners and Pilots Association (COPA), the Air Line Pilots Association (ALPA), the Air Transport Association of Canada (ATAC), and the Air Canada Pilots Association (ACPA).

Based on the results of their work, Transport Canada has drafted a performance-based regulation to include 406MHz ELTs as well as acceptable alternative systems. The ultimate objective is to ensure that after February1, 2009, SAR authorities can continue to be promptly notified of the occurrence and location of an aircraft accident. The proposed changes to the CARs were presented in Ottawa on November20, 2007, at a special meeting of the Canadian Aviation Regulation Advisory Council (CARAC) Part VI Technical Committee-General Operating and Flight Rules. The regulatory proposal is currently being prepared for submission to the Department of Justice for subsequent publication in the Canada Gazette.

Updates on the regulatory process will be covered in future issues of the Aviation Safety Letter (ASL), and are available on the CARAC Web site at: For more information on the COSPAS-SARSAT system and the switch to 406MHz, visit and the NSS Web site at:


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