An alert to inform interested parties about an incident in which a general cargo vessel was preparing to get underway and head to sea after loading cargo in a port on a river.
The pilot boarded the vessel and went to the bridge where the master-pilot exchange began. The vessel and master had been in and out of this port several times, so this was viewed as a routine transit. Still, the master and pilot discussed the status of the main engine, steering, and control systems all of which were operating in excellent condition.
The master shared the pilot card with the pilot who noted that the vessel characteristics were all as expected and that the vessel was trimmed by the stern. The pilot told the master that the weather was forecast to remain favourable and that other marine traffic would be minimal. They discussed the intended route for the outbound transit.
The pilot noted that there was dredging activity in the port but it primarily impacted inbound traffic and was not expected be a concern for them. With everything ready, the departure seemed routine as the vessel got underway. Harbor tugs moved the vessel away from the dock and turned the vessel to head downriver. Shortly thereafter, the tugs were dismissed and the vessel increased speed.
Everything seemed routine. The pilot was communicating via radio with a pilot on an inbound tanker. The pilot on the general cargo vessel agreed to increase speed and proceed through a bend in the river so the vessels would not pass in the bend. To do so, he ordered the vessel’s engine power to full ahead to best navigate in the river’s current and get the vessel beyond the bend more quickly. A few seconds later, the helmsman stated that the rudder was not responding normally. The entire bridge team felt the vessel shudder as well.
Shortly afterwards, the vessel quickly sheered to starboard where it crossed out of the channel and grounded. During the investigation, it was discovered that the vessel experienced an increase in draft due to squat when the engine was ordered to full speed ahead. With less than 1 foot (0.3 meters) of underkeel clearance, the stern of the vessel touched bottom and the hydrodynamic effect resulted in the loss of steering control and the vessel taking a sudden sheer to starboard.
The investigation revealed that the master and pilot had not discussed the underkeel clearance in their pilot-master exchange. The master had assumed that the depth shown on the Electronic Chart Display Information System (ECDIS) was correct and that depth had been used in preparing the passage plan. The master believed the vessel would be in compliance with the company requirement for a minimum underkeel clearance of 2 feet (0.6 meters) so he did not discussit with the pilot.
The pilot was aware of some shoaling in the river that reduced the available depth in the channel, but assumed the master was also aware of it as it had been mentioned in a published port notice the previous day. Thus, the actual underkeel clearance was never discussed. Instead of the company-required minimum for 2 feet (0.6 meters) under the keel and room for any squat, the vessel actually had less than 1 foot (0.3 meters) of clearance under the keel.
Actual Damage
The vessel sustained damage to the hull on the starboard side forward. The vessel had to be drydocked for repairs and the claim for repairs exceeded $130K.
Potential Damages
The grounding had the potential for significant claims. Fortunately, there was no damage to the propeller or rudder. They were also fortunate that when the vessel suddenly sheered to starboard, it stayed clear of port structures and other vessel traffic.
Prevention
A good master-pilot exchange includes discussing information related to every navigational aspect of the vessel and discussing details of the planned voyage into or out of the port.
- Was a checklist used for the master-pilot exchange and was it completed?
- Was the vessel’s handling characteristics discussed related to the vessel’s loaded condition and trim?
- Was all other port activity discussed including inbound and outbound vessels, construction activity, dredging, and any special events?
- Were the currents discussed including the river current, tides and tidal current, and winds?
- Was the specific use of tugs discussed including at what point they would be released?
- Were the details of the passage plan discussed?
- Was the readiness of the anchors discussed?
- Was the underkeel clearance discussed including company minimums and actual channel depth available?
When you identify a hazard before something goes wrong… it’s a Good Catch.
When you stop an operation before something bad happens… it’s a Good Catch.
When the master pilot exchange includes discussion of the
available underkeel clearance related to company policy… that’s a Good Catch, too!