THE AUSTRALIAN Transport Safety Bureau has released a preliminary report that details an incident at Devonport in January in which the cement carrier Goliath allided with two berthed tugs.
The report describes in great detail the Goliath’s entry into the port, radio calls with both the Devonport vessel traffic service and a mooring lines boat. It also describes the roles and movements of the ship’s crew on the bridge, and the ship’s manoeuvres in the lead-up to the collision.
ATSB chief commissioner Angus Mitchell said the investigation is progressing and the bureau would examine TasPorts’ pilotage exemption process and port procedures, as well as the shore pollution response.
“The ATSB will review and assess the ship’s safety management system and navigation procedures, the effectiveness of bridge resource management on board, and review past incidents involving Goliath,” Mr Mitchell said.
“This preliminary report details factual information established in the investigation’s early evidence collection phase, but it does not detail analysis or findings, which will be outlined in the investigation’s final report,” Mr Mitchell said.
According to the report, the crew received two radio calls from the mooring lines boat Rubicon as Goliath approached the port’s swing basin.
Goliath’s master asked the second mate to respond to the radio calls, so the second mate moved from beside the steering console to near the bridge front console to use the VHF radios located there. Meanwhile, the master commenced a slow turn to starboard in the swing basin as part of the final approach to its berth.
Shortly after, Goliath’s master re-positioned from the wheelhouse to the port bridge wing conning station, from where they manoeuvred the ship using main engine power settings (via the main engine telegraph), the bow thruster and a joystick to input rudder angle commands to the ship’s VecTwin steering system.
“As the manoeuvre progressed, the master felt that the ship was not swinging as expected and was closing with two tugs moored at berth number Three West,” Mr Mitchell said.
To arrest the ship’s movement, the master set the VecTwin joystick to the astern setting and placed the main engine telegraph to first half ahead and then full ahead.
“Ships fitted with the VecTwin twin-rudder steering system can be manoeuvred at low speed with thrust from the propeller re-directed as required by the two rudders, controlled by a joystick,” Mr Mitchell said.
“The system allows astern thrust to be generated using ahead inputs on the main engine without the need to stop the engine and engaging astern propulsion, as would be required for conventional ship manoeuvring.”
With the ship’s speed unexpectedly increasing, the master checked the rudder angle indicator and found that both rudders were still amidships and not at the angles corresponding to the VecTwin joystick’s astern setting.
The master called out to the second mate that the steering was not in VecTwin steering mode and immediately placed the engine telegraph to stop.
At about the same time, Goliath collided about halfway up the starboard side of the tug York Cove at a speed of 4.7 knots.
York Cove was moored outboard of and alongside another tug, Campbell Cove. Both were severely damaged and began to take on water almost immediately.
On board Goliath, the second mate, who at that point was positioned by the wheelhouse door, re‑entered the wheelhouse and found the steering mode selector still in manual steering mode.
The second mate changed the steering mode over to VecTwin mode while the master began to move the ship astern using astern inputs on the main engine to get clear of the tugs before berthing the ship without further incident.
Within about five hours of the collision, both tugs had sunk in about seven metres of water and were subsequently declared constructive total losses. There was no-one on board the tugs, and no reported injuries on Goliath.
