Contact with Grain Conveyor: Over-Reliance on Floating Navigation Aids
The National Transportation Safety Board (NTSB) has released its investigation into the October 23, 2018 incident where the towing vessel Andrew Cargill MacMillan made contact with a grain conveyor - citing an over-reliance on floating navigational aids.
The vessel was pushing 42 loaded barges southbound on the Lower Mississippi River, near Tallulah, Louisiana. While rounding a bend, the tow touched bottom, resulting in the head of the tow contacting breasting dolphins and a conveyor at the Farmers Grain Terminal at mile 442.4. The conveyor was destroyed, and the dolphins and a lead barge were damaged. There were no injuries to the 10 crew on board or anyone ashore. There was no release of pollutants. Damage was estimated at $8 million for the conveyor and dolphins and about $74,000 for the barge.
The NTSB stated that the probable cause of the contact was the pilot’s over-reliance on floating aids to navigation which resulted in the tow being out of position and sliding too deep into the bend before the terminal to recover and successfully complete the turn.
During high water and strong current conditions, as were present in the river at the time of the accident, buoys can “dive,” meaning they momentarily submerge partially or fully, thus making them difficult to see, especially with about 1,200 feet of tow in front of the wheelhouse. The pilot, who was steering the head of the tow to the buoy closest to him, momentarily lost sight of the red buoy and mistakenly steered on an object drifting in the vicinity of where he last saw the buoy. By the time the buoy had re-appeared and the pilot realized he was steering on the drifting object, the tow was in the center of the river and sliding towards the right descending bank.
The report is available here.