Which whistle signal indicates a vessel backing astern propulsion?

Which whistle signal indicates a vessel backing astern propulsion?

• A. One long blast
• B. Three short blasts
• C. Two short blasts
• D. One short blast

Answer: (B)

Three short blasts is the standard whistle signal for a vessel backing astern propulsion. In the collision avoidance signaling used at sea, reversing the engine is communicated by a rapid sequence of three short blasts, signaling to nearby vessels that you are moving backward and may have limited steering or stopping capability. This specific, distinct pattern helps others understand your immediate maneuver and adjust accordingly to avoid a collision. The other options aren’t used to indicate backing; a single long blast, two short blasts, or a single short blast are assigned to different movements or warnings in the signaling scheme and do not convey the action of reversing propulsion.

Three short blasts is the standard whistle signal for a vessel backing astern propulsion. In the collision avoidance signaling used at sea, reversing the engine is communicated by a rapid sequence of three short blasts, signaling to nearby vessels that you are moving backward and may have limited steering or stopping capability. This specific, distinct pattern helps others understand your immediate maneuver and adjust accordingly to avoid a collision.

The other options aren’t used to indicate backing; a single long blast, two short blasts, or a single short blast are assigned to different movements or warnings in the signaling scheme and do not convey the action of reversing propulsion.