How to Anchor a Boat Overnight - Superyacht Edition

Dimitris Tsapis
May 8, 2021

When working on a superyacht, each and every process requires strategic planning and laser-like focus. Doing so tightens the room for error and ensures that no human mistakes are made. 

Anchoring a yacht is no different.

While the process seems rather simple to those unfamiliar with the industry, there are many variables to keep in mind. This makes anchoring a delicate process that requires excellent communication between crew and captain, especially when planning to anchor your vessel through the night.

This article will delve into the exact steps you need to follow when anchoring a boat overnight, best practises and terminology, as well as the differences between small and large yachts. Hence, if you want to learn how to anchor a boat overnight, make sure you bookmark this post for future reference.

Contents

Anchoring basics - What to take into consideration

Smaller motor yachts and luxury superyachts are not the same when it comes to anchoring. While the process has many similarities, it is important to remember that, the larger the vessel, the more people will likely be involved in the process. In small motor yachts, the captain may be able to handle the process but there should always be a second person to look over the deck to ensure the anchor is doing what it’s supposed to. For larger (super) yachts, the captain stays on the bridge while the deck officer together with a deck hand takes care of the practical work, always remaining in constant communication with the bridge.

Before we delve into the process and its steps, you need to keep some tools and terminologies that are essential for this process:

  • Anchor ball (or buoy) - A black-colored buoy placed in the front of the deck, indicating to other boats that you anchor is dropped.
  • Anchor shackle length - Universal unit of length for anchors.
  • Chain counter (or rode counter) - a tool that tracks the length of anchor chain deployed.
  • Windlass (or gypsy wheel) - A mechanical device that releases and withdraws the anchor line in the chain locker.

Finally, note that the anchoring process is never exactly the same, as there are different elements you need to keep into consideration.

  • Weather forecast and wind speed
  • Anchoring limitations in particular zones
  • The amount of chain you need to lay out
  • Different types of seabed
  • Other vessels in close proximity

All these variables further indicate the importance of experience and proper communication over theoretical knowledge. We discuss them in more detail over the next few chapters, where we explain the steps you need to follow when anchoring overnight.

Anchor shackle length

From the terms mentioned above, the anchor shackle length is the one of the most basic things to know. The length of your anchor chain is measured in “shackles”, a nautical unit that is universally known among boaters.

How long is a shackle of anchor chain?

One shackle is 27,43 meters, or 90 feet in length. When measured in meters, shackle anchor length is rounded up to 27,5 meters for convenience.

How are anchor shackles measured?

To tie this information with the anchoring process, it is important to understand how shackles are measured during the process. To indicate the length of 1 shackle of anchor chain, boats will usually have two different types of indication.

Larger boats and superyachts will usually mark the end of a shackle and the beginning of a new one by painting it red.

anchor shackle length

To make measurement even more convenient, each following shackle will have white-painted links (one by either side for each following shackle). Each consecutive shackle will have an additional white link on each side.

length of anchor shackle

This helps the crew understand the depth of the anchor if no digital equipment is used or if the chain needs to be dismantled in order to add or remove chain as needed.

Smaller boats and yachts, on the other hand, have a different colouring method to track shackle length. Instead of the red-white color combo, each shackle end point is painted in different colors.

  • 1st shackle is painted red.
  • 2nd shackle is painted yellow
  • 3rd shackle is painted blue
  • 4th shackle is painted white
  • 5th shackle is painted green.
  • If there are more shackles of chain, the colouring pattern will simply repeat.

Measuring shackles from on-deck vs water line

Another common question when it comes to shackle length is whether the starting point should be from the height of the deck level or the water line, which is lower. To answer this, it is important to take the size of the boat into consideration. When dropping anchor from a regular sized motor yacht (2-4 meters above water level) you can start counting from the height of the deck, since the difference is rather small. When you drop anchor from larger boats however (and this includes many superyachts), it is best to start the counting from the water line.

How to anchor a boat overnight

All right, having introduced the basics, it is now time to drop the anchor! 

The anchoring process starts on top of the bridge, where the captain spends most of his time. When you find a spot that seems appropriate, and yacht’s nose is facing the direction of the wind, you’ll first need to look at the depth of the water. This will help you understand how many shackles of chain will need to be released. A good rule of thumb is to maintain a ration of 5:1. 

For example, if the water has a depth of 10 meters, you’ll need to release 50 meters of anchor chain, or approximately 2 shackles. Depending then on the way your anchor is painted, you would be looking at either a red mark with two white links on each side (large vessel), or a yellow mark (smaller vessel).

Knowing how many shackles of anchor chain you’ll need to release you will now either walk to the front deck of your yacht or, if the vessel is large, start the anchoring process together with the chief deck officer.

Once on the front deck, you will find your hydraulic windlass, as well as the manual brakes. 

how to anchor a boat overnight

You can use these in combination with the chain counter to understand how many shackles of chain is released in the water. The terminology gets a little more complex on superyachts. If you want a more precise explanation of all the equipment you’ll be using, watch the following clip.

Step 1: Dropping the anchor to the water line

The first thing you want to do now is make sure that the equipment is working properly and that you take all necessary safety precautions the ensure that the vessel doesn’t get damaged. As such, as the yacht comes to a stand still, the first thing you want to do is to slowly drop the anchor at waterline. If you are using a chain counter, make sure you set it at zero in case you measure the length from waterline.

To start this process make sure that the windlass (or gypsy wheel) and the manual brake are both secure. In this case, the first thing you will do is unscrew the devil’s claw, which is the safety valve of the anchor. Next, engage the windglass by rotating it and release the break to start dropping the anchor electronically, using the control.

Step 2: Dropping the anchor freely

The brake must now be reapplied so that we can disengage the windlass from the capstand to make the anchor ready to drop freely. The disengagement of the windlass can happen either through unscrewing it with your hand (shown in video further below), or by using a tool made for the occasion.

Using the remote, we can test if the capstand is spinning freely, in which case the only thing holding the anchor is the break we reapplied earlier. By releasing the break, the anchor will start dropping, which will cause an aggressive release of chain until the anchor hits the bottom. After that point, the chain will release slower until the desired anchor shackle length is reached. The break is reapplied as soon as the desired color of shackle length is seen by the person releasing the chain.

Step 3: Securing the vessel

As soon as the deck informs the bridge that the desired anchor length is reached, the captain can now proceed to secure the vessel. This is either done by allowing the yacht to move back (since it’s facing the wind) or even include a little bit of reverse engine power to make sure the boat doesn’t move. The engines can now be switched off and the windlass can be locked into position.

Since the chain to depth ratio is 5:1, it is important to calculate your surroundings. This is especially important when you first learn how to anchor a boat overnight.

  • First off, it’s time to put up the anchor ball. When anchored, it is mandatory to display one black ball of 60cm diameter to warn passing vessels about the length of anchor in front of your vessel. Since other boats are also able to track the depth, the will know your approximate anchor position, and avoid risky movement.
  • When anchoring overnight, vessels under 50 meters will require one all-around white light. Vessels over 50 meters will require two all-around white lights, which are always visible from all directions and protect you in terms of insurance.
  • Another thing you need to keep in mind when learning how to anchor a boat overnight is the position of your surroundings. Allow swing room (based on shackle length) in case the direction of wind changed during the night. The position of each vessel should be in direct proportion to the depth of the water, the position of the anchor, and the direction of the wind.

Anchoring overnight - Putting it all together

Closing, we found a great video that outlines the process you should follow when anchoring a superyacht. Make sure you watch it to better comprehend all the things you learned from this blog post.


You should now how to anchor a boat overnight, and the steps you need to follow to ensure your (and your vessel’s) safety. When anchoring overnight, make sure to always have at least one person awake and aware of the surroundings and don’t forget to place the anchor ball and lights to help other become aware of your position.