Question 358Navigation General

The correct answer is B) One long blast followed by one short blast. According to the U.S. Coast Guard Navigation Rules, when approaching a lock and at a distance of not more than a mile, vessels desiring a single lockage shall sound one long blast followed by one short blast as the signal. This indicates to the lock operator that the vessel is requesting a single lockage. The other options are incorrect because they do not match the standard signal prescribed in the Navigation Rules for this situation. Two short blasts, one short blast followed by one long blast, and two long blasts are used for different purposes and would not be the appropriate signal when approaching a lock.