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About Adobe Acrobat PDF Documents
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Somewhere in the forbidding Rocky Mountains of British Columbia a small airplane was reported overdue. After a thorough search failed to locate the airplane, active searching ceased. Later, three people set off on a voluntary search mission in another airplane. |
Meanwhile, silently orbiting the earth, the Soviets' COSMOS satellite picked up distress signals from an emergency radio beacon in the Rocky Mountains. Instantly, the satellite relayed the signal to a ground station in Ottawa. The ground station estimated the beacon's position and search aircraft were dispatched to the area where they, too, picked up the call for help and were soon at the site of the accident. Rescue teams quickly brought out the three people in the second airplane. They would not have survived without help; one was already near death.
Three lives had been saved - thanks to an emergency radio beacon on board an airplane, and thanks to an international satellite system called Cospas-Sarsat. The first airplane had not carried an emergency radio beacon on board ... it was never found.
Cospas-Sarsat are satellite systems that work as one. SARSAT - operated by Canada, France and the United States - stands for Search And Rescue Satellite-Aided Tracking. COSPAS, operated by Russia, performs the equivalent function.
Cospas-Sarsat satellites orbit the Earth. They are able to receive signals from emergency radio beacons and relay them to ground stations, which, in turn, process the signals to determine where the beacon is located. The ground stations then relay this information to search and rescue authorities.
The system has four parts: emergency radio beacons, which call for help; satellites, which are like ears in space; ground stations, which get the message; and control centres, which sound the alarm.
If you are in distress in a remote area, you can benefit from an emergency radiobeacon. It will not only allow your call for help to be heard, but will also provide information on where you are.
There are three kinds of radio beacons, classified by who uses them. If you are in the air, the aircraft should carry an Emergency Locator Transmitter (ELT). At sea, the vessel should have an Emergency Position Indicating Radio Beacon (EPIRB). Personal Locator Beacons (PLBs) are for land activities such as hiking or camping in the wilderness.
The radio beacons can transmit signals on certain emergency frequencies. All three types of beacons can be activated manually. As well, ELTs can be activated automatically by gravitational forces, such as those encountered in an aircraft crash,while EPIRBs can be activated by contact with water.
The first generation of beacons, mostly ELTs, transmit on 121.5 MHz. Their signals can be received by aircraft and by Cospas-Sarsat satellites. The beacons can be located by a suitable homer and by Cospas-Sarsat satellites.
The second generation of radio beacons, developed to be more readily detected by satellites, transmit on 406 MHz. Codes transmitted by these beacons can include identification of the beacon, vehicle and its country of registration. The origin of the signal can be located within a radius of two kilometres worldwide. All these features make it much easier for search and rescue forces to respond to your distress signal and to react quickly.
Beacon information is held in an Emergency Beacon Registry maintained by the National Search and Rescue Secretariat for use by rescue coordination centres.
Cospas-Sarsat satellites act like ears in space, always listening for distress calls from Earth. It's their job to receive signals from emergency radio beacons and return them to Earth so help can be sent. That's why it is so important for beacons to be carried on an airplane, on a ship, or on land in an isolated area. That way, the system can do its job if you get into trouble.
Cospas-Sarsat satellites circle the Earth in polar orbit about every 100 minutes, thus ensuring that signals can be received frequently. In Canada, because of thecongruance of satellites at the North Pole, signals are likely to be heard within an hour.
In a distress situation, the emergency radio beacon has been activated and a signal has been received by a Cospas-Sarsat satellite and returned to Earth. Now it is time for a ground station to get the message. When ground stations are in view of the satellite, they can pick up returned signals, process them, and determine the beacon's position.
A distress signal transmitted on 121.5 MHz is lost if, on receiving it, the satellite is not within range of a ground station. If no ground station is in range when a signal istransmitted on 406 MHz, the satellite will store the signal until it can return the signal to a ground station. This provides a means for distress calls to be heard regardless of their location in the world.
Operational ground stations are set up around the world. Canada has three: in Edmonton, Alberta, in Churchill, Manitoba, and in Goose Bay, Labrador.
Once the whereabouts of the radio beacon has been determined, the information is automatically forwarded to a control centre. The control centre sounds the alarm, alerting search and rescue authorities.
In Canada, the control centre is at Canadian Forces Base Trenton, in Ontario, whichalerts the search and rescue centre nearest the incident.
The role of Cospas-Sarsat ends here and search and rescue forces take over.
Canada, as well as several other countries, first became interested in using satellites to aid in search and rescue during the 1970s. In 1979, a memorandum of understanding was signed between Canada, France, the United States and the Union of Soviet Socialist Republics, creating Cospas-Sarsat. The first satellites for COSPAS and SARSAT were launched in 1982 and 1983 respectively, followed later by additional satellites.
This co-operation culminated on July 1, 1988, when the four countries signed theInternational Cospas-Sarsat Program Agreement in Paris.
Following the Agreement, the International Maritime Organization adopted the Cospas-Sarsat 406 MHz system for its Global Maritime Distress and Safety System.
Many other countries also take part in the Cospas-Sarsat Programme. These include Australia, Brazil, Chile, China, Denmark, Germany, Greece, India, Indonesia, Italy, Japan, New Zealand, Norway, Pakistan, Singapore, Spain, Sweden, Switzerland, and the United Kingdom.
Cospas-Sarsat is an outstanding example of how nations can work together toshare in the peaceful use of space and space technology.
Canadians can be proud of their involvement in Cospas-Sarsat, and are fortunate to have benefited from it. Our early interest paved the way for the development of a humanitarian, non-discriminatory system open to all nations. The system has saved many lives in Canada alone - lives of men, women, and children, isolated and in trouble - lives that might have been lost without Cospas-Sarsat.
National Search and Rescue Secretariat
275 Slater Street, 4th Floor
Ottawa, Ontario
K1A 0K2
1-800-SAR-9414 or by e-mail
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