Deckhand Killed After Derrick Chain Fails Without Warning
The Marine Accident Investigation Branch (MAIB) has published its report into the fatal injury of Denver Teleron, a 35‑year‑old deckhand who died when a towing block fell from the scallop dredger Honeybourne III (PD905) after a catastrophic chain failure on 6 October 2023.
The accident occurred at approximately 2345 while the vessel was operating 16 nautical miles south of Newhaven, England. The dredging gear was being recovered when a 32mm chain link in the port derrick quick‑release assembly fractured, allowing the towing block, monkey‑face block and associated gear to fall from a height of nearly 11 metres. Teleron, who had just attached the aft safety chain and was walking forward along the conveyor, was struck on the left side of the head. Despite immediate first aid, radio medical support, and the rapid response of RNLI and Coastguard rescue teams, he was declared deceased at 0125.
MAIB classified the event as a “Very Serious Marine Casualty” and has since issued recommendations to the Maritime and Coastguard Agency (MCA) and the vessel’s owner, Macduff Shellfish (Scotland) Ltd, to address systemic safety issues across the scallop dredging sector.
Sequence of Events Leading to the Fatal Incident
Honeybourne III departed Shoreham on 1 October 2023 to fish the English Channel. On 6 October, the vessel’s crew began their second watch at 1800. At 2330, the mate relieved the skipper, who left the wheelhouse to rest. Shortly afterwards, the mate called the deck crew to prepare for recovery of the dredging gear.
Teleron and another deckhand collected their personal flotation devices and helmets from the whaleback, walked forward along the open deck, and prepared the port dredge beam for recovery. The dredges were hauled to the tipping doors, safety chains were attached at both ends, and the gear was tensioned using the winch inside the wheelhouse.
At 2347, as the mate applied tension to secure the beam, the uppermost chain link in the quick‑release assembly failed. The heavy towing block and rigging dropped onto the conveyor area below. One block glanced off the wheelhouse corner before striking Teleron. His safety helmet was dislodged during the impact.
The crew removed warps and chain from the injured deckhand and moved him to the centre deck. A Mayday was transmitted at 2353. A nearby fishing vessel delivered additional medical equipment before the RNLI and a rescue helicopter arrived. Resuscitation attempts continued for nearly 40 minutes before he was pronounced dead.
The Vessel, Equipment and Operating Arrangements
Built in 1983 and converted to a scallop dredger in 1996, Honeybourne III operated with two derricks fitted with towing blocks suspended by a quick‑release chain and wire system. The arrangement was designed to allow the gear to be jettisoned in emergencies such as snagged dredges that could capsize the vessel.
Each quick‑release assembly used seven links of 32mm Grade‑8 chain routed over a hollow static pin mounted between cheek plates at the derrick head. As the derrick moved between dredging and stowed positions, the chain bent around the pin through angles of up to 180°, imposing complex bending forces on the links. The system had no defined working load limit for the derrick itself, but the chain was rated with a WLL of 31.5t when loaded in a straight orientation.
The MAIB found that when dredges were hauled tight against safety chains, shock loads significantly exceeded normal operational tensions. These loads, combined with chain bending over the pin, created high stress points within the outermost chain link—the link that ultimately fractured.
Findings from the MAIB Investigation
MAIB conducted a comprehensive examination of the recovered components, including the failed chain link, static pin, and associated lifting gear. Several significant defects and safety issues were identified.
Quick‑Release Chain Failure Mechanism
Analysis showed the chain failed in two stages: one shank fractured in a brittle mode, while the other failed ductilely. The failed link exhibited hardness levels above industry‑recommended limits for marine lifting applications, making it more susceptible to sudden fracture under high load. No manufacturing defects were identified.
The HSE Science Division performed tensile and metallurgical testing. While the chain met original EN 818‑2 specifications, its elongation during testing was lower than expected, indicating reduced ductility since manufacture. The chain also suffered heavy inter‑link wear and deformation at critical points.
Finite element modelling by Mechanika Ltd confirmed that routing chain links over a static pin induced unavoidable two‑point bending, high local stresses, and plastic strain in the links. Any wear on the static pin—which was evident on Honeybourne III—reduced the effective bend radius, increasing stress further.
Severe Wear on Derrick Head Components
Significant wear was found on:
- the static pin
- cheek plates
- the crown of the hammerlock shackle
- chain link inner and outer surfaces
The rotating collar had partially seized, meaning directional load alignment was being absorbed by the chain rather than the derrick head structure, accelerating wear across the assembly.
Inspection and Maintenance Deficiencies
The chain and wire components had been replaced in 2022, yet by 2023 the wear was “substantial” and “well beyond acceptable limits.” Monthly inspections recorded by the skipper consistently rated equipment condition as “satisfactory,” even one month after the rotating collar was discovered seized.
The MAIB found that:
- Inspections lacked clear criteria for acceptable wear.
- The skipper acted as the “competent person” without formal training.
- Some inspections may have been informally delegated to crew lacking the required knowledge.
- Macduff Shellfish relied on its skippers to identify faults without independent verification.
The investigation noted that similar failures had occurred within the same fleet, including on the Isla S in 2022, where a chain link fractured in a nearly identical mode.
Safety Management System Failings
The MAIB identified several shortcomings in the company’s Safety Management System (SMS).
Crew Working Beneath Suspended Loads
The lifting plan prohibited standing under suspended loads, yet the vessel’s layout made it nearly impossible to retrieve gear without crew passing beneath heavy blocks. The presence of a defined “safe zone” was not adequately implemented or practical given the conveyor layout and derrick geometry.
Personal Protective Equipment
Teleron wore a snow‑sports helmet not compliant with BS EN 397. Although the MAIB concluded that no industrial helmet could have withstood the force of impact, the presence of non‑approved PPE indicated gaps in enforcement.
The stowage of PFDs and helmets required crew to walk along the deck without PPE whenever called to a gear operation—counter to safety principles.
Wider Regulatory Oversight Issues
The MAIB concluded that the MCA’s oversight of lifting equipment on fishing vessels was not sufficiently robust. Annual surveys relied heavily on shipboard inspection records, and surveyors were not considered competent persons under LOLER. Training for surveyors did not include detailed instruction on recognising lifting gear defects or evaluating competent‑person capability.
Post‑accident MCA inspections of Honeybourne III revealed wear levels and deficiencies that should have been identified during routine surveys.
MAIB Report Conclusions
The MAIB identified seven safety issues that directly contributed to the accident. These include:
- The crew working beneath suspended loads.
- Failure to recognise the inherent risk of chain‑over‑pin arrangements.
- Excessive loading combined with bending stresses in chain links.
- Static pin wear increasing stress concentrations.
- High chain hardness making links susceptible to sudden failure.
- Onboard inspections failing to detect deteriorated lifting gear.
- Ineffective application of the vessel’s Safety Management System.
Additional non‑causal safety concerns included inadequate PPE control, poor stowage of safety equipment, ineffective training of competent persons, and weak regulatory oversight.
Actions Taken Following the Fatality
Macduff Shellfish has undertaken several actions, including:
- Replacing chain‑over‑pin configurations across its fleet.
- Implementing quarterly superintendent‑led lifting gear inspections.
- Updating protocols to prohibit crew beneath suspended loads during winch operations.
- Instituting formal training for crew on lifting equipment inspection.
- Mandating compliant safety helmets and revised PPE stowage positions.
The MCA has completed a focused inspection campaign of scallop dredgers and beam trawlers using chain‑over‑pin arrangements. Findings highlighted widespread deficiencies in lifting equipment inspection regimes and risk assessments.
Recommendations Issued by MAIB
Following the accident, the MAIB issued Safety Bulletin 1/2024, urging owners and operators of beam and scallop trawlers to inspect their vessels’ quick-release arrangements and to make any necessary changes to the equipment or its operation to ensure the safety of crew working on deck.
A safety flyer to the fishing industry was also produced with this report.
Related publications
Safety recommendations do not attribute blame and are intended solely to prevent future accidents.
