Class F DSC

Chemring Group PLC

At ICS, we believe that Class F DSC equipment is not suitable for fixed radio installations on small craft, and that class D DSC is the minimum specification. Other organisations holding this opinion include the RNLI (lifeboat organisation), HMCG, the RYA (Royal Yachting Association), Marine Safety Agency, Radio Communications Agency and many more. The reasons that Class F was rejected for fixed radio installations in the EN 301025 specification were as follows:-

A vessel equipped with Class F DSC would not hear a Distress message transmitted by a vessel nearby, nor would it receive a subsequent Distress Relay message sent by the coastguard or another vessel. It would simply not be aware of a vessel nearby that was in distress and that it would otherwise be able to help.

	It would not hear Urgency messages from another vessel in need of assistance.
	It would not hear Safety messages transmitted by the coastguards, such as strong wind warnings or other safety critical broadcasts.

Coastguards in Europe are now discussing cessation of watch keeping on Channel 16 from the year 2005. There will then be no way for a yacht to call the coastguard or a harbour authority or any other vessel because Individual calls are not allowed within the Class F specification.

There is no way of testing a Class F equipped radio. It is illegal to test it by sending a Distress call. Testing with a routine call is impossible as it is not provided for. When used in earnest, it might not work!

If fixed Class F radios become generally available, many yachtsmen will buy them because they are cheaper and because they don’t know any better. Because of the above factors, lives would then undoubtedly be lost.

The relevance of Class F is to hand portable equipments which are too small to accommodate a Class D DSC modem but nevertheless require a primitive Distress only transmit capability. If someone is in a liferaft with a hand portable radio without DSC, he has no way (under GMDSS) to attract the attention of a ship on the horizon. There is thus a strong reason for having a Class F specification for portable equipment.

As a company, we are in the midst of installing DSC equipment at 106 coast radio station sites and 22 rescue coordination centres for the UK Coastguards, We are therefore well aware of their communication needs in being able to contact small craft and vice versa. All of this would be impossible with only Class F fixed radios on vessels at sea.

ICS manufacture a class D DSC VHF Radio, the DSC3.