Towing with your Tender

As catamarans usually have twin engines, it’s less likely that you’ll ever need to tow a cat. But they can be pushed quite easily. (See Diagram 5.) It’s extremely important when pushing a cat to have the two bow push lines in good condition and well secured. The tender’s bow line acts as one of the lines. The other is attached to the same bow eye as the bow line. The lines should be attached as far aft as possible on the cat’s hulls. If one of these lines lets go when you’re pushing hard, the tender will scoot ahead under the stern deck, with a high likelihood of injury to the operator.

When pushing from astern or on the hip, if you have to stop the boat or maneuver quickly to avoid an obstacle faster than the boat’s forward momentum allows, use hard reverse and pivot the boat while the helmsman holds the rudder in opposition. The rapid turn will quickly slow and eventually stop the boat’s forward carry.

Towing Astern
Towing astern is the preferred method for longer tows, rougher conditions, or times when occasional large wakes may be encountered. This method requires the highest degree of skill, and it’s also perhaps the most dangerous if done improperly.

Good planning ahead of time with your crew is imperative, as communications won’t be as easy as they are when using the other methods. When towing, you won’t have a good line of sight to the helmsman, and the sound of the motor makes hearing difficult. Arrange some easily understood hand signals for stopping, slowing down, speeding up, change of direction, and the like. A handheld radio is helpful. Have the helmsman steer for the stern of the tender.

If the towed boat steers erratically or turns off in a different direction, it’ll cause the tender to go off course. In extreme cases, it can cause the tender to be overrun by the boat’s momentum as the tender struggles to stay in front or is swept alongside and aft, then swung stern-to as the boat surges ahead and the towline takes up.

When preparing to take the boat in tow, first rig your towing bridle. (See Diagram 6.) I clip the bridle on one transom eye, then run the line aft of the motor, securely attach my towline, then tie the bridle to the other eye. The bridle should be short enough to keep clear of the tender’s propeller but long enough to keep it clear of the motor. When the towline is centered and under load, it should form close to a 90-degree angle. I make sure that my towline is in several smaller coils and able to run free. Usually it’s best to approach the boat’s bow from leeward, then pass or toss the towline to the crew. I usually keep the bulk of the coil with me to lessen the risk of a foredeck tangle. Once the line is secure, maneuver ahead slowly and toss the remaining line astern.

As long as you’re moving forward, the line will stay clear of the tender’s propeller. As the slack comes out, ease ahead until the line grows taut. Depending on the conditions, I’d deploy 50 to 75 feet of towline to start. Gradually increase speed, and have the person on the bow adjust the towline so that the boats are in step, that is, both in the trough of the seas at the same time.

Towing out of step puts intermittent strain on the towline, as one boat surges down a wave while the other boat slows down climbing one. Having the towline properly secured is very important. If it comes loose or breaks a cleat, the loose end will slingshot toward the tender. The crew on the boat needs to keep an eye on the towline for signs of chafe and to ensure that the line remains secure.

Tugboats and purpose-built towboats are set up with towing bitts located forward of their rudders. This allows them to turn “under the tow” and maneuver. This can’t be done in a small inflatable, as the outboard motor is in the way. Attempting to tow from forward of the motor risks that the towline will catch on the motor’s cables and controls.

A technique that I’ve used when towing with boats that lack towing bitts or have outboards in the way involves using a sliding bridle. (See Diagram 7.) Anyone who’s attempted to tow a boat from off center knows that the towboat will rapidly be pulled sideways, and any attempt to get out in front means slacking the towline, trying to avoid getting it caught in the propeller, and starting over. With the sliding-bridle method, you attach the towline to a smooth stainless-steel ring or a seized shackle that can freely slide from side to side on the bridle. If one isn’t available, simply tie a bowline onto the bridle. When you first take a strain, the towline will go to center. Let’s say that you want to turn to port. Ease off on the throttle, but not so much that the line goes completely slack. Turn hard to port. As the tender’s stern goes to starboard, the towline slides to port. Take up the strain; when the tender is in the desired position and the towed boat is on the desired course, ease off, turn slightly to starboard, and throttle up to center the towline. This method served me well for many years when towing boats and floats at my boatyard.

In conclusion, I want to emphasize the importance of preparing and planning ahead for any of these maneuvers. Know the capabilities of the crew and tender, and take the time to practice. Good boathandling is a sign of good seamanship.

Captain Earl MacKenzie, who holds a 500-ton Ocean Master license for power and sail, and his wife, Bonnie, run and operate Bonnie Lynn, a U.S. Coast Guard-inspected brigantine rated for ocean service. To learn more about the MacKenzies, see “Bonnie Lynn: A Dream in Fast-Forward” (August 2000).