UK's Marine Accident Investigation Branch (MAIB) reports on fatal accident involving tug capsize, set out safety lessons learned
In a summary of their findings MAIB report in their 'flier':
Last August, the tugs Steven B and Chiefton were connected to a 60m crane barge in a combined push/pull configuration. Steven B was secured aft with a combination of wires and ropes, making the tug and barge a composite unit. The distance between Chiefton, which was pulling, and the barge was 8.4 metres.
There were two pilots positioned on the crane as the tow was navigated from St George Wharf towards Gravesend on the River Thames.
Chiefton’s and Steven B’s engine powers were set at 95% and 70-75% respectively as the tow approached the eastern buoys of Greenwich Ship Tier, where it was set to the south by the flooding tidal stream.
Port helm was applied by Chiefton’s skipper in an attempt to prevent the barge making contact with the northernmost buoy.
The pilot then instructed him to pull to port and ordered starboard helm on Steven B in an unsuccessful attempt to “lift” the barge to port.
The barge turned to starboard, hit the buoy and then collided with Chiefton, overrunning her and causing her to capsize and founder. The skipper and mate were rescued from the river but the engineer/deckhand, who was a non-swimmer and was not wearing a lifejacket, sadly drowned.
All those involved had wide experience of tug operations on the River Thames.
However, virtually no one engaged in either the planning or execution of the tow had experience in the specific combined push/pull configuration used on the day, with pilots involved, downriver of Tower Bridge.
No one had been formally nominated to be in overall charge. The towage plan focused on the difficult bridge transit phases and did not cover in detail the downriver tow.
The full report is available here.