Five different ways to call for help on the water

A number of things can influence your ability to get the message out via radio, including battery power and something as simple as water in the antenna connection.

If for some reason you can’t pick up the microphone to call for help, there are a number of other ways to get the message out.

Modern marine VHF radios with a DSC button have the ability to take a lot of the worry out of an emergency situation. DSC stands for digital select calling, which is a DSC-equipped VHF radio’s ability to broadcast a distress signal on VHF channel 70 to everyone within listening range. Better still, once set it will automatically boost the radio’s signal strength, and keep pumping out the distress call leaving you free to tackle the situation.

Once you hold down the DSC button for about three seconds to activate it, every other DSC-equipped boat within range of the DSC signal – about 15-17 nautical miles in ideal conditions – will see details of the DSC distress call on their radio’s screen. Information will include the vessel’s position and a nine-digit “MMSI” code that will help onshore rescue services identify your boat.

DSC will also rebroadcast the distress call on the radio of every nearby boat every three minutes if the radio receiving the DSC alert doesn’t respond.

Impact: DSC takes the “search” out of “search and rescue” by automatically letting everyone know your vessel’s position. However, it doesn’t replace a voice call broadcast on VHF radio, which will provide emergency services with a much clearer picture of how the rescue should be co-ordinated.

If you’re close enough to shore, a mobile phone could be a handy way of contacting a land-based rescue service. However, just don’t think of it as a replacement for a marine radio in an emergency situation.

You can either contact triple zero, or use the number for the nearest coastguard station to raise the alarm. Don’t phone a friend or a relative; they’re not going to know what to do so will only slow down those all-important rescue response times.

Smartphone-based Coast Guard apps such as the NSW-based MarineRescue or Victoria’s SafeTrx – used to easily log on and off with rescue services on each trip – also have hot buttons that hook you straight up with emergency services. Depending on how the app is set up, it can also supply rescue services with the mobile device’s GPS location.

Generally speaking, mobile phones don’t broadcast their GPS position. If you’re picking up the phone to call in the troops you better have a good idea of where the boat is located.

Impact: Think of smartphones as a back-up plan rather than a first port of call in an emergency. You will need to be near a land-based mobile phone tower to get a signal, and remember that the more load there is on a mobile phone tower, the less range it is likely to have – typically sunny weekends and public holidays.

Generally speaking, you will need to carry different flares depending on whether you’re inshore, or off it.

Basic flares include one that produces a large cloud of orange smoke, one that produces a bright red flame, and another that suspends a bright white light below a parachute.

The orange smoke flares work best in daylight and in lighter winds, where the smoke hangs around in a dense cloud to mark your position. On a clear day anyone on the water will need line of sight to spot you up to 2nm (4km) away, but from the air it could be visible from much further away.

The orange flare will burn for about 30 seconds, and is clearly visible for about three minutes.

Red flares are for night use. Light travels a long way across water, and a red one held aloft against the dark sky and water will stand out like the dog’s proverbials. Once again, you need line of sight for the flares to be seen, which on a clear day can be spotted about 15 nautical miles away on the surface of the ocean, or from tens of miles away from on the air.

A red flare will burn for about 60 seconds. It will also burn so hot that you can seriously hurt yourself if you're not careful.

Note that if you’re low in the water and there is a big swell, you won’t always be visible to searchers looking for you. Generally speaking, you and another boat on the water will both be on the crest of a big swell in about one in every seven sets, with the other six with you, or your rescuers, caught inside the sets and out of a direct line of sight.

This is important if you’re attempting to rescue someone along the coast at night; the lights of towns scattered along the coastline will be visible at the top of every swell, whereas someone in the water holding a light source will only be visible occasionally about one in every seven times you cross a swell.

Distances to lights are also very hard to judge on the water, so someone may be a lot further away than you think.

The caps of orange smoke and red incendiary flares are marked with either an O (for orange) or X (for red) to help you distinguish between them in low light or darkness.

Parachute flares must be carried if you’re heading a certain distance offshore, and similar to a firework they hang high in the sky and slowly drift down.

The ones used in marine applications shoot up to 300 metres into the air and are visible from a long distance away, even in daylight.

Be sure to familiarise yourself with how to set off your flares.

Orange smoke and red incendiary flares are set off by pulling off a cap on top of the flare, pulling the top-mounted igniter and holding the flare from the bottom (that last point is important because the red flares get very hot as they burn).

To launch a parachute flare, the igniter is likely to be down the bottom, and not up the top.

Rescues have sometimes been hampered because the parachute flare was deployed upside-down, and the flare has fired into the boat in distress rather than into the sky where rescuers can see it.

Impact: Flares give you good visibility day or night, but their effectiveness is entirely dependent on conditions. Learn to identify the differences between them in the dark.

Satellites in the sky are always listening. That’s a handy reassurance if you ever need to set off either an EPIRB or a personal locator beacon.

It’s important to realise that if you do set off one of these devices, the signal will go to the Canberra-based Australian Maritime Safety Authority. It will then contact emergency services in the area around the EPIRB/PLB’s location to kick off a rescue.

That’s the one big plus of satellite-based systems – statistics show the chances of survival increase significantly once the mayday call reaches a land-based rescue authority.

EPIRBS and PLBs work best when they have a wide, open view of the sky, so once you activate them ensure they’re tethered and floating free of the boat or held away from your body with the antenna as upright as possible to improve the satellites’ ability to pinpoint your location quickly and accurately.

If you’re looking to rescue someone who has called in the troops via an EPIRB or PLB, it’s important to understand that the reported GPS position of the vessel could be up to 15 minutes old by the time it reaches you. This means you may need to allow for wind and current when thinking about where the search zone may have moved to over time.

Impact: Setting off an EPIRB or PLB can greatly improve your likelihood of rescue, but are not as set-and-forget as you’d think.

A V-sheet is a bright orange, rectangular sheet of reflective plastic – meaning it will float – with a big letter “V” in the middle. Cheap, and often sold with a mirror that can be used for signalling, it’s an effective way to call in help – but only when the conditions suit.

Impact: V-sheets work well in clear daylight conditions, or at night when searchlights are scanning the water. Because they float, they can stay with you in the water – if ever it comes to that.

Use whatever you have. Tie a T-shirt to an oar or boat hook and wave it slowly overhead to attract attention.

If you’re in sight of another boat, face it and slowly raise and lower your arms – it’s an internationally recognised signal that all is not right.

Use something shiny or reflective as a mirror to flash sunlight at nearby vessels, or to shore.

If you have a horn, sound it repeatedly.

If the worst happens, stay with the boat for as long as it floats.