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Centralizing the alert, structuring the message, locating the right center: these are the points that this application seeks to cover, in an environment where the rescue chain depends on multiple players.
Identifying the right SAR center: an operational challenge for offshore navigation
When a yacht leaves territorial waters, it quickly changes SAR zones. Each sector depends on a different MRCC or JRCC, with its own procedures and resources. And this is where things get complicated. In a degraded situation, the crew needs to know who to contact, and how. An error in the center or a delay in identification can delay the launch of emergency services.
The CH16 application provides a map of SRR zones, with automatic identification of the center responsible. This is particularly useful for ocean-going or long-distance cruising, especially on transatlantic voyages where several jurisdictions are involved. Each rescue center can be contacted by phone or e-mail directly by clicking on it in the application. This avoids transcription errors.
The application even works offline, when there's no network. MRCC contact details are updated once a month, when the cell phone has a connection. The database used is identical to that of the website, which is widely used by all the world's players.
Structuring a compliant MAYDAY message, between GMDSS standard and field reality
A distress message follows a precise structure, defined by the IMO and GMDSS. However, under stress, the order of information or its clarity deteriorates. The application includes a MAYDAY and PAN PAN message generator. The principle behind the message generator is to guide the user through the sequence, automatically integrating ship and position data.
The application even offers voice playback of the message. In the application settings, you can also record the name of your boat. In this way, the PAN PAN or MAYDAY is read out in full. Simply position your cell phone in front of the VHF and start playback. All parameters, message cause, position... are transmitted at an official playback rate.
Man overboard, from GPS tracking to effective recovery
MOB mode records a GPS position and provides guidance to the drop-off point. This function is now available on many trackers. But with a mobile application, you always have your phone in your pocket. The main benefit lies in complementing an existing system. On a small unit without advanced electronics, or in light navigation, it can provide an additional landmark.
Passage Plan and MCCR notification, anticipate rather than suffer
Passage Plan introduces a different logic. The aim is no longer to react, but to anticipate. The application allows you to declare a route and notify the SAR centers concerned, via an e-mail written in their language. This approach is part of a practice already familiar to experienced navigators, who transmit their route intentions. The benefits are twofold. On the one hand, the centers receive information in advance. On the other hand, in the event of a problem, the search can start more quickly.
From Global SAR to CH16, a field-based operational base
CH16 follows on from Global SAR, a database developed by two CROSS watch leaders. Their initial observation was that MRCC contacts were incomplete or obsolete. The aim of the project was to provide more reliable access to rescue center contact details. Already in use in more than 120 countries, this tool helped to reduce the time needed to establish contact.
And this logic is reflected in the mobile application. We're moving from a consultation tool to an embedded tool, with automated messages and integrated navigation functions.
The application is free and can be downloaded from the App Store (an Android version is planned for May 2026). An ad-free version, which does not add significant functionality, is available without subscription at a unit price of ?5.99.
