How bad can it really be?

There's a question which has been asked a countless number of times, in many variations. Someone may ask "I'm looking to buy Boat X, but I don't feel ready for such a big boat without a thruster. How much do I need to budget to get one installed?" Someone else might say "I'm trying to choose between boats X and Y. Boat X is superior in almost every respect, but I really like that Boat Y has two engines, especially with regards to maneuverability. What's your advice?" I know this situation very well, because it appeared to me when I bought Nemi a few years ago. I asked the question in it's purest form: "How bad can it really be to maneuver a large single-shaft boat with no thrusters anywhere?"

As I soon discovered, there are as many ways of answering this question as there are of asking it, and the answers I got varied wildly. The most optimistic (people selling such boats) told me I wouldn't feel a thing, while the most pessimistic (people proud of ther new, huge 30-footer) told me in no uncertain terms that such activities were best left to grizzled old men with a lifetime of experience. In the end I listened to the poorly repressed optimist in my heart, and went for it. It has been an immensely valuable learning experience, maybe even enough so to justify the rather sad story Nemi has turned into.

You probably know most of the clichés by now, especially if you found this through Google. They're slow to react. They punish you severly for small mistakes. You must learn to think ahead. Yada yada. I'll cut all of that crap, and instead concentrate on the stuff I found out after I actually started using Nemi, which is hopefully the same stuff you haven't aready been told.

The first thing I learned is something I might have known on a subconscious level for years, but never thought enough about: When maneuvering at close quarters, it is more important to know what the boat cannot do, than what it can. If you figure that out, you can steer clear of any situation requiring an impossible maneuver to resolve. However, while this may be a simple concept, the details of the matter are rather complex. Most boaters of any experience will know that getting into a corner is a bad thing, but there is more to it than that. Initially I was highly skeptical about the boat's capacity to turn in confined spaces, and left myself a huge margin in every situation.

Having undertaken some maneuverability trials in open waters and learning more techniques for warping her around when there simply wasn't space to turn, I gradually gained the confidence to get into tighter spots. My experience with smaller single shafters was certainly a help, but there is a lot you won't learn if you don't have to. In other words, if it is at all possible to man-handle your craft when you need to, you will tend to allow the potential for such a need to develop. With Nemi weighing in at 35 metric tons, I didn't need telling that I must avoid those situations. Thus, there are a few widely discussed traits of such boats that I knew about on an intellectual level, but for which I had absolutely no feel.

Three of those traits come together to form an importan handling aspect: First, you must consider the direction of pull from your propeller. If it turns clockwise while under way, it will pull the stern to port when in reverse. Second, while the inertia of linear movement may seem disconcerting at first, it can be a great help in making tight turns. If you set the boat moving astern at half a knot, you can add quite a bit of power ahead before the movement reverses itself, and this helps inducing rotation. Third, the rotational inertia of a large boat can be considerable. This means that if you start a turn and let the boat sit dead in the water, it will keep turning for a while before it stops.

With the aid of the above, and considering that Nemi had a clockwise propeller and very little keel, I developed the following technique: Set the rudder 35 degrees to starboard, then alternate between forward and reverse at 30-50% rpm, so that the boat picks up 0.5-1 knot in either direction. Thus it is possible to make a full 360 degree turn inside a ~25m circle (roughly 1.5 times the boat length).

Having learned this, and having maneuvered alongside the dock on a spring a few times, I no longer felt intimidated by her, and this is when the joy of driving such a sluggish beast started sinking in. In Nemi, I can go alongside in a stiff offshore breeze, then peel and eat a banana before she starts moving away from the quay. Swell from passing boats no longer threatens to lift me onto the dock. And perhaps most importantly, as a friend of mine put it: "Wow, I just can't help getting a hard-on from controlling something this big!"



Nemi under way, with me on deck and the wife driving: