Approaching fuel dock with twin screw boat

Recently, actually last May, went from single screw sailboat to twin screw power boat. With the sailboat we would approach the fuel dock on the port side, come in at a slight angle and when the bow was in position, put the engine in reverse and propwalk would pull the rest of the boat against the pilings.

After spending much time on upgrades and maintenance we are ready to head out for the first time, not counting bringing the boat home. So what is the proper procedure for getting alongside a fuel dock with twin screws?

Bob

BobH said:

Recently, actually last May, went from single screw sailboat to twin screw power boat. With the sailboat we would approach the fuel dock on the port side, come in at a slight angle and when the bow was in position, put the engine in reverse and propwalk would pull the rest of the boat against the pilings.

After spending much time on upgrades and maintenance we are ready to head out for the first time, not counting bringing the boat home. So what is the proper procedure for getting alongside a fuel dock with twin screws?

Bob

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Bob, first off port or starboard may depend on the side your fuel tank is on or more importantly IMO, the direction of the wind and/or current. There are a lot of instructional videos on this on U Tube, just seach docking twin screw boat and you will see lots.

Throw a cushion in the water and pretend it is a dock or a person. Practice practice.

Here is how I was shown. It works. All this assumes you have counter rotating props which most twins have. First off, centre the wheel when close to the dock. Now let's consider the shift levers. This could be difficult to describe in writing. Look at the shifting as two C's, one backwards like this:
(I I) with the I's being the levers. The left hand set obviously represents the port lever. With the starboard lever in neutral placing the port lever in forward will drive the boat's bow to starboard and conversely placing it in reverse will drive the boat's stern to starboard. Obviously the opposite with the port in neutral and operating the starboard lever. In and out of gear in small blips and drift her in. The trick is to imagine that the C's have an arrow head on each end. Unless you get in a real mess you shouldn't have to touch the wheel. If you must, use the wheel to get back out of trouble and start over. Better to abandon a bad approach than try to rescue one. And another thing, don't worry about what people on the dock might think.

I will add:

DO NOT throw any lines to anyone on the dock unless you are ready to give up control of your boat!!!! You may already know that but your guests aboard may not and can't resist the urge to throw a line to someone so willing to "help". Make sure you brief your guests/crew on this or they will do exactly what I am saying.

Sorry I can't add to twin engine boat handling as I have never owned one!!!...looking forward to it though.

Approach the dock at an angle of around 30degrees with rudder centered & both engines at slow idle. Do not touch rudder once centred. If intending to put the stbd side to the dock, leave Stbd engine in idle fwd to maintain some fwd momentum & a couple of yards off the dock, put Port engine into reverse. This will pull the stern into the dock. You can reverse as hard as necessary to arrest momentum and bring the vessell parallel to the dock, then pull both engines into neutral. (If intending to put Port side to dock, leave Port engine in idle fwd and put Std engine into reverse).

Actually the same procedure as the sailboat works pretty well..just reverse your outboard engine.

As one who is contemplating a move to a vessel equipped with twins, I had the same question.

I guess for me a fundamental question is stern propwalk in reverse.

Understanding that twins usually have counter rotating props, are they generally set up the same way, i.e., the port is clockwise and the starboard is counterclockwise (or vice versa) when going forward?

That brings up my question, assuming that there is a standard convention for the clockwise/counterclockwise arrangement: if when coming into a dock on your port side, if you leave your starboard engine in neutral and put your port engine in reverse, will the stern walk to port?

if you leave your starboard engine in neutral and put your port engine in reverse, will the stern walk to port?

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No, to starboard.

We use the same procedure for approaching any dock, port or starboard side. We angle in toward the dock at an angle of about 30 to 45 degrees depending on how much space is available or if there is a boat directly behind where we want to be. We "aim" the boat so that the bow would contact the dock about 3/4 of our boat length beyond where we want the stern to end up.

When the bow is just a few feet--- 3 or 4--- from the dock we put the outside prop in reverse and the inside prop in neutral and the wheel hard over away from the dock. A shot of power (I didn't use to do this but now I do) on the reversed prop engine both stops the boat and starts the stern swinging into the dock. As soon as the boat's forward motion stops we put the inside prop in forward.

At that point the combined prop walk of both props toward the dock and the thrust from the inside prop against the hard-over rudder behind it moves the boat in quite smartly against the dock. We have four-bladed props so there is a lot of propwalk, which is very beneficial to have in this situation.

The fact we did not start this maneuver until the bow was virtually at the dock means the boat ends up nicely parallel to the dock with the aft end up against it, and whoever is not driving can step to the dock with the aft-running spring line and fasten it off. With the spring fastened off the helmsman can then pin the boat against the dock against the line if the current or wind is trying to move the boat off the dock.

We use this procedure in every docking situation we encounter, including our own slip which we enter on a curve past the stern of the sailboat we share the slip with.

If the wind or current off the dock is strong we still use this procedure. The only difference is the speed with which we do it and the amount of power we use to yaw the back of the boat into the dock and the hustle in the person getting the aft-running spring ashore and fastened off.

We found that this technique--- which is used by all the experienced boaters we know like Carey of this forum--- came quite naturally to us because it's the same approach and stop technique we use in floatplanes. Of course with them there is no differential thrust or reverse (unless it's a turbine) and the aft-running spring is me or my wife on the dock pulling back on a line permanently attached to the float strut, but the basic approach judgment is exactly the same.

Shut off one engine. Come in as usual.

Take a look at these instructional vidios:

How to Dock Your Twin Inboard Boat | BoatTEST.com

Thanks for all the replies. I guess I didn't think this through, in the back of my mind I guess I considered propwalk a sailboat problem/feature. Now I realize that with two props there is probably twice the propwalk.

Thanks again, now I can't wait to fill those huge diesel tanks.

Bob

Baker said:

I will add:

DO NOT throw any lines to anyone on the dock unless you are ready to give up control of your boat!!!! You may already know that but your guests aboard may not and can't resist the urge to throw a line to someone so willing to "help". Make sure you brief your guests/crew on this or they will do exactly what I am saying.

Sorry I can't add to twin engine boat handling as I have never owned one!!!...looking forward to it though.

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That is the voice of experience. There is nothing like trying to come in along side, and someone ties your bow line short.

John's right. Tell your crew to not put a line ashore until you tell them. No matter how someone maybe saying, "throw me a line".

BobH said:

Thanks for all the replies. I guess I didn't think this through, in the back of my mind I guess I considered propwalk a sailboat problem/feature. Now I realize that with two props there is probably twice the propwalk.Bob

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Most times, when both engines are doing the same thing, they cancel each other out.
If you just use the non dockside engine, as Alomaria suggests, do what you`ve done before, that will get you alongside and fueled. In a little while you can be using 2 engines too, with the info others posted and your own research and experience.

A very simple and straightforward way to understand the effect shift levers have on your boat, picture you with your hands on the handle of a shopping cart.

If you want to make a gentle turn to the port (for example) you might hold steady with your left hand and push forward with your right hand. Same thing on the shifters.

If you want to make a quick turn (or a U-turn) to the left with your cart you'd pull backward with the left hand and push forward with the right hand. Same thing with the shifters.

I always do four things when I'm coming into a situation where I am going to be maneuvering at very slow speed...
1. Center the wheel (and rudders)
2. Make sure the autopilot is turned off
3. Make sure the engine synchronizer is turned off
4. Make sure both engines are at idle

If I do those four things and keep the shopping cart example in mind, things go much easier.

Depending on the situation I've found that the rudders can be an essential component of maneuvering. To the point where I rarely have the rudders centered any more when maneuvering. Putting them over one way or the other can greatly speed the pivot of the boat, particulary against a current or wind, and enhance the accuracy of where the boat ends up.

I also used to always maneuver at dead idle. No more. I use power more and more now as an aid to positioning the boat accurately. Sometimes in forward, sometimes in reverse, usually on only one engine or the other at a time, and generally in short but sometimes fairly strong bursts. Power is particulary useful when wind or current is a factor working against us.

I've a long ways to go to learn to use power as proficiently and precisely as the commercial boat drivers I've been using as my "teachers" by observation. But it's really made the diffrerence between an uneventful docking or maneuver and a less-than-ideal one.

BobH said:

.................. After spending much time on upgrades and maintenance we are ready to head out for the first time, not counting bringing the boat home. So what is the proper procedure for getting alongside a fuel dock with twin screws?

Click to expand...

I don't see any difference between approaching a fuel dock or any other face dock (assuming the fuel dock in question is a face dock).

I have a single screw inboard and generally, I approach the dock facing into the current, then at the last minute, turn the wheel away from the dock and idle in and hit reverse to stop. At this point, my wife and I can toss lines to whoever is tending the dock.

If there's nobody there to catch the lines, my wife will step off the swim platform with a stern line and I'll toss her the bow line. If I have to, I'll use the bow thruster to swing the bow away from the dock which brings the swim platform against the dock so she can step off. This is where you can use your tin engines to do the same thing.

There are a lot of variables with wind and current so each experience will be a little different. Chapman Piloting covers these situations pretty well and would be a good read for you.