ATSB confirms steering failure grounded Iron King

Steering gear failure has been identified as contributing to the grounding of 161,167 dwt Iron King, which blocked the entrance to Port Hedland for about 12 hours on July 31.

An Australian Transport Safety Bureau (ATSB) investigation found that the ship had earlier that year had her steering gear overhauled but it had lost pressure because of a leaking valve while she was departing Port Hedland.

The 1996-built vessel was fully-laden, under pilotage and being assisted by four tugs on her way through the channel.

The ATSB found that the rudder was unresponsive and that she veered too far to starboard.

The ship subsequently grounded and was refloated on the next high tide.

The ATSB investigation found that a leaking actuator relief valve limited the hydraulic pressure in the steering system.

"It was also found that it was normal practice for assisting tugs to be let go before departing ships reached Hunt Point," the ATSB said.

"The pilot directed the tugs to make fast to the ship again, but they were unable to do so before it grounded.

"The master was not aware of the appropriate emergency steering system change-over procedure and the pilot had not been provided with training in the implementation of a suite of risk analysed responses to predictable emergency scenarios in a simulated environment."

Port Hedland Port Authority has since commissioned a simulation of the incident to train its pilots for such a scenario.

The port authority's work in this area found that, in such situations, even with the tugs made fast, the 65-tonne bollard pull tugs were of "marginal" benefit.

A full towage review is expected to be completed later this year.

The ATSB said it anticipated "that tugs more suited to open water operations and dedicated active escort tugs will be among the report’s recommendations".