Coastguards warn against users of Decca displays –

Coastguards warn against users of Decca displays Published:  21 September, 2005

THE UK coastguard service warned today that some GPS systems are capable of displaying emulated Decca coordinates and this could put lives at risk.

They say some GPS displays are quite capable of outputting positions in Decca format. Apparently, some fishermen are using Decca coordinates as their preferred display option, perhaps because their regular fishing grounds (ones that they, or their forebears, have fished for decades) are most familiar to them as Decca lanes and positions.

The coastguards say that recent investigations have revealed that a few GPS manufacturers still offer Decca display as an option on their systems. However,this has serious safety implications in the event of an emergency – especially in a rapid capsize or sinking where the crew of a vessel may only be able to make a short distress call and might be unable to select from Decca to latitude and longitude display.

Fishing, and any other vessels using Decca coordinates, must, they say,understand that this is not an acceptable position reporting system as Decca lattice charts are no longer produced by Hydrographic

Offices (Decca having been switched off in year 2000) and the

Coastguard no longer holds charts to plot Decca coordinates onto.

Also, in the event of an emergency, use of Decca coordinates may

significantly and dangerously impede rescue operations. Users of

Decca displays could be putting their own, and others, lives at risk

by continuing to use Decca coordinates.

The Maritime and Coastguard Agency recommend fishermen to use

Latitude and Longitude as the default display option on their GPS.

Roly Mckie, Operations Officer, Headquarters Maritime and Coastguard

Agency said:

“Coastguard advice to all users is not to use positioning systems or

formats that are no longer universally used or understood.It is advised that all mariners use the distress alerting systems

available to them through the Global Maritime Distress Safety

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