Most collisions occur as a result of an inadequate lookout or unsatisfactory radar watch. The main cause in several of these events is fatigue. The handing over of watch is also a risk factor. Close quarter situations often occur due to late, unsatisfactory or improper alterations of course and speed.

Facts and Findings

Preventive measures



Between 2004 and 2013 there were 341 collisions that have
incurred a cost more than USD 10,000 with an average cost
of more than USD 900,000 for all vessel types.


H&M collision: Number of claims and category


H&M collision: Vessel location

H&M collision: Number of claims and category, immediate cause



About 70% of the collisions have happened in congested waters and if we include coastal waters that figure increases to 80%. This is an unsurprising statistic as most vessels will be at greatest risk when approaching or leaving port. 


H&M collision: Pilot onboard


H&M collision: Average claim cost & frequency


H&M Collision: Claim cost & frequency as per insured vessel

A pilot has been onboard during 30% of all collisions. This does not mean, however, that the pilot has been at fault – it means that the assistance of the pilot has not been successful. There has been a failure in the communication between the pilot and the bridge team. This is something that needs to be acknowledged and it is important for managers and the pilot organisation to train on communicating correctly within the bridge team.
The bridge team also has to ensure that the pilot is included and the pilot has to ensure that he explains his intentions and agrees upon a plan with the Master. It is when this fails that accidents occur. Correct communication is key. It has to be remembered that the Master is ultimately legally responsible for the safety of the crew and vessel. It is not acceptable for the bridge team to relax and think that the pilot is in charge, as the pilot is an advisor and the final decision always rests with the Master.


H&M Collision: Claim cost & frequency as per insured vessel


The graph to the left shows the average  claim cost for an H&M collision for the chosen vessel types.


Collision cases 

These cases illustrate the problems that precede many collisions; poor communication between both vessels and bridge team members, lack of preparation for the risks, tunnel vision and lost situational awareness have all been recorded. Many collisions happen because the OOW failed to follow correct procedures like calling for extra resources, reducing speed or plotting the target concerned. This is similar to losing situational awareness, which means that the OOW is not fully alert to the factors affecting the vessel at any given time. Reducing speed does enhance situational awareness. As we can see most collisions happen in congested areas, usually while entering or leaving a port. This is of no surprise and emphasises that the bridge team needs to be prepared for the increased risks. Additional resources need to be added to the bridge team when needed, such as another officer or lookout. If the manager has clear procedures on how this should be achieved it will improve safety.

 Synopsis one: 

The vessels collided in congested waters. It was just after dusk, good visibility and calm seas. Vessel A was a container vessel maintaining a speed of 25 knots when it collided with vessel B, which was a bulker. Damages were so severe that vessel B actually split in half. There was no dedicated lookout on vessel A and the OOW didn’t notice the bulker until a couple of seconds before the collision. The OOW on vessel A did not have situational awareness and did not recognise vessel B as a risk.


The OOW on vessel A did not follow the manager’s procedures as there was no lookout at night and also maintained high speed in congested waters. During the OOW’s watch the Master visited the bridge several times but did not voice his concern about the lack of lookout or the speed.

Synopsis two: 

Vessel A was affected by the bank effect and could not complete the alteration around the river bend. This caused the vessel to continue straight forward and it collided with a moored vessel. During the entire river passage vessel A maintained high speed and was positioned to the starboard side  of the river.


The bridge team did not discuss the operation with the pilot in detail and the Master did not have proper charts for the area and did not challenge  the pilot. 

 Synopsis three:

Vessel B totally disregarded the COLREGS. Vessel A did recognise vessel B as a threat and did try to alter course but unfortunately it was impossible to avoid the collision. The situational awareness could have been better on vessel A’s bridge. MRM was not practiced on the bridge of vessel A and there were no specific CPA requirements in the navigation policy. 


Vessel B completely disregarded the COLREGS and vessel A tried to stay clear. It is probable that vessel A could have made an evasive manoeuvre a bit earlier but vessel B’s total lack of following the rules was the main contributor to the collision. 

Synopsis four: 

Vessel A was inbound and vessel B was outbound. The pilot on A had agreed upon meeting starboard to starboard with vessel B. The pilot on A noticed that vessel B suddenly altered to starboard and he could clearly see the red light. The pilot on A called the pilot on vessel B but did not receive any response. The pilot ordered hard to port and to reduce the engine. The Master told the pilot to order hard to starboard and instead stop the engine. The pilot ordered full astern. Shortly afterwards the vessels collided. 


There were confusing orders on the bridge, the Master told the pilot to go hard to starboard after the pilot had ordered hard to port. Communication failed. 

Synopsis five: 

The collision happened during the evening in a traffic separation scheme. The bridge was manned by one officer and a cadet, with no lookout present. For the officer this vessel was much larger than his previous vessels and it had different bridge equipment than that he was used to. The settings on the autopilot were set to a rudder limit of 15° and a rate of turn of 10° per minute but this had not been verified by the OOW when he took over the watch. The vessel altered very slowly but the OOW did not notice this. Visibility was about 6 miles, there was a rough sea, the wind was from the NE at force 8-9, which was almost directly ahead. Vessel A had a course of 030° and a speed of 23 knots. Vessel B was 10 miles away, fine to port and proceeding in the same direction at a speed of 2.5 knots. Four minutes before the collision, vessel B was 1.4 miles away with a CPA of 0.16 miles. The officer hesitated in deciding on which side to pass vessel B. When he had made up his mind, it was too late.


The officer did not verify the settings of the bridge equipment and did not analyse the situation and risks. He had poor situational awareness.

Synopsis six: 

The Master was on the bridge by himself on vessel A. It was after 10.30 in the morning and the weather and visibility was good. The Master noticed a target on the radar which was on the vessel’s starboard bow with a distance of 7m. The Master could also see the vessel through the window. He estimated that the other vessel would pass about 1m ahead. When the vessel was about 5m away he called it on the VHF. He did not receive an answer. He called a couple more times but there was no answer. He monitored the vessel and was sure it would pass his bow. Suddenly he thought the vessel was altering towards him. The vessel was about 1.5m away. The Master had not done anything until now. He switched to hand steering and put the wheel hard to port. Two minutes later the vessels collided.


The Master did not alter when he had plenty of time and room as he assumed the vessel would pass ahead. If it is possible, it is always advisable to alter at an early stage before a situation is created. Vessel A was the give way vessel and should have altered for vessel B.

Synopsis seven: 

Vessel B, a small coastal bulker was the give way vessel as it was on the port bow of vessel A. Just before the collision vessel A did alter to port and vessel B to starboard. This caused the vessels to be on collision course and they finally collided. There was no efficient communication between the vessels as vessel B called on the VHF in Chinese to vessel A but no one on vessel A could understand Chinese. Neither of the vessels made any alteration to prevent the collision.


There was no situational awareness and risks were not properly analysed. 

 IRCA -  in congested waters 

Vessel A was on a southbound course and vessel B was northbound. It was shortly after dusk, there was a light breeze, calm seas and visibility of around eight nautical miles. The vessels were transiting an area of high traffic density with many merchant and fishing vessels. There were a number of small fishing vessels in the area, some moving, others stationary. Vessel A had a group of small fishing vessels on its starboard bow. To stay clear of the fishing vessels, the officer, on watch by himself at the time, decided to keep the vessels to starboard and altered course to port three times over a 20 minute period, while maintaining a speed of 25 knots.

The fishing vessels had bright lights, making it difficult to see any traffic behind them. The Master on vessel A was doing administrative jobs and visited the bridge a couple of times during the watch. The officer on vessel A tried to plot the multiple fishing vessels, but lost the targets or they moved on the radar.

The officer on vessel B was on watch with a designated lookout. The vessel maintained a speed of 12 knots. Vessel B saw vessel A at five miles, or eight minutes before the collision and could see vessel A’s red light on her port bow. The echo trails for both vessels were parallel. He did not recognise that there was a danger of collision.  Five minutes before the collision, vessel B observed that vessel A was showing a green light. The officer on vessel B gave the order to stop the engine and go hard to starboard. The officer did not plot vessel A. Just before the collision vessel A made another alteration to port. Neither of the vessels sounded any warning signals.

The officer on vessel A did not see vessel B until a couple of seconds before the collision and maintained full speed the entire time. The officer on vessel A did not consider slowing down, even when traffic started to become dense. The officer did not have proper situational awareness, as the northbound vessel was not identified behind the cluster of smaller vessels.

For further reading regarding grounding issues, please read our publication Collisions and Groundings that can be found on our Publications.

  Factors fuelling the upwards pressure on hull premiums  

  Collision avoidance, Narrow margins leave no room for error 

  Collisions in majority amongst expensive claims 

  Collisions cause costly claims 

  Human error - a common cause in collisions 

  This is AIS