Last week, the Emma Maers had to abort its voyage after it was found the vessel was making water. Currently, the investigation is still ongoing, but Maersk Line has already shared the repairs may take considerable time.

Damage to Stern Thruster

Initial inspections by divers show that the water ingress was caused by damage to one of the stern thrusters. Thrusters are used for improving the vessels manoeuvrability and consist of a shaft tunnel fitted with a propeller delivering sideways thrust. It is now known that several propeller blades have broken off and there is severe damage to the propeller mounting, resulting in a crack in the forward stern thruster tunnel which caused the ingress of water.

The water flooded the engine room which consequently led to the loss of main engine power, and Emma Maersk was towed to the quay at Suez Canal Container Terminal.

Isolated Incident

While it is still unclear what caused the damage, the company has ruled out any human error by the crew and still considers this an isolated incident. To be safe, however, the other vessels in the E-class fleet have been instructed not to use their stern thrusters.

No Danger of Sinking

At no point was Emma Maersk in danger of sinking. Naval architects have confirmed that a fully loaded E-class vessel can sustain full flooding of the engine room and still stay afloat. Large container vessels have a natural better stability than smaller vessels. Had the incident occurred at sea, it would have been a matter of getting an oceangoing tugboat in place to assist.

Fixing the Hole

Making Emma Maersk seaworthy again is a complicated process, and Maersk Line has stated it is probably a matter of months before it can enter service again.

The first priority is to preserve the equipment, which ironically means keeping it submerged for the time being. Due to its exposure to salt water, any contact with oxygen will result in corrosion. So the plan is to have underwater welders plug the hole before lifting the vessel further, after which the remaining cargo onboard will be unloaded, water will be pumped out, and the equipment will be washed with fresh water, dismantled and retrofitted.

Uncertainties

It is still unclear whether a full dry-dock operation is needed. Even if it can be done while the vessel is waterborne, there is the question of location: is Suez suitable for the operation, or is it necessary to tow the vessel to another location? These and other questions will be determined during the coming days and weeks.

Meanwhile, the crew have been offered the opportunity to talk with a crisis psychologist, and those who wish to sign off have been allowed to do so.

Picture: The Emma Maersk was built by the A.P. Moller-Maersk-owned shipyard, Lindoe, located near Odense in Denmark (by Maersk Line).