SART, EPirb, plb & mob beacons

EPIRBS (Emergency Position Indicating Radio Beacon)

Knowledge of:

• EPIRB features including antenna, battery (and expiry date), HEX ID, activation system, mounting system and flashing light
• 406MHz Cospas-Sarsat system
• Testing, service and maintenance recommendations for EPIRBs
• EPIRBs may also incorporate a 121.5MHz homing signal, a GNSS receiver or AIS transmitter
• Each device will have a battery expiry date

Understands:

• Requirement to register a 406MHz beacon and how this is done in the UK 
• When and how to activate an EPIRB
• The action to take in the event of an inadvertent EPIRB activation
• The differences between an EPIRB and PLB

SART (Search And Rescue Transponder)

Knowledge of:

• Various AIS and DSC MOB beacons are commercially available but not part of GMDSS

Understands:

• The differences between AIS- and Radar-SARTs
• How an AIS-SART will appear on a display and how it is used for SAR
• How an activated RADAR-SART will appear on a display and how it is used for SAR
• Each device will have a battery expiry date

Can:

• Calculate approximate ranges between a SART and other stations

HANDHELD VHF

Understands:

• Differences between the operation of handheld and fixed VHF sets
• Importance of having a spare battery or suitable charging routine to ensure the handheld VHF has power when needed

Can:

• Calculate approximate ranges between a handheld VHF and other stations 

EPIRB (Emergency Position Indicating Radio Beacons) and PLB (Personal Locator Beacons) are a fast effective way of distress alerting for any kind of vessel. 

A 406MHz beacon enables the SAR (Search and Rescue) agencies to quickly and accurately identify and locate a casualty so that they can effect a successful rescue.

How do they work? 

The frequencies in the band 406.0 - 406.1 MHz are reserved for the exclusive use of distress beacons operating with satellite systems and it is on this 406 MHz frequency a distress radio beacons transmits if activated. 

• the signal it transmits is detected by instruments on board satellites in the COSPAS-SARSAT International Satellite System for Search and Rescue. 
• Local Users Terminals which are the ground receiving stations receive and process the satellite downlink signal, thereby generating distress alerts. 
• the distress alerts are passed to a Mission Control Centre which 
• relays them to the search and rescue point of contact. For a UK registered beacon this would be the National Maritime Rescue Co-ordination Centre (NMOC) at Fareham. 

The signal transmitted by the distress radio beacon includes a digital message which allows the transmission of encoded data such as the unique identifier for the beacon that transmitted the alert and if the beacon has an integral GPS, the beacon’s position.  Otherwise the beacon’s signal may need to be detected by two or three satellites before its position can be sufficiently estimated, therefore it may take longer for SAR to be initiated. 

The unique identifier links the beacon to the data held by the UK 406 MHz Beacon Registry about the vessel or person. This database is available 24/7 and gives the Rescue Co-ordination Centre critical information, such as what type of vessel is in distress.   They need to know whether they are dealing with a cruise ship carrying thousands of people, a container ship or tanker, a fishing boat or a yacht, to know what response is needed.

Text © www.rya.org.uk 

Understands:

• the action to take in the event of an inadvertent EPIRB activation

Understands:

• The differences between an EPIRB and PLB

PLBs operate in the same way as an EPIRB in that they are 406MHz, satellite-based devices that use the Cospas-Sarsat system.  PLBs are designed primarily to be worn on the person and typically have a shorter battery life than an EPIRB. The device may or may not be fitted with a GNSS receiver. Some may also omit a 121.5MHz homing signal. Testing and transportation should be done according to each manufacturer’s instructions. These devices are suited to seafarers who operate in remote locations where assistance may not be in the immediate vicinity.

PLBs must be registered with the national 406MHz-beacon registry which, in the UK, is the MCA Beacon Registry https://www.gov.uk/maritime-safety-weather-and-navigation , and listed on a Ship Radio Licence or a Ship Portable Radio Licence.

PABs are AIS-based devices which have more of a homing purpose as they are limited to VHF range which, for a short antenna on a person at sea level, may be no more than five miles. Older AIS receivers may see a PAB signal as a vessel not as a circle with a cross inside as is recommended by the IMO. The device is fitted with a GNSS receiver. Testing and transportation should be done according to each manufacturer’s instructions. These devices are ideal for seafarers who would expect assistance from another crew member, nearby vessels or stations. PABs must be listed on a Ship Radio Licence or a Ship Portable Radio Licence.

Some personal MOB devices incorporate DSC functionality so that a DSC transmission can be issued by the MOB. The specification for these units varies between manufacturers and by country and the technology is constantly evolving for the leisure-use market. These beacons must be listed on a Ship Radio Licence or a Ship Portable Radio Licence.

• Understands the differences between an AIS- and Radar-SARTs
• Understands how an AIS-SART will appear on a display and how it is used for SAR
• Understands how a Radar-SART will appear on a display and how it is used for SAR

A Search and Rescue Transponder (SART) is an electronic device that automatically reacts to the emission of a radar. This enhances the visibility on a radar screen. SART transponders are used to ease the search of a vessel in distress or a liferaft.

A SART has a receiver that detects the signals from X-band radars (9.2 - 9.5 GHz). If the SART detects a signal it immediately transmits twelve pulses on the same frequency. This signal is seen by the radar as "echoes" and will be displayed on the screen as a series of twelve dots with a gap of 0.6 miles between them. The first dot is at the position of the SART and the others go in a straight line towards the edge of the screen.

If the rescue vessel approaches the SART, the twelve dots will become short arcs. These arcs increase in size if the vessel gets closer. If the rescue vessel is very close, the SART will be activated permanently by the side lobes of the radar antenna. The signal of the SART will then be visible as twelve complete circles on the radar screen. This will tell the search-and-rescue team that they have more or less arrived.

• Understands how a Radar-SART will appear on a display and how it is used for SAR

• Understands how an AIS-SART will appear on a display and how it is used for SAR

• as a circle with a cross inside it and a text message stating "SART ACTIVE"

Understands:

• The differences between AIS- and Radar-SARTs