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If Another Boat Signals Their Intention To Pass You From Astern What Should You Do?

Fact checked by William Hart

if another boat signals their intention to pass you from astern what should you do

If another boat signals their intention to pass you from astern what should you do?

This is among the most asked questions when it comes to safe commuting on the water. The answer depends on where the other vessel is coming from.

In most situations, the boat operator will use a horn to signify you – one blast means they’re coming from the right side (starboard), and one tow blast means they’re coming from the left side (port).

For more details about the waterway rules, see today’s article.

Table of Contents

Actions to Take When Signated to be Overtaken

1. Respond To The Signals


It is mandatory for a skipper to follow a course of action to prevent collision with another vessel when the boat passes from behind them.

Boats of all sizes are required to have an efficient sound-producing device. Since the federal law didn’t mention anything specific regarding the type of device, you can choose one to your liking, but make sure it’s a reliable one.

  • Boats that are under 39.4’ in length – The skipper can utilize a whistle, a bell, or an air horn.
  • Boats that are above 39.4’ in length but under 65.6’ — The skipper must use both a bell and a whistle. In this situation, the whistle is required to be well-operated for half a mile in nautical measurements, while the bell is required to have a minimum diameter of 7.87”.

Below are the sound signals for boats used to communicate changes in directions.

  • 1 short blast means the other vessel wants to surpass you from their port.
  • 2 short blasts mean the other vessel wants to surpass you from their starboard.
  • 3 short blasts mean the other vessel is operating astern propulsion.

After receiving sound signals from the overtaking vessel, your job is to give a reciprocated answer.

If the overtaking vessel lets out one short blast, you should also let out one to give agreement. Respond likewise if two short blasts from a vessel are let out, and there’s no risk indicated. However, if you don’t accept their passing signal, respond with five rapid blasts or more to imply danger.

Besides overtaking, there are also crossing and meeting situations.

  • Crossing situation – A crossing situation takes place when you and another boat are crossing the same path. In this situation, the vessel coming from the starboard side has the right to keep on its course as a stand-on vessel, and the other boat would become the give-way vessel.

Nonetheless, if it is apparent that the give-way vessel is not responding in time, the stand-on vessel ought to take evasive action to prevent a collision.

  • Meeting situation – A meeting situation happens when you’re approaching another boat head-on. What you’d want to do is to steer to the right, if possible, to give space for the oncoming vessel, and they would do likewise.

2. Maintain Course And Speed


After agreeing to be overtaken, the skipper of the vessel being overtaken shall hold its course and speed. Reducing or speeding in this situation would pose a risk of collision.

3. Be Aware Of Your Surroundings


Rule 5 of COLREGs indicates that you must always maintain a proper lookout of the surroundings by sight and hearing to identify risks of collision in the prevailing conditions.


If another boat signals their intention to pass you from astern what should you do?

By now, you should know the boating rules as regards this question. Whether you agree to let them pass or not, you’re always accountable for responding to passing boats with signals correspondingly.

Besides, both vessels should always be prepared to take proper action to avoid collision in case of confusion or ignorance of the rules on the part of the other boat operator.

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