High speed and compromised manoeuvring caused Milano Bridge accident
The container ship Milano Bridge had failed to slow down as it attempted to berth in Busan New Port on 6 April 2020, causing it to crash into, and demolish a gantry crane, investigations showed.
South Korea’s Ministry of Oceans and Fisheries (MOF) said in a 7 May statement that the accident happened when the 13,870TEU vessel, operated by Ocean Network Express (ONE), also had its propeller just touching the water surface, weakening the vessel’s manoeuvrability.Video Player00:0001:30
The MOF’s Korean Maritime Safety Tribunal’s (KMST) investigations showed that Milano Bridge entered the port with about one-third of its propeller exposed above the water surface because it was not carrying sufficient ballast water. Milano Bridge was not carrying cargoes at the time, having departed from Zhoushan DDW PaxOcean Shipyard in China, after undergoing repairs.
KMST noted that Milano Bridge approached the pier 2 at a speed of 8kn, which was higher than the usual speed of 6kn when berthing. Wind speed at the time was 5 to 8m/second, which is considered normal.
Milano Bridge brushed against another container ship, Seaspan Ganges, before knocking into one of three gantry cranes along the pier.
Besides analysing the voyage data and closed-circuit television footage at the accident site, investigators interviewed port pilots and ship captains, in addition to conducting field work.
Investigators also tried to simulate the operations of Milano Bridge at the time of the accident, using the voyage data and statements from related persons, as well as similar weather, tidal and wind conditions.
The results of the simulations showed that when the propeller is fully under water, the manoeuvrability of the ship is improved and there is a better chance of avoiding accidents.
KMST also calculated that the accident could have been avoided if Milano Bridge had slowed to less than 7kn when approaching the pier.
KMST investigator Lee Chang-yong said, “We’re investigating to determine the accident cause and prevent a recurrence. Apportionment of responsibility will be done through a later review.”
Milano Bridge is now undergoing repairs in Dalian Shipbuilding Industry Company’s yard in China.