Definitions of Launch Terminology

A brief explanation of the terms used in the Launches and Callout pages.

Recent Launches


Callouts 2001-2008

Callouts 1988-2000

Callouts 1943-1987

Callouts 1865-1942


E.P.R.I.B. - Emergency Position Radio Indicating Beacon
An E.P.R.I.B. is designed to help rescuers locate you in an emergency situation, and these radios have saved many lives since their creation in the 1970s. A modern E.P.R.I.B. is a sophisticated device that contains a 5-watt radio transmitter operating at 406 MHz, a 0.25-watt radio transmitter operating at 121.5 MHz and a GPS Receiver. Once activated, both of the radios start transmitting. Approximately 24,000 miles (39,000 km) up in space, a GOES weather satellite in a geosynchronous orbit can detect the 406-MHz signal. Embedded in the signal is a unique serial number, and, if the unit is equipped with a GPS receiver, the exact location of the radio is conveyed in the signal as well. If the E.P.R.I.B. is properly registered, the serial number lets the Coast Guard know who owns the E.P.I.R.B. Rescuers in planes or boats can home in on the E.P.I.R.B using either the 406-MHz or 121.5-MHz signal. Older E.P.R.I.B. did not contain the GPS receiver, so the GOES satellite received only a serial number. To locate the E.P.R.I.B, another set of satellites orbiting the planet in a low polar orbit could pick up the signal as it passed overhead. This would give a rough fix on the location, but it generally took several hours for a satellite to come into range.
POB - Persons on Board
MV - Motor Vessel, essentially any boat with an engine.
MFV - Motor Fishing Vessel, essentially a trawler or other powered fishing boat.

Hoax - A plan to deceive someone, such as telling the Coastguard there is a someone in trouble or danger when there is not one. To deceive, especially by playing a trick on someone.

This endangers the lives of everyday people as well as the crew. There could be others in danger that the lifeboat cannot respond to as they are dealing with a hoax call.

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