To tow a vessel and keep seas to the bow or stern, the tow line should be set at which angular range?

• A. 0-15 degrees
• B. 15-30 degrees
• C. 60-75 degrees
• D. 30-45 degrees either side of dead ahead or dead astern

Answer: (D)

The main idea is choosing a tow line angle that keeps the waves hitting the bow or stern rather than the beam, so the tow stays stable and controllable. Setting the tow line about 30 to 45 degrees off dead ahead or dead astern provides the best balance: it avoids the line riding directly into the bow wave or stern wave, which would create heavy impact loads, while not pulling the tow vessel so far to the side that yaw and side loading become excessive. This angle keeps the towing arrangement aligned with the sea state enough to maintain a steady pull, minimize line strain, and reduce the risk of the towed vessel broaching or losing direction. Angles too close to straight ahead or astern can increase pounding and control issues, while angles far to the side (nearly abeam) tend to displace the tow and worsen yaw and line stresses.