Grounding Highlights Bridge Design, Training Problems

steering control

By MarEx 2015-05-12 23:19:38

The Transportation Safety Board of Canada (TSB) has released its investigation report into the April 2014 grounding of the chemical tanker Halit Bey off Quebec citing problems with the vessel’s bridge equipment and crew training. 

The investigation found that steering control from the steering wheel was likely disabled when an unprotected joystick was inadvertently moved, which activated the autopilot override and alarm. The bridge crew was not adequately familiarized with the characteristics of the Halit Bey's steering control system and did not know how to regain control after the autopilot override alarm activated. Once steering control was lost, the vessel veered towards the shore and the crew's attempts to reduce speed and anchor the vessel were unsuccessful to prevent the vessel from running aground.

The vessel was sailing up the St. Lawrence River under the conduct of a pilot when steering control was lost. The vessel veered to port and exited the navigational channel, running aground on the south side of the river off Grondines, Quebec. No damage, pollution, or injuries were reported, and the vessel was later refloated with the assistance of two tugs.

Report Findings

The Halit Bey was proceeding in follow-up mode in restricted waters when steering control was lost, likely when the unprotected non follow-up (NFU) joystick located on the centre steering control panel was inadvertently moved. The design of the Halit Bey's steering gear system was such that touching the NFU joystick activated the autopilot override alarm, even though the vessel was not in autopilot mode. As such, all steering controls on the bridge were disabled, except for the NFU joystick. Without steering control, the vessel veered towards the shore.

The bridge crew, having never encountered a situation of this kind before and not knowing why the autopilot alarm had sounded, were unaware of the available options to regain steering control (the NFU joystick could still be used to steer the vessel or the override reset button on the steering gear alarm panel could be pressed to reset the steering control system). 

In the limited time prior to the grounding, the crew attempted an emergency anchorage; however, the vessel exited the navigational channel and ran aground.

Bridge design and arrangement of equipment

TSB says it is essential that critical bridge systems, such as steering gear control systems, be designed to be straightforward and intuitive for the operator. Good system design will also take into account concepts such as error tolerance, whereby a system is designed to minimize potential errors (by including locking features or protective coverings) or limit the consequences of accidental activation by leaving the vessel in a safe condition should this occur.

On the Halit Bey, the steering gear control system incorporated two different steering gear control panels from two different manufacturers and, as such, had an incompatibility between the panels with respect to the autopilot override. The center control panel was essentially redundant, so the practice on board was to leave it on position 3 (autopilot), which transferred steering control to the right-hand panel. 

However, unbeknownst to the crew, the autopilot override and associated alarm could still be activated by the NFU joystick on the center control panel, even when the vessel was not in autopilot mode. Activation of the autopilot override had the effect of disabling all steering controls on the bridge, with the exception of the NFU joystick itself.

In addition, the steering gear control system did not incorporate protective coverings or locking features on the steering controls, nor was there any information provided to the operator during an autopilot override alarm to indicate which steering controls remained functional or how steering control could be regained. The redundant center control panel was still marked with its original labels, introducing the possibility of confusion for operators unfamiliar with the particularities of the system. 

Finally, the design of the steering control system meant that the wing consoles both had two NFU steering controls, each one wired to a different steering control panel, which unnecessarily complicated the wings mode and had the potential to confuse its operator, given that the steering controls did not have labels to indicate which steering control was connected to which control panel.

In this incident, the autopilot override alarm activated while the vessel was operating in follow-up mode, providing a conflicting message to the crew members that delayed their taking action because it was not clear to them how steering control could be regained in this unusual situation. If critical bridge systems, such as steering gear control systems, are not designed and arranged to be straightforward and intuitive with safeguards to minimize human error, there is a risk that an operator will not be able to respond quickly and effectively in the event of an emergency.

Familiarization with safety critical equipment

In order to effectively use shipboard equipment, crews must know how it operates during routine and emergency situations, as well as how to regain control should it be lost, says TSB. That knowledge may come from technical manuals, familiarization, drills and/or posted procedures.

In this instance, given the characteristics of the vessel's steering control system, it was especially important that crew members be familiarized with all of the various steering modes and controls, as well as what to do in case of an autopilot override alarm. However, the Halit Bey's onboard familiarization did not specifically require crew members to be familiarized with methods to regain steering control following an autopilot override alarm, and the two possible methods were not mentioned on the onboard familiarization checklist. There was no specific information about how to regain steering control posted near the steering stand, and the vessel did not carry an operational manual for the steering control system.

The vessel's emergency steering drills, while complying with Safety of Life at Sea (SOLAS) requirements, were based on a single scenario that did not include testing the steering controls and use of NFU mode, switching between steering modes, or recovering the helm after the activation of the autopilot override. As such, there were limited opportunities for the bridge crew to become familiar with the back-up steering arrangements and the characteristics of the Halit Bey's steering system. 

The bridge officers, none of whom had more than four months' experience on the vessel, were therefore not familiar with all of the various steering arrangements, nor had they previously encountered a situation where the autopilot override had activated while the vessel was not on autopilot. As such, they were unable to respond effectively and regain steering control.

Following the grounding, complete emergency change-over procedures were posted on the bridge of the Halit Bey, taking into account the particularity of the steering control that could be disabled if someone activated the autopilot override mode.

The full TSB report is available here.

Picture credit: Transportation Safety Board of Canada