Navigation and Seamanship

6.8.1.1. EPIRB

Four synchronous satellites orbiting around the earth at a low attitude of 850 km. Each satellite take 100 minutes to complete one polar orbit journey around the earth. Thus the satellite will available in the vicinity of the beacon, every hour . EPIRB operates at a frequency of 121.5m.Hz or 243 MHz and sends alert signal for 48 hours. The signals are picked up by rescue aircraft or by satellite. When a satellite receives a distress signal from an older EPIRB, it is immediately be transmitted to one of 15 ground stations world wide.

EPIRB is programmed and loaded with a unique code for identity before it goes toon board a vessel. The identity includes a 3 digit country code. This is the country that takes responsibility for storing that particular EPIRB’s registration details. When EPIRB is activated in an emergency, the nearest Rescue Coordination Centre (RCC) will receive the message and decode with registration database . Three registration forms are provided, two are for future use and one must be completed immediately.

A latest model EPIRB has advanced system with operation frequency of 406.025 MHz or with Immarsat system using a frequency of 1.6 GHz (International Maritime Satellite system). The code of EPIRB contains,

a) Type of vessel or ship

b) Country of registration

c) Beacon identification-The unique number referred to above.

d) Distress message – fire, sinking etc.

e) Position of EPIRB/vesse