🔍 Key Concepts

• Behavior of a semisubmersible’s underwater profile when trimmed by bow vs. stern • How a towing bridle affects yawing/veering of a tow • Practicality and safety of using anchors or chain while underway

💭 Think About

• Visualize the rig from above: what changes if one part of the structure has more draft than another while being pulled? • Think about how having two legs of a tow (a bridle) instead of a single line can help control heading. What does changing their geometry do? • Ask yourself which option can be adjusted continuously and safely while already under tow in open water.

✅ Before You Answer

• Eliminate any choice that would normally involve risk of fouling or damage while towing at sea • Compare which options change the hydrodynamic tracking stability versus those that mainly change vertical loading • Consider which adjustment the towing vessel’s crew can make most easily in real time to reduce side-to-side veering.