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COSPAS-SARSAT system coverage for 121.5/243 MHz EPIRBs using local user terminals
located in Queensland, Western Australia and New Zealand. Median time to detect and
locate an activated beacon is also shown. (The lighter shading indicates Australia's area
of responsibility for search and rescue.)
111.6 It can be seen from the diagram that the 121.5/243 MHz EPIRB can provide
significant support to search and rescue operations in all Australian and New
Zealand coastal waters. Parts of the Indian, Southern and Pacific Oceans, the
Timor Sea and waters around Papua New Guinea also fall into the service
area of the three LUTs.
111.7 Although LUTs established in other countries provide a service for 121.5/243
MHz EPIRBs in other areas, major parts of the Indian, South Atlantic and
Pacific Oceans remain uncovered.
111.8 Vessels making voyages outside 121.5/243 MHz service areas should carry a
406 MHz EPIRB. It is recommended that vessels proceeding more than 30
nautical miles offshore carry a 406 MHz EPIRB.
112. Satellite Detection and Location of Older 121.5/243 EPIRBs
112.1 Because of the sophisticated technology used in the COSPAS-SARSAT
satellite detection and location system, the ACA (and its predecessors) has
enforced stringent technical standards for 121.5/243 MHz EPIRBs
manufactured and sold after March 1990.
112.2 All EPIRBs manufactured to this standard, which the Radiocommunications
Standard (121.5 MHz and 243.0 MHz Emergency Position Indicating Radio
Beacons) No.1 of 1996, are capable of being detected and located by
satellites in the manner described in paragraphs 111.1 - 111.4. This standard
may also be known as Australian/New Zealand standard AS/NZS 4330:1995,
and was previously known as Ministerial Standard 241 (MS241).
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112.3 Tests carried out by search and rescue authorities on earlier models of
121.5/243 MHz EPIRBs, which are likely to bear a label certifying compliance
with specification DOC 241A or 241B, show that very few of them are likely to
be detected by the satellite system. Of those beacons which were detected,
the calculated positions were inaccurate and misleading.
112.4 The Australian Maritime Safety Authority (AMSA) has stated that an owner of a
121.5/243 MHz EPIRB manufactured prior to 1990 should assume that this
beacon is incompatible with the satellite system. The Authority strongly
recommends that boat owners replace older EPIRBs with a type that meets
AS/NZS 4330:1995, or the earlier MS 241 standard.
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Section 20 406 MHz EPIRBs
113. Methods of Detection and Location
113.1 The 406 MHz EPIRB radiates signals on the frequency of 406.025 MHz.
Those 406 MHz EPIRBs manufactured to Australian specifications will
additionally radiate signals on 121.5 MHz for aircraft homing purposes.
Australian 406 MHz EPIRBs can be detected and located by two methods:
" by aircraft within range listening on the civil aeronautical distress
frequency of 121.5 MHz; and
" by the COSPAS-SARSAT satellite system.
114. Detection and Location by Aircraft
114.1 The method of detection and location of the 121.5 MHz signal component of a
406 MHz EPIRB by aircraft is similar to that described in paragraphs 110.1 -
110.3 for 121.5/243 MHz EPIRBs.
115. Detection and Location by Satellite
115.1 Signals radiating from an activated 406 MHz EPIRB will be detected by
satellites of the COSPAS-SARSAT system and relayed back towards the
Earth. These signals are similar to those from a 121.5/243 EPIRB, and in a
like manner, will be received by any LUT in the satellite's view.
115.2 Because signals from a 406 MHz EPIRB are in a digitised form, they can also
be stored in the satellite's memory. As the satellite's path brings it into view of
a LUT, information, including time of first detection, is retrieved from the
satellite's memory and relayed down to the LUT. This information is processed
and passed to a rescue coordination centre, providing both an alert and a
position.
115.3 A 406 MHz EPIRB can generally be located by the satellite system to a radius
of better than 5 km (2.7 nautical miles). Final location of the distress scene
can be carried out by aircraft "homing" on the 121.5 MHz component of the
EPIRB signal.
115.4 Because of the satellite's ability to memorise signals from a 406 MHz EPIRB,
detection and location of this type of beacon does not suffer the geographical
limitations of the 121.5/243 MHz model. An activated 406 MHz EPIRB can be
detected and located at any place on the Earth's surface.
115.5 It is strongly recommended that all vessels making a voyage from Australia to
any destination outside the limits of 121.5/243 MHz beacon coverage carry a
406 MHz EPIRB.
115.6 406 MHz EPIRBs have numerous advantages over the 121.5/243 MHz types.
These advantages include:
" the ability to be located more accurately;
" identification of the owner/operator enables search and rescue
authorities to obtain more intelligence before initiating a response;
" future generation beacons will have the capability of detection by
geostationary satellites enabling near instantaneous detection; and
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" future generation beacons will have the capability of transmitting
position data memorised from an interface with satellite navigation
receivers (GPS).
116. Identification of 406 MHz EPIRBs
116.1 Every 406 MHz EPIRB has a unique identity code which is transmitted as part
of its signal and which also indicates the country of registration. This code is
programmed into the beacon by the supplier before it is offered for purchase.
116.2 As a result, local user terminals anywhere in the world receiving a distress
alert and location from an activated 406 MHz EPIRB, can also identify the
vessel in distress and the beacon's country of registration.
116.3 If this system is to work successfully, and for their own safety, it is essential
that purchasers of 406 MHz EPIRBs complete the registration form provided
by the supplier and mail it to RCC Australia in Canberra. The completion of
this registration process will ensure that the RCC is equipped with information
vital to a successful rescue mission.
116.4 It is just as important that purchasers of second-hand 406 MHz EPIRBs, also
provide their details to the RCC.
117. Activation of 406 MHz EPIRBs
117.1 406 MHz beacons are available in two types:
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