High speed in reduced visibility created a dangerous situation. The Nautical Institute describes a near collision between decommissioned military boats and a passenger vessel in a new Mars Report.
The Nautical Institute gathers reports of maritime accidents and near-misses. It then publishes these so-called Mars (Mariners’ Alerting and Reporting Scheme) Reports (anonymously) to prevent other accidents from happening. This is one of these reports.
Seven decommissioned yet still operational small military boats had been organised to allow the public to have access and enjoy a short ride of approximately thirty minutes in the immediate area of the port. The one-day event was touted as “A Day in Paradise”.
On the day of the event, there was thick fog in the area. The crews of all seven vessels agreed on the route to be followed. To offer the best possible experience for the passengers, the slower vessels would depart first, to be overtaken during the cruise by the fast-moving vessels. Ship A, a 45-metre former missile/torpedo boat capable of high speeds, would leave last.
A first trip was completed in the morning, but the speed of the participating vessels was reduced due to the thick fog. For the second trip, the visibility was slightly better, possibly between 100-200 metres. At one point there was some confusion among the participating vessels. One vessel made several course alterations to avoid a close encounter, bringing it “out of formation”. This was noticed on Ship A, which was at this point making about 30 knots.
Also read: Close call between passenger ships in fog

Master uses app to identify other vessels
The crew on Ship A noticed another echo on the radar, which they could not identify, nor determine in which direction it was moving. The crew were unable to use the automatic plotting device available on the radar as they were unfamiliar with its full function. The master used an app on a mobile phone to try and see if the echo was a vessel with AIS. However, the app did not show vessel symbols.
The crew of Ship A did not realise that the echo was Ship B, which was not part of the event but a regular small passenger ferry making way at a speed of 15 knots.
Ship B’s crew saw that Ship A was on a southerly course and assumed that Ship A would pass portto- port and then astern of them. But then, Ship A turned to port to an easterly course at about 35 knots, bringing it on a collision course with Ship B. When the Master of Ship B saw that Ship A was heading directly towards them, he turned to starboard in an attempt to avoid collision. The bridge team on Ship A saw Ship B at the last minute and were unable to make any changes to their speed or direction. They passed astern of Ship B at about 7 metres distance.
Also read: Unexpected fog throws bridge team into disarray
Investigation findings
The investigation found, among other things, that the reason the speed was not reduced on Ship A was that the bridge team felt the conditions were excellent for radar, where even echoes from small objects appeared clearly on the screen. The bridge team thus felt that they had control of the situation despite the dense fog. However, the high speed meant that the OOW and the Master had very little time to perceive, discuss, and analyse the radar image. They did not understand that they had lost their situational awareness of the surrounding traffic.
Also read: ‘Navigating in fog is not a time to undertake administrative duties’
Advice from The Nautical Institute
- Only good fortune prevented this close call from being a disaster. Given the high speed of Ship A and the fact that there were passengers on the foredeck, an impact with Ship B would probably have resulted in multiple fatalities.
- Once again, high speed in reduced visibility created a dangerous situation. Slow down in fog!
- Using a telephone app to help identify other vessels is not professional nor a recommended practice. Use proper navigation instruments to their utmost.
- Editor’s note:
- This close call is a good example of how luck plays a role in consequences and how every close call is just as significant as an actual accident. Had Ship A started to alter course to port just 0.5 seconds earlier, the vessels would have collided. The lesson to be retained: report and analyse all close calls!
Also read: Fog and single-point failure lead to allision with bridge support
Mars Reports
This accident was covered in the Mars Reports, originally published as Mars 202601. A selection of the Mars Reports are also published in the SWZ|Maritime magazine. The Nautical Institute compiles these reports to help prevent maritime accidents. That is why they are also published (in full) on SWZ|Maritime’s website.
More reports are needed to keep the scheme interesting and informative. All reports are read only by the Mars coordinator and are treated in the strictest confidence. To submit a report, please use the Mars report form.







