5.2 EPIRBs & Emergency Beacons

5.2 Survival Craft Radios, SARTs & EPIRBs

Quick Answer: In the liferaft or lifeboat you need three complementary tools. Portable survival-craft VHF gives Channel 16 voice to ships and rescue units nearby. A SART answers 9 GHz X-band radar with a line of about 12 dots so rescuers can home on radar. An EPIRB is a float-free, battery-powered beacon that alerts COSPAS-SARSAT (primarily 406 MHz) so shore SAR authorities know you need help. Test carefully, replace batteries on schedule, and never leave a false EPIRB alert uncancelled.

Element 1 Subelement D groups these devices because they are “other equipment” beyond the bridge VHF/MF console—yet they are often what still works after the ship is gone.

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Portable Survival-Craft VHF Radiotelephones

Role: two-way voice among survival craft, between survival craft and the mother ship, and between survival craft and rescue units. The pool treats that full set as all of the above.

Capabilities the exam expects

Statements that are NOT true (classic “which is NOT true” stems)

• Operates simplex on Channel 70 and at least one other channel — NOT true as a survival-craft voice radio requirement (Ch-70 is DSC, not survival-craft voice traffic).
• Operation on Channel 13 — NOT a required survival-craft portable VHF capability (Ch-13 is bridge-to-bridge navigation on the ship).

Memory split:

• Ship bridge → Ch-13 navigational watch, Ch-16 distress/safety/calling, Ch-70 DSC
• Survival craft handheld → Ch-16 voice first; watertight; fixed antenna; simple power-on use

Carriage concepts (high-level GMDSS / Element 1)

Compulsory GMDSS-oriented ships carry multiple portable two-way VHF sets so they can be placed rapidly into survival craft:

Stow them so they can be grabbed and carried into survival craft—not locked in a radio room that floods first.

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SART — Search and Rescue Transponder (Radar Beacon)

What a SART is

A SART is a 9 GHz radar transponder designed to be received on a vessel’s X-band navigational radar (about 9.2–9.5 GHz). It is not:

• A 406 MHz satellite beacon (that is the EPIRB)
• An S-band-only device
• A DSC controller
• A performance monitor permanently wired into the ship’s radar

Activation logic (easy to mix up with EPIRB)

1. Survivors switch the SART ON.
2. It does not need to “broadcast forever into empty ocean” like a free-running voice MAYDAY.
3. When a searching ship’s X-band radar illuminates it, the SART replies.
4. On the radar PPI, rescuers see roughly twelve dots lined up on the bearing to the SART; as range closes, dots become arcs/circles (advanced display detail useful for understanding, even if Element 1 mainly wants “12 dots”).
5. The SART’s beep/alarm tells people in the raft that a radar (possible rescue) is nearby.

Range discipline

Microwave SART paths are essentially line-of-sight. Height wins:

• Hold the unit high on a pole or have a survivor raise it
• Do not count on “high power switch” myths—SARTs are not bridged VHF radios with a 1 W / 25 W toggle
• Do not mount it horizontal “to match radar polarization” as a pool-style correct answer—the tested range maximizer is height

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EPIRB — Emergency Position Indicating Radio Beacon

Definition

An EPIRB is a battery-operated emergency position-indicating radio beacon that can float free of a sinking ship, turn on (automatically for float-free Category I-style installations), and transmit a distress signal for satellite detection.

If a ship sinks, what device is designed to float free, activate, and transmit distress? → An EPIRB (emergency position indicating radio beacon).

COSPAS-SARSAT and 406 MHz

Many units also radiate a 121.5 MHz homing signal for local aircraft/ship direction-finding, but the satellite alerting story Element 1 emphasizes is the 406 MHz COSPAS-SARSAT path—not “any frequency” and not classic 2182 kHz EPIRB distractors.

Float-free vs manual concepts (operator level)

• Float-free / automatic release installations are designed so that if the ship sinks, the EPIRB leaves its bracket, reaches the surface, and activates.
• Manual activation is still critical if you abandon ship before sinking, or if the hydrostatic release fails.
• Element 1’s “float free + automatic + distress signal” stem points to the EPIRB, not the bridge-to-bridge radio and not an “auto alarm keyer on any frequency.”

Batteries and false alerts

False EPIRB cancellation is not the same procedure as cancelling a false VHF DSC alert with a Channel 16 “all stations” voice message. For EPIRB, Element 1 wants immediate RCC / Coast Guard notification.

Testing without creating a real SAR scramble

• Use the manufacturer’s self-test function (often a dedicated test position or button sequence).
• Do not deliberately activate a live distress transmission “to see if satellites hear you.”
• Log required EPIRB tests/inspections (monthly self-test language is common in marine inspection practice and related log topics).
• After any real activation, plan on battery replacement and any required servicing before the next voyage.

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How the Three Devices Fit GMDSS Sea Areas (High Level)

Element 1 is not a full GMDSS Radio Operator exam, but you should see the layers:

Sea-area intuition (Element 1 level):

• A1 (VHF DSC coast coverage): shipboard VHF-DSC is primary near shore; survival VHF still matters after abandon-ship.
• A2/A3/A4 concepts push MF/HF, satellite, and redundancy—but EPIRB + SART + portable VHF remain the abandon-ship package across sea areas.

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Decision Map for Subelement D Survival Gear

Know the three devices by frequency family, who they alert, and how you test them without lying to the SAR system—that is the heart of Element 1 Subelement D survival equipment.