When bridge control is lost despite the vessel’s systems remaining operational, human error can appear to be the obvious explanation. However, accidents rarely result from a single mistake. Procedures, system design, fatigue, workload, communication and established working practices can all contribute to conditions in which errors become more likely. Understanding these factors is essential to preventing similar incidents.
Human error is a normal and often predictable part of operational activity. The challenge for shipping companies is to identify where errors may occur, understand the conditions that increase their likelihood, and put measures in place to help crews avoid them.
Risk assessments for safety-critical tasks should therefore consider not only potential failures but also the conditions that influence human performance. These are commonly known as performance-influencing factors (PIFs).
Several such factors have been identified in accidents involving apparently incorrect system settings by crew members. Although the settings themselves may initially appear to explain what happened, closer examination often reveals underlying organisational, operational and design issues.
When routine operations become risky
Repeatedly performing a task without incident can create a false sense of confidence. This appears to have contributed to an incident involving a bridge-wing joystick, in which an established procedure for transferring control to the bridge wing was not followed by experienced crew members who had performed the task many times.
Systems that operate reliably under normal conditions can encourage complacency, leading even experienced operators to treat safety-critical actions as routine. Familiarity may reduce the likelihood that established checks are performed consistently.
Shipping companies should consider reviewing bridge-team briefing practices before vessels enter confined or congested waters. These briefings provide an opportunity to reinforce the importance of correct control settings and confirm the responsibilities of each team member.
When established practice replaces formal procedures
Working practices can gradually become normalised on board, even when they differ from documented procedures. This appears to have occurred in an incident involving incorrectly configured steering gear, where crew members had developed their own understanding of the appropriate arrangement for emergency steering.
Such informal practices can introduce hidden risks that remain undetected until circumstances combine to produce an accident.
Regular emergency steering gear room drills, which are required every three months, provide an opportunity to reinforce correct procedures, verify crew understanding and identify deviations from established practice.
The importance of signage and ergonomics
The same steering gear incident highlighted how signage indicating emergency operation may contribute to misunderstandings. In the bridge-wing joystick incident, panel illumination created uncertainty about whether the joystick was active.
Clear signage, intuitive controls and effective visual indicators are essential to helping operators identify which control station is active and where control authority lies. Human-machine interfaces should communicate system status unambiguously, particularly during safety-critical operations.
Making procedures effective in practice
Procedural weaknesses also contributed to several incidents. In one case, shortcomings in the transfer of control between the bridge and engine room contributed to a fishing vessel engaging full-ahead propulsion while alongside.
In other cases, bridge reference cards contained steps that could have prevented an incident from escalating, but crew members did not recall, understand or apply them.
Procedures must therefore be designed for practical use under operational pressure. Critical instructions should be easy to locate, clearly worded and sufficiently concise to support rapid decision-making when time is limited.
The effects of workload and fatigue
Several incidents developed within minutes, placing crew members under considerable cognitive pressure. When control appeared to be lost, operators had to diagnose the problem, assess the risks, communicate with colleagues and take corrective action simultaneously.
These circumstances demonstrate how quickly human performance can deteriorate when crews encounter unfamiliar situations under pressure.
Fatigue was identified as a contributing factor in at least two cases. In an incident involving a collision between naval vessels, acute fatigue affected the crew’s response to a perceived loss of steering. The investigation also found that fatigue was not being actively addressed.
Although investigators referred to the rest requirements under the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW), recorded rest periods do not necessarily reflect the conditions experienced by crew members in practice. Effective fatigue management requires attention to actual working conditions, not simply compliance with recorded hours.
Communication and shared responsibilities
Distraction and interruptions to task-related attention contributed to some of the incidents. However, their influence varied between cases.
In a grounding incident involving a reef, investigators did not identify distraction as a contributing factor, despite the watch officer being questioned about drills approximately one minute before a critical course alteration. This followed a period in which the officer had repeatedly switched the vessel between autopilot and manual control.
In the bridge-wing joystick incident, the master and second mate each assumed the other would perform the final check to confirm that the joystick was active. The absence of closed-loop communication meant that neither person explicitly confirmed completion of this safety-critical step.
These cases highlight the importance of clearly assigned responsibilities and positive confirmation when transferring control or verifying system status. Assumptions should not replace explicit communication during critical operations.
Human-machine interface and system design
Modern bridge systems can improve operational safety, but greater integration can also make it more difficult for operators to determine which system or control station has authority. Several incidents involved precisely this type of uncertainty.
An investigation into a fishing vessel that engaged full-ahead propulsion while alongside examined safeguards intended to prevent unsafe synchronisation between control stations. The vessel’s classification approval had relied on an interpretation of applicable rules and factory acceptance testing.
This illustrates a potential gap between demonstrating compliance during approval and ensuring that systems remain intuitive and safe in real operating conditions. A system can satisfy technical requirements while still creating opportunities for confusion during actual use.
Design improvements should prioritise clear indications of operating modes, safeguards against unintended transfers of control and interfaces that minimise ambiguity. Feedback from crew members can help identify usability problems and determine where ergonomic or interface changes are needed.
Shipping companies should also encourage a culture in which personnel feel comfortable reporting concerns about safety-critical equipment and questioning potentially unsafe practices.
Training, familiarisation and learning from near misses
Several investigations identified shortcomings in crew familiarisation or understanding of the systems in use. Even experienced mariners may rarely encounter unintended control transfers or confusion over operating modes during normal operations.
Written procedures remain important, but safety-critical systems also require practical training. Crew members should have opportunities to recognise and recover from unexpected losses of control while the underlying systems remain operational.
Drills commonly focus on conventional mechanical or electrical failures. Training should also cover atypical scenarios caused by incorrect system settings, including situations in which operators must determine which control station or system is actually governing the vessel.
Near misses provide another valuable source of learning. In the bridge-wing joystick incident, investigators identified earlier occurrences involving the same system under previous ship managers.
Examining near misses with serious potential consequences can reveal performance-influencing factors before they contribute to a major accident. This approach helps organisations move beyond attributing incidents to individual mistakes and identify the wider conditions that make those mistakes more likely.
Improving safety through system-wide learning
Learning from user experience has long supported improvements in aviation safety. Applying similar principles in shipping presents additional challenges because vessels and bridge systems are less standardised than aircraft. Crew members moving between ships may therefore need to adapt to different control arrangements, interfaces and operating procedures.
Several incidents demonstrate how difficult it can be for crew members to diagnose unexpected system behaviour. In some cases, corrective actions aggravated rather than resolved the problem.
One possible source of improvement is the use of clear, context-sensitive verbal warnings, similar to systems used in aviation. Timely alerts that identify the active control mode and provide unambiguous guidance could help crews respond more effectively to unexpected system configurations or genuine equipment failures.
Ultimately, preventing bridge-control incidents requires more than reminding crew members to follow procedures. It requires organisations to examine how equipment is designed, how tasks are performed, how responsibilities are communicated and how crews are trained. By addressing these factors together, shipping companies can reduce the likelihood of human error developing into a serious accident.
