Among other things the following factors can considerably reduce visibility.

• Gear trim angle

• Trim tab angle

• Load and load positioning

• Speed

• Rapid acceleration

• Changeover from displacement speed to planning

• Sea conditions

• Rain and thunderstorms

• Darkness and fog

• Inner lighting when under way in the dark

• Position of curtains

• People and equipment that block the helmsman’s view.

The International Regulations for Preventing Collisions at Sea (COLREG) demand that a proper lookout is kept at all times, and the “right of way" rule must be observed. It is essential that these rules are followed.