A quality anchor is a sailor’s best friend.
Deployed correctly, most know it’s the secret to a good night’s sleep. It's also the only emergency hand-brake a vessel has, so understanding how to use it should be mandatory training for anyone who might be a regular crew.
General anchor system guidelines
- There are many types of anchors available. Some are better on mud and sand and not that effective on rock; some are good on rock but ineffective on any other bottom material.
- Anchors that perform well on most seafloor substrates include the CQR, Bruce and Delta.
- Anchor rode (or warp) can be all chain or a mixture of rope and chain. The chain always goes at the anchor end. The chain is an essential component of the holding power of your anchor system. Providing the winch can lift the total weight, more chain is better.
- Get professional advice from a reputable chandler when setting up an anchoring system. The weight and windage of a vessel should always be the first consideration.
- Coloured markers attached at measured intervals to the anchor rode are an excellent way to ensure anyone setting the anchor can accurately assess how much rode is deployed. See point 7 below.
General anchor deployment guidelines
- Pick your location carefully. Be mindful of damage to reefs, wrecks and watch for power cables. Find hazard information on navigation charts and most GPS units.
- If other divers are in the area, look for bubbles before dropping your anchor.
- Ideally, deploy an anchor in a well‐protected area with adequate water depth and a sandy or muddy bottom.
- Head into the wind and tide and slowly move the vessel to a point slightly ahead of ahead of the place you want the anchor to lay.
- Stop the boat and slowly lower the anchor over the bow to the bottom when in position.
- Slowly reverse the vessel, deploying anchor rode as you go.
- A general rule of thumb is to deploy at least three times as much rode as the water depth. For example, if you anchor in 10 meters, feed out 30 meters of anchor rode.
- With rode secured, gently reverse the vessel to test the quality of the anchor set. If the anchor is dragging, pull it up and start again.
- Depth of the water, wind strength and current, can affect the effectiveness of the anchor holding.
- Caution: Do not anchor your boat from the stern, as this can result in an unexpected swamping and sinking incident
Pulling the anchor up or “weighing anchor” should be relatively easy.
- If possible, move the vessel slowly forward under power, retrieving the slack rode as you go. Take care not to run over the anchor rope accidentally. Even sinking anchor rope can entangle the propellor if you travel too quickly.
- Take care not to bang it on the boat's hull as the final two or three metres of rode are retrieved.
- Stow the anchor and all the rode securely ready for its next deployment.
Jettisoning the anchor
Should for any reason you need to jettison an anchor, attach a buoy to the rope end so you may recover it later.
If possible, it is wise to tie a heavy sinker or spare dive weight three or four metres down the rode to help reduce the risk of another vessel entangling its propellor in your jettisoned anchor rode.