BOTH INTERNATIONAL & INLAND What is the minimum length of a power-driven vessel that must show forward and after masthead lights?

Correct Answer: Option B — 50 meters

Rule 23(a)(ii) dictates that a power-driven vessel of 50 meters or more in length must exhibit a second masthead light abaft of and higher than the forward one. Vessels under 50 meters are only required to show one masthead light, though they may optionally show a second.