DOCKING PART 3: FLYBRIDGE TWIN-SCREW DOCKING

Much has been made of Einstein’s theory of relativity, you know the one: E=mc². Now I’m sure that for someone, somewhere, this theory probably comes in handy. Personally, I can’t recall ever having used it. As far as I’m concerned the Nobel Prize should go to the guy who invented the bowthruster, or the pod system called IPS, Zeus and the like, with joystick docking. Now that’s what I call a breakthrough!

Let’s face it, if you’ve ever tried to berth a boat, stern-to into a pen, with a stiff cross-breeze blowing, you know what I’m talking about. Yachts or sportscruisers are bad enough, but a flybridge boat, with all that extra windage up top, is something else again. I wonder what Einstein would have come up with had he owned a boat and put his mind to it?

The Riviera 37 has twin Cummins B Series 330hp diesel engines with shaft drives, separate cable gearshifts (portside of helm console) and throttles (starboard of helm console).

For the purpose of this exercise you really only need to use the gearshifts. If the wind is blowing hard, you might add some extra revs with the throttles but, generally, the trick is to remain calm and avoid being heavy handed.

On our demo day there was a 15-knot breeze blowing on to our portside bow as we reversed into our berth and, to make matters worse, there was also a boat berthed in the pen next door. But before even commencing our approach it’s important that everyone aboard understands the plan of action. That way, should something go wrong during the process, one is better placed to recover.

You should also ensure that you have adequate fenders appropriately placed and at the right height relative to the dock. In this instance, as there is a cross breeze blowing, and there is another boat already in the pen next door, we’ve also placed fenders on the opposite side in case we make contact with our neighbor. Better safe than sorry!

We should also have our own lines ready and attached to the cleats on our own boat. Never rely on there being lines on the dock. Now let’s go twin-screw docking…

Step 1: 
Be aware of the wind direction and any current running. It’s good practice to keep a burgee flying off your bow so as you can quickly determine the wind direction. In terms of current, look for any sign of water running past a marina pile or marker. On the day we were out, the wind was coming from the north. This was on our stern as we travelled down the fairway towards our berth and then on hitting our port side as we reversed in.

Step 2: 
Commence your approach travelling down the fairway at idle speed and when the vessel is travelling in a straight line, you can assume the rudder is centred or amidships. At this point, you can let go the wheel and use only the engines to steer. If you want to turn to port, disengage the port engine and leave starboard engaged. This causes the vessel to gently swing to port. To go to starboard it’s the opposite gearshift setting.

Step 3: 
Any breeze will soon push the bow downwind. With the breeze coming from behind, as it is here, it is just a matter of gently engaging and disengaging our engines to maintain your course. The wind will give you some forward momentum and, as you are using the engines to steer and not relying on the rudder, there is no need for speed or extra revs.

Step 4: 
Once you are abeam of your berth, place the port engine in reverse and starboard engine in neutral. This has the effect of slowing down your forward momentum and the stern will move to starboard while our bow will start to gently swing to port. As the forward momentum is washed off, the boat will slowly move astern and in a gentle arc to starboard. The object is to have our stern facing the pen.

Step 5: 
As you continue moving astern in an arc, the bow is now pushing against the breeze and you are getting close to the entrance of the pen. So you need to increase your rate of turn. To do this we engage the starboard engine forward, while leaving the port engine in reverse. This has the effect of stopping our vessel from going astern and causes the boat to gently ‘spin’ anticlockwise, on the spot, which also brings your bow up into the breeze.

Step 6: 
As propellers are more efficient going forward than they are going astern, the propeller that is driving forward (in this case starboard) will cause the vessel to move slightly forward as it gently spins. To counteract this you can gently ‘work’ your levers, engaging and disengaging them, to maintain your gentle spin without moving too far from where you want to be.

Step 7: 
Once positioned with your stern facing into the berth, you can move both levers into reverse. This will cause the boat to go directly astern. As soon as you have momentum, disengage your engines, reengaging either, or both, only occasionally, and briefly, to keep your vessel moving in the right direction. Note: we have positioned ourselves slightly upwind of the finger with our bow slightly into the breeze, allowing for the fact that the wind will push us across and our bow around on to the finger, as we gently move astern.
TIP: 
It is vitally important when manoeuvring in tight situations that you, the skipper, look directly to the point at which you want to end up. If you look elsewhere, such as the vessel next door, Murphy’s Law says that’s likely where you’ll end up.

Step 8: 
Once you have reached the back of the pen, take your pre-prepared line and cast it over the cleat on the dock and tie off back to your boat. On a flybridge boat, it’s easier if you have someone on board or a dockmaster to assist with this, but even singlehanded this can be done calmly and without rushing around. In this instance, the breeze has gently pushed us on to the finger. However, if this were not the case and you need to bring our bow back in, you could engage the port engine (forward) and that would cause the boat to spring off the stern line and come alongside the finger.

Step 9: 
Once alongside, with the port engine in neutral, engage the starboard engine (see footnote below). This causes the vessel to spring off the stern line and be held firmly against the dock. The stern spring will stop you from going farther forward. Now attach a line from the mid-cleat on the boat going forward to a cleat on the dock to stop the vessel moving backwards. All that remains is to attach a bowline to stop your bow from drifting out. The boat is now secured, fore and aft, and it is safe to switch off your engines.

And there you have it. Berthing a twin-screw flybridge boat, stern to into a pen, with a cross-breeze blowing. Now all you need to do is practice, practice and practice some more. And no need for thrusters or pod drives. The Einstein here is the well-practiced skipper.

Footnote: 
Until the docking process is completed, you should never leave a boat in gear when guests are boarding or disembarking the boat. And only those crew operating under direction of the skipper should be performing docking tasks.