Collision and near-miss caused by guard vessel
- Safety Flash
- Published on 18 December 2014
- Generated on 20 February 2026
- IMCA SF 19/14
- 3 minute read
A Member has reported two incidents, one involving a near miss, the other involving a collision between two vessels, with the common factor between them being the way in which a guard vessel was managed. The incidents occurred during inshore diving operations on a wind farm under construction.
Near-miss – Yacht nearly collided with diving vessel at anchor
In the first incident, a private yacht narrowly missed colliding with an anchored vessel involved in inshore wind farm diving operations, with a diver in the water. A sailing yacht was encountered, with no name or home port visible on the hull. The spinnaker sail was fouled, and the crew of the yacht were on deck trying to clear it. The yacht drifted across the 500m zone and barely cleared the port forward anchor buoy.
Our Member noted the following:
- The guard vessel lay at anchor and did not respond appropriately to the approaching yacht, only calling the yacht when it entered the 500 metre zone.
- The yacht was called by the guard vessel on channel 16 – there was no response.
- The guard vessel did not call the diving vessel to alert it of the approaching yacht.
- The crew of the yacht were unaware of their surroundings.
- The yacht’s rigging was fouled and the crew onboard where trying to regain control.
- Given the relatively low speed of the yacht there should have been plenty of time for the guard vessel to see it, hail it and following lack of radio response from the yacht, move to intercept it, or to alert its crew to the impending danger, by sounding a fog horn or alarm whistle.
Our Member suggested that this incident might have been prevented by:
- A better look out from the guard vessel.
- Pre-emptive action from the guard vessel before intruder came into exclusion zone.
Collision between guard vessel and diving vessel
In the second incident, there was a collision between a guard vessel/anchor handler and a vessel at anchor involved in diving operations on an inshore wind farm. The incident occurred in daylight when the guard vessel/anchor handler was asked to come alongside the vessel at anchor. The guard vessel/anchor handler approached the anchored diving vessel not as requested (from aft) but from forward, barely avoiding the forward anchor wire. The guard vessel/anchor handler collided with the diving platform, distorting the diving basket, damaging the clump weight wire and possibly damaging the frame itself (which had to be to be checked later and the complete system re-certified).
Our Member noted the following:
- The master of the guard vessel/anchor handler was not sufficiently in control of the vessel when manoeuvring.
- The crew of the guard vessel/anchor handler ignored communications and put the guard vessel/anchor handler at great risk, ignoring the expressed wishes of the bridge crew of the anchored vessel.
- The guard vessel/anchor handler was temporarily removed from duty.
Our Member took the following actions:
As recommended by their client, our Member arranged for a replacement master for the guard vessel. This was done and the guard vessel has returned to work with a new master, and the working relationship between the two vessels has been very good.
Related safety flashes
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IMCA SF 10/11
16 September 2011
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