M2018-04 Incident between a pilot boat and a missile boat off Emäsalo

In the early hours of the morning of Saturday, 1 December 2018, the missile boat Hanko of the Finnish Navy was running on the west side of Emäsalo southwards on the Sköldvik fairway. The steering crew used visual navigation, supported by the integrated navigation system. The visibility was good. The missile boat was not sending AIS data. Earlier, the missile boat had reported its future area of operations to the VTS Centre.

The pilot boat L239 set out from the Emäsalo pilot station to pick up a pilot from the Port of Sköldvik. L239 setting out was detected on the bridge of the missile boat Hanko immediately after it departed the pilot station. The crew of Hanko was aware that their vessel was on the left side of the centre line of the fairway.

Kuva 1. The routes of the missile boat Hanko and the pilot boat L239 from 02.16 onwards. (Base map: Finnish Transport and Infrastructure Agency, drawing: SIA)


Upon coming level with Esthamnsudden, L239 turned to true bearing of 329°, taking the pilot boat to the left side of the centre line of the fairway. The speed of the pilot boat was around 25 knots (around 45 km/h). The crew of the pilot boat did not notice the missile boat on the fairway. At some point, the operator of the pilot boat noticed a radar echo that he interpreted to be a flock of birds. The missile boat made several relatively minor course changes in order to move to the right-hand side of the fairway and meet the pilot boat in accordance with the maritime rules.

The assumption on the missile boat that had now moved to the right-hand side of the fairway was that the crew of the pilot boat had noticed the missile boat. Upon realising that the pilot boat's motion factors remained unchanged, the officer of the watch stopped the missile boat. The pilot boat was almost half a cable length (around 80 metres) to the left of the centre line of the fairway and coming directly towards the missile boat. At the same time, the operator of the pilot boat noticed an unidentified object in front of him, turned on the spotlight, identified the object as a vessel, reduced speed and performed a tight evasive manoeuvre to the right. The vessels passed each other at a distance of around 0.2 cable lengths (around 40 metres).

In order to avoid similar accidents and reduce their consequences, the Safety Investigation Authority recommends that

- The Navy perform a risk assessment of the significance of the undetectability of its operations to the safety of its own and other vessels and to the possibilities of the VTS to monitor the general safety of the maritime traffic in its area and to prepare instructions for the measures necessary for the management of the identified risks.

- The Navy and Finnpilot Pilotage Oy agree with the Finnish Transport and Communications Agency on procedures for reporting incidents for the overall development of maritime safety.

M2018-04 report (in Finnish) (pdf, 2.08 Mt)

Published 24.10.2019