Quiz 07: Emergency Beacons (EPIRBs & SARTs)

1. Which primary radio frequency is used by modern Emergency Position Indicating Radio Beacons (EPIRBs) to transmit digital distress alerts to international satellite networks?

156.800 MHz 121.500 MHz 406.000 MHz 2182.000 kHz

Correct Answer: C. Modern EPIRBs transmit their core digital distress signals on the 406 MHz frequency, which is monitored globally by the COSPAS-SARSAT satellite system.

2. What is the operational purpose of the secondary 121.5 MHz low-power signal emitted by a standard 406 MHz maritime EPIRB?

To upload continuous high-speed digital text logs to weather monitors. To serve as a short-range homing signal that rescue aircraft and vessels can track visually or with direction finders. To broadcast automated voice distress messages on VHF Channel 16. To communicate with local commercial cell phone towers.

Correct Answer: B. The 121.5 MHz frequency is used as a short-range homing signal, helping rescue crews locate survivors during the final stages of a search.

3. How does the integration of an internal GPS/GNSS receiver affect the performance of a 406 MHz EPIRB?

It doubles the battery life of the beacon. It improves location accuracy from about 5 kilometers down to approximately 100 meters, and speeds up detection time to just a few minutes. It allows the beacon to receive voice replies from the rescue center. It eliminates the need to register the beacon with national maritime authorities.

Correct Answer: B. Built-in GPS/GNSS routing immediately includes coordinates in the satellite message, reducing search fields to around 100 meters and eliminating the need to wait for multiple satellite passes.

4. What type of physical mounting device allows a float-free category EPIRB to deploy automatically from a sinking vessel?

A heavy-duty steel lock pad unit A Hydrostatic Release Unit (HRU) that unlocks automatically when submerged to a depth of 1.5 to 4 meters. A magnetic proximity sensor switch linked to the main battery room. A manual break-glass plastic shield assembly.

Correct Answer: B. An HRU uses water pressure at depths between 1.5 and 4 meters to cut its retaining bolt, allowing the spring-loaded bracket to release the beacon so it can float to the surface.

5. Under what condition will a standard marine EPIRB automatically begin transmitting distress signals if it is removed from its storage bracket?

As soon as it is exposed to direct ambient sunlight. When it comes into contact with water, activating its built-in sea switch terminals. When the temperature of its outer casing drops below freezing. Only when it is turned upside down three times in a row.

Correct Answer: B. Most marine EPIRBs have metal sea-switch terminals on the casing. When wet, these terminals complete an electrical circuit that activates the beacon automatically if it has floated free.

6. Why is it mandatory for vessel owners to register their 406 MHz EPIRBs with national authorities like AMSA in Australia?

To activate the internal GPS hardware chip over commercial channels. To link the beacon's unique HEX ID code to contact info, vessel description, and emergency points of contact, helping authorities quickly identify false alerts. To pay annual regulatory radio frequency licensing fees. To download mandatory operating software updates.

Correct Answer: B. Registration links the beacon's unique hex code to details about the boat and its owner, allowing search and rescue teams to verify alerts and gather information before deploying resources.

7. How long must an approved 406 MHz maritime EPIRB battery be capable of continuously transmitting once it is activated in an emergency?

At least 12 hours At least 24 hours At least 48 hours At least 72 hours

Correct Answer: C. International safety regulations require maritime EPIRB batteries to power continuous signal transmissions for at least 48 hours, even in freezing conditions.

8. What action must be taken immediately if an EPIRB is accidentally activated on board a vessel?

Turn off the unit immediately and contact rescue coordination centers (like AMSA) to report the accident and cancel the false alarm. Throw the beacon overboard to prevent radio interference on the bridge. Hide the beacon in a metal storage box to block the signal without turning it off. Keep it on until the battery drains completely to verify it works.

Correct Answer: A. False alerts must be switched off and reported to search authorities immediately to stand down satellite tracking and prevent wasting rescue resources.

9. What does the acronym 'SART' stand for within the Global Maritime Distress and Safety System (GMDSS) framework?

Satellite Automated Radio Terminal Search and Rescue Transponder Shipboard Automated Tracking System Synchronized Array Radar Tracker

Correct Answer: B. SART stands for Search and Rescue Transponder. It is a portable survival craft device used to pinpoint location during search operations.

10. Which radar frequency band do standard marine Radar SART units interact with to display emergency patterns on search vessels' radar screens?

3 GHz (S-Band) marine radar network 9 GHz (X-Band) marine radar network 400 MHz satellite radar array 24 GHz commercial millimeter bands

Correct Answer: B. Standard radar SARTs operate in the 9 GHz band, meaning they only interact with and show up on X-band marine radars.

11. How does an active Radar SART display its location on an intercepting vessel's X-band radar screen when the search ship is still several miles away?

It shows up as a single blinking red cross symbol. It creates a line of 12 evenly spaced dots extending outward from the SART's location along its radar bearing line. It blanks out the radar screen completely to draw attention. It draws a solid circle around the search vessel's position marker.

Correct Answer: B. An active SART responds to radar sweeps by generating a distinctive line of 12 dots on the search radar screen, clearly marking its bearing line.

12. What change happens to the 12-dot SART pattern on a rescue vessel's radar screen as the ship approaches very close to the survival craft?

The dots vanish completely, leaving only a blank screen space. The 12 dots widen into solid concentric arcs, turning into complete circles when the rescue ship arrives at the location. The dots turn into a flashing square icon around the target tracker. The pattern flips upside down on the display monitor.

Correct Answer: B. As the rescue vessel gets closer, its radar signals trigger the SART continuously, causing the dots to widen into arcs and eventually form full concentric circles when the ship is on scene.

13. Where should a SART be mounted inside a survival liferaft to maximize its line-of-sight range across the water?

Placed on the floor underneath the raft's equipment bags. Mounted as high as possible inside the liferaft, using the provided extension pole or internal canopy pocket. Dropped into the water to float alongside the raft on a short lanyard tether. Tied underneath the bottom of the raft's hull structure.

Correct Answer: B. Height is critical for line-of-sight radar signals. Mounting the SART at least 1 meter above the water significantly extends its detection range for search vessels.

14. What alternative technology is used in newer modern life-saving transponders instead of traditional 9 GHz radar signals to broadcast locations to nearby shipping?

Shortwave AM radio transmitters AIS-SARTs, which use Automatic Identification System channels to transmit GPS positions directly to nearby charts. Infrared laser light beams Commercial satellite video streaming links

Correct Answer: B. AIS-SARTs use standard AIS VHF frequencies to broadcast precise GPS coordinates. This position shows up directly as a distress target icon on modern electronic charts (ECDIS/chartplotters).

15. How can survivors inside a liferaft tell if a rescue ship or search aircraft is close enough that its radar is actively sweeping their SART?

The SART will play a pre-recorded voice message aloud. Built-in indicator lights or internal audio buzzers on the SART will flash or sound to notify the occupants. The device will heat up significantly to the touch. The battery unit will pop out of its base compartment slot.

Correct Answer: B. SARTs include visual indicators (LEDs) or audio alarms (buzzers) that change behavior when painted by a radar sweep, letting survivors know a rescue craft is nearby.