We hope you may never have to refer to this West Advisor while at sea because it means that your boating day is in the process of getting ruined or, worse, that you are in grave and imminent danger. A Mayday call indicates that life and property are at acute risk. It is warranted in cases of serious damage, danger of losing the vessel, life-threatening injury or illness of someone aboard. A distress call on Channel 16 should follow a certain protocol to make sure it is clearly understood and contains the necessary information that will guide rescuers to you as quickly as possible. We’ll run through the protocols below. First, you should understand why your VHF radio is critically important in a boating emergency.
Your smartphone is not a substitute for a marine VHF radio. It is a “narrowcast” device and cannot broadcast your call for help, so nearby boats will not hear your call or know you need assistance. Even if you know and call the local Coast Guard phone number, they usually have no way of knowing where you are unless you tell them, and if your mobile phone call is dropped, they may be unable to call you back. Also, mobile phone range is often no more than a few miles, but even your handheld VHF is likely to be heard at distances of 20 or more miles. Why take chances and delay the arrival of the rescue you need? With your VHF radio you can call the Coast Guard directly. Because there are no second chances in life, there is no substitute for a VHF radio.
DSC distress calls are sent automatically with the push of a button. They tell the Coast Guard who you are (the name of your boat) and where you are (Lat. and Long). With DSC and Rescue 21, your call gets through, even in difficult conditions. Your digital signal can be received and accurately decoded under conditions where voice messages are difficult or impossible to understand. Your message is automatically stored and displayed on every DSC radio that receives it, and the Coast Guard’s response automatically switches your radio to Channel 16 for voice communication.
DSC distress calls summon assistance quickly, because virtually all Coast Guard units monitor DSC distress calls, so all Coast Guard vessels in radio range of your boat are alerted immediately. Since they know your precise location, the Search phase of Search and Rescue is greatly reduced or eliminated. The help you need arrives sooner, and Coast Guard crews spend less time exposed to hazardous weather conditions.
NOTE: Your VHF radio (and everyone else’s) MUST be on and tuned to Channel 16 whenever the boat is in motion unless you’re communicating on another channel. This may save your life or someone else’s.
Since using DSC can save your life, most of us will want to equip our boats to use DSC for all our VHF communications, especially for making a distress call. How easy is this? Only five items are needed:
Simple, right. You obtain your nine-digit MMSI number, enter it into your radio’s memory, and connect your VHF radio to a GPS receiver, which has to be turned on. To obtain and register your MMSI number, the Coast Guard recommends visiting the website boatus.com/mmsi and following the instructions. The registration is free.
Here’s the problem. Boaters are not following these simple steps for installing this common-sense safety gear. Here is Coast Guard Rear Admiral R. E. Day (Feb. 23, 2011):
“Of the roughly 100 digital selective calling distress alerts we are now receiving each month, approximately nine out of 10 do not have position information (i.e. do not have a GPS navigation receiver interconnected to their DSC-equipped VHF radio), and approximately six out of 10 have not registered their MMSI.
Despite the promises DSC technology offers in significantly reducing the alerting and search time for mariners in distress, there’s little a Coast Guard watchstander can do after receiving a distress alert with no position information, using an unregistered MMSI, and having no follow-up voice communications.”
Boaters, this is a serious problem. Please provide the information the Coast Guard needs to rescue you in an emergency!
Here are the steps to set off a distress call that will get the job done:
A proper DSC setup for your radio is as important for safety as the fire extinguisher, first aid kit and life vest in this photo.
When the Coast Guard receives your DSC distress call, the watchstander on duty is alerted, the Coast Guard’s DSC signals your radio to switch to Channel 16, your radio announces receipt of the Coast Guard’s signal, and the Coast Guard establishes voice communication with you.
When your MAYDAY call is answered, respond with the name of your boat, the latitude/longitude numbers from your GPS, and why you need help.
All DSC radios receiving a distress call immediately sound a distinctive alarm, and automatically switch to Channel 16 for voice communication.
If you didn’t want to make a distress call.
Your radio will indicate that the call has been sent, indicate that the station you called has received your call and switch to the working channel you had selected before you made the DSC call. The station you called will switch to the working channel you chose. You can communicate with the station you called to confirm that everything is working properly.
This online presentation developed by the US Coast Guard and the BoatU.S. Foundation is simply the best summary of VHF and DSC radios we have ever seen: How they work, Rescue 21, distress calls, three types of DSC, Pan Pan/Securite/All Ships, etc. It includes a VHF/DSC radio simulator that even has a working squelch control.
Spend 37 minutes and 25 seconds watching this online tutorial, and you will become a safer and more knowledgeable VHF radio operator. Can You Hear Me?