Practice question

When crossing a TSS, what angle should a vessel aim for?

  1. At a 45-degree angle
  2. At a 90-degree angle
  3. At a 30-degree angle
  4. In a straight line

Answer: B — At a 90-degree angle

When crossing a Traffic Separation Scheme (TSS), a vessel should aim for a 90-degree angle. This approach is crucial because it minimizes the time spent in the TSS and reduces the risk of collision with vessels that are following the traffic pattern. Additionally, crossing at a right angle allows for quicker and safer transit while maintaining the flow of maritime traffic in the designated lanes. Choosing an angle that is not perpendicular, such as 30 degrees or 45 degrees, could extend the duration in the TSS unnecessarily and create confusion or increase the likelihood of encountering vessels operating within that lane. A straight line crossing may imply continued navigation within the TSS without the clear intention to cross, which does not adhere to safe navigation practices and may lead to dangerous situations for all vessels involved. Thus, crossing at a 90-degree angle is the best practice for safety and efficiency in a TSS.

Practice more: COLREGs Rules of the Road Practice Test →