Mastering The Art Of Docking Your Twin Screw Boat

Docking a twin-screw boat can be nerve-wracking, especially with onlookers, but with the right knowledge and practice, it can be done with ease. The first thing to remember is to stay calm and avoid hasty control actions. It's also important to understand the basic principles of twin-engine boat control. One key principle is to only use shifters and throttles, never the steering wheel, for idle speed handling. This is because rudders are ineffective at slow speeds. By practising using only the shifters and throttles, boat owners can develop absolute control of their vessel.

Prepare for docking by deploying fenders and lines, and checking wind and current

Preparing for docking is a crucial step in the docking process. It involves several key steps, including deploying fenders and lines, and checking wind and current conditions.

Firstly, it is essential to equip your boat with fenders, also known as "bumpers". Fenders act as a protective barrier between your boat and the dock, preventing potential damage to the hull. The type of fender you use will depend on the docking scenario and the size of your boat. For small boats, vinyl fenders are a versatile and cost-effective option. Foam fenders are suitable for larger vessels or tight spaces, while inflatable fenders are ideal for long-distance travellers due to their lightweight and compact design. When deploying fenders, consider the height and adjust accordingly. It is generally recommended to have two to four fenders per side, depending on the length of your boat.

The next step is to prepare your dock lines, also known as mooring lines. These lines are essential for securing your boat to the dock. The bow line and stern line are the most commonly used in docking scenarios. When tying a line to a fender, a bowline knot is a strong and secure option. For tying the fender line to your boat, the clove hitch is ideal as it allows for last-minute adjustments. Remember to never use any body part to slow down or stop the boat; always rely on your dock lines and fenders.

In addition to deploying fenders and lines, it is crucial to check the wind and current conditions before docking. Assess the direction and strength of the wind and current, as they can significantly impact your boat's movement and control. If possible, approach the dock against the wind or current, giving you better control over your speed and direction. This will enable you to slow down more easily and make any necessary adjustments.

By following these preparation steps and staying mindful of wind and current conditions, you can ensure a safe and controlled docking experience.

Trim engines so propwash goes under the boat

Trimming the engines on a twin-screw boat is a crucial step in the docking process. Here's a detailed guide on how to do it effectively:

Trimming the engines involves making a slight upward adjustment to ensure that the propwash, or the turbulent water created by the propellers, goes under the boat rather than hitting the transom. This maximises the effect of the propwash, making the boat more responsive to your controls. It's important to note that if you don't trim the engines, the propwash may hit the transom, making the boat harder to manoeuvre.

To trim the engines, locate the tilt-trim switch at the throttle and adjust it accordingly. This will ensure that the propwash is directed under the boat, giving you greater control. By trimming the engines, you can take advantage of the increased propeller blade area and "bite" on the water that twin-engine boats offer, making docking easier.

Remember to prepare for the docking manoeuvre by deploying fenders and lines, and always be mindful of wind and current conditions to avoid any surprises. These factors can impact the effectiveness of trimming your engines, so it's crucial to take them into account.

Additionally, communication is key during the docking process. Ensure that everyone on board and any dockhands are aware of the plan and their roles. Clear and concise communication will contribute to a smooth and safe docking experience.

By following these instructions and staying calm, you'll be able to successfully trim your twin-screw boat's engines and maximise the effect of the propwash for a controlled and efficient docking procedure.

Approach the slip at a 90-degree angle, then centre the steering wheel

Approaching the slip at a 90-degree angle is a straightforward method that can be used even by inexperienced boaters. When the middle of your boat is aligned with the middle of the slip, stop and centre your steering wheel. Centring the steering wheel is crucial as it ensures that you can now turn the boat more easily by opposing the engines. This means shifting one engine into forward and the other into reverse, causing the boat to spin.

It is important to resist the temptation to touch the steering wheel and instead rely solely on the engines for this manoeuvre. By opposing the engines, you can get the boat spinning in the desired direction. Remember that the bow will move in the direction of the throttle you shift into reverse. For example, shifting the starboard throttle into forward and the port throttle into reverse will cause the bow to spin to port.

In an ideal scenario, you would have no wind or current, and ample space to manoeuvre. In this case, simply spin the boat until it is perfectly parallel with the finger pier. From there, it is a simple matter of shifting both engines into reverse idle and backing up gently into the slip.

However, it is more likely that you will encounter some constraints, such as limited space, which will require you to continue manoeuvring the boat as you back up. If you cannot spin the boat completely due to space constraints, you can remove all forward thrust by taking the forward throttle out of gear. This will cause the boat to start backing up while still spinning, allowing you to get closer to the slip.

As you continue to back into the slip, make adjustments as needed. If you need to stop the spinning motion, briefly reverse both throttles. If the bow is not aligned correctly, make light adjustments by shifting starboard reverse or port forward to bring it alongside.

Oppose the engines to spin the boat

Opposing the engines to spin the boat is a key technique when docking a twin-screw boat. Here's how to do it:

Firstly, it's important to prepare for the docking manoeuvre by deploying fenders and lines, and checking for wind and current conditions. You should also trim your engines slightly upwards to ensure the propwash goes under the boat, making it more responsive to your controls. As you approach the dock, stop with the middle of the boat aligned with the middle of the slip and centre your steering wheel.

Now, to spin the boat, you put one engine into forward and the other into reverse. The boat will then begin to pivot on its axis. The direction of spin depends on which engine you put into forward and which into reverse. For example, if you shift the starboard engine into forward and the port engine into reverse, the bow will spin to port. You can control the speed and radius of the turn by adjusting the throttle on each engine.

If you need to fit into a tight space, you can remove all forward thrust by taking the forward throttle out of gear once the boat has begun to turn. This will cause the boat to start backing up as it continues to spin, allowing you to get closer to the dock. You can adjust the rate of spin by shifting in and out of gear. As you get into position, you can stop the spin by briefly reversing both throttles, then back slowly into the dock.

Opposing the engines to spin is a useful technique, but it can be tricky to master. It's important to practice in a safe, open area before attempting to dock in a crowded marina. Remember to stay calm and make small adjustments if the wind or current starts to push you off course. If you do make a mistake, there's no shame in pulling away and starting over.

Shift gears to straighten the boat and reverse into the slip

Shifting gears is an essential technique to master when docking a twin-engine boat. Here's how to straighten the boat and reverse into the slip:

Understanding the Basics

Before attempting to dock, it is crucial to understand the basic principles of twin-engine boat control. At idle speed, the rudders have minimal impact on steering, so you must rely primarily on the shifters and throttles for manoeuvring. Practice using only the shifters and throttles to control the boat's movement. Get a feel for how the boat behaves when one engine is in forward and the other in reverse, as well as when varying the throttle speed on each engine. This will help you develop a sense of how to use the controls to make sharp turns and control the boat's rotation.

Shifting Gears to Straighten the Boat

When approaching the slip at a 90-degree angle, stop once the middle of your boat is aligned with the middle of the slip. Centre your steering wheel and prepare to shift gears to straighten the boat. To do this, shift one engine into forward and the other into reverse. Remember, the bow will move in the direction of the throttle shifted into reverse. For example, if you shift the starboard throttle into forward and the port throttle into reverse, the bow will spin to port.

Managing Constraints

In reality, you may encounter space constraints that prevent you from spinning the boat completely. In such cases, you can remove all forward thrust by taking the forward throttle out of gear, allowing the boat to start backing up while continuing to spin. Adjust the throttles to find the right balance between backing up and spinning. As the boat moves into the slip, you can briefly reverse both throttles to stop the spinning motion and then back slowly into the slip.

Dealing with Wind and Current

Before initiating the docking manoeuvre, always check for wind and current. Be prepared to adjust your approach and control inputs accordingly. If a strong gust of wind or a misjudgement of the current affects your alignment, use your judgement to apply more or less power to one engine or the other to correct your course. If necessary, don't hesitate to pull away from the slip and start over.

Frequently asked questions