Safety Lessons from Marine Incident Investigation (AMSA Report) No.18 - April 2023
A 2C rescue vessel was preparing to depart a river entrance bar with 11 people onboard. The observed sea state was a wave height (breaking) of 1.4 to 1.8 metres. The entrance bar had a moderate to high level of congestion of jet skis and surfboard riders positioned within the aids to navigation departure leads.
The vessel came within very close proximity to surfers on 3 occasions whilst negotiating the breaking sea conditions. The vessel then broached upon a wave resulting in the vessel heeling to port and becoming unable to be controlled due to the force of the wave.
On 28 May 2022, a 2C rescue vessel prepared to depart a river entrance bar for a special ceremonial voyage. A risk assessment of the entrance bar crossing had been completed earlier in the day, as the increased risk of vessel crossings of the shallow sand banks experienced within the mouth of the bar were well known locally as an increased risk to safe navigation.
The master decided to proceed with 11 people onboard and sounded 3 long blasts on the vessel’s horn on departure. The vessel came into proximity with paddling surfers approximately 40 metres from the entrance breakwall, then the vessel came into proximity with a surfer riding a wave 80-100 metres from the breakwall. The vessel then broached upon a wave, which transversely affected the stability and ability to steer.
At this point the navigation of the vessel’s trajectory was uncontrollable and the vessel was positioned head on to another (third) group of surfers who were also within the outer banks of the wave zone, approximately 150 metres from the entrance breakwall. The vessels port aft quarter contacted a surfer’s surfboard. No surfers, passengers or crew were injured.
The investigation identified the following contributory factors:
- The river entrance (bar crossing) is a dynamic navigation channel of relatively shallow depth and is subject to breaking waves (swell height) and swell roll periods that impact a vessel’s beam as it transits from the inshore safe anchorage to the offshore open waters.
- Recent weather events over the previous 3 months had impacted the departure channel, resulting in an increase of sand/siltation within the bar crossing entrance. The effect was a notable increase in both swell height and the expanded area of the breaking wave impact zone.
- Vessel operations in this location regularly share the area with the public and active surfboard/watercraft riders.
- The organisation did not have a documented risk assessment or standard operating procedure to identify risks and control measures for vessels conducting bar crossings.
- The master failed to keep or maintain a proper lookout. The master stated that the height level of the eastern rock wall and setting sun obscured their vision from the vessel’s flybridge.
- The risk assessment in preparation of the bar crossing was compromised and the master failed to operate the vessel safely.
This hazard situation and outcome were readily identifiable and foreseeable safety risks. The risk assessment performed prior to attempting the river entrance bar transit was ineffective, and the organisation did not have a documented risk assessment process for these types of operations.
Given the master’s restricted view, the master could not maintain a proper lookout. The master has a responsibility to ensure first and foremost the safety of people on and/or near the vessel.