PILOTAGE PRE-PLANNING GUIDE
Leading tug: If several tug boats are involved in the towing operation there will be a
leading tug. The leading tug determines the course/power and direction of the other
tugs. When towing offshore rigs, the rig may sometimes be charged with issuing
such orders. The pilot should always be on board the leading tug.
MODU: Mobile Offshore Drilling Unit (IMO term), this term applies to most rigs
except for hotel rigs, which are designated MOU.
Towing bridle: The pennant wire which is attached to an offshore unit and to which
the leading tug attaches its towing equipment.
Figure 22. Standard towing bridle arrangement
Tow master: When towing offshore units, there will often be a tow master on board
The tow master does not necessarily have a nautical background. The tow master is
responsible for the rig when it is being towed.