Wednesday 5 February 2014

VHF Marine Radios and Sea Kayaking

I carry a safety kit every time I go on the water and a component of that kit is my handheld VHF Radio.  I have used the VHF Radio in a potential emergency situation, and countless times to receive (weather reports) and communicate information where phones and other forms of communication were not possible.

A situation occurred on a committed crossing we were undertaking where we needed to utilise a VHF Radio.  We were just over 80 kms off shore heading for a remote coral atoll around 15kms away.  We had been paddling in worsening conditions with 4 meter seas, 2 meters of cross-directional waves, over 30 knots of beam wind and we were 13 hours into the crossing when a large fishing trawler appeared bearing directly towards us.

We put in a securite call warning the trawler of our presence.  We didn't get a response and were concerned that the boat would have been on auto-pilot with the crew working the nets.  We attempted to set off a flare whilst putting in a further securite call.  The flare failed to ignite, but on a further securite call attempt, the trawler skipper responded that he had a visual on us and he was bearing away - potential disaster adverted.

An interesting point in this story was that the Coast Guard back on mainland Australia had listened in to our call and contacted the ship post incident asking about our status, etc.  I'm not sure of technically how a 5W radio was able to be picked up around 90-100 kms away.  The story continues as the Coast Guard got a little excited about 3 kayakers being this far out to sea and contacted the island we were heading to - but they were expecting us and were able to pacify the authorities and whilst our trip took a few more hours than we had expected, we arrived safely, and in need of a cold beer.

According to the Wiki, a mounted aerial on a small boat (close to sea level) will only broadcast around 5 nautical miles, whereas a ship might get 60 Nautical Miles.  This means you can't rely on your VHF alone to get you out of trouble.  These distances are more a guide for operating on working channels, such as channel 69 which is our 'club' channel - interesting to note that the Australian Navy also operates on this channel according to some documentation I came across on the web.  In Australia, our Coast Guard have setup a series of Repeater Beacons which enhance the distance you can communicate on some channels.

If you are looking to purchase a VHF Marine Radio, there are a number of different options and a range of prices to match.  My minimum requirement is to have a 5 Watt Radio - the higher the wattage the further distance the signal can be broadcast - noting that the VHF signal works on a ground wave so line of sight comes into this equation.  To reduce the initial outlay, I carry my relatively cheap non-waterproof VHF in a waterproof pouch which also extends the life of this device (electronics and salt water don't mix!).

It pays to at least read the VHF Marine Radio handbook and better still, to attend a course which are run through our local VMR and Coast Guard stations.  Most hand helds have the the ability to monitor 2 or more key channels and have a keyboard lock so you don't inadvertently change channels.  You need to have a good understanding of your VHF and its limitations before heading out on the water!

Happy Paddling!

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