Great. This is good to know. I can use that.Thanks
Hi Heiwa, thanks for getting back to me. That sounds a lot. Great. I can use that! Thanks
That’s a nice idea 
Have you taken inspiration from Elias? For the uninitiated, it’s an extremely Norwegian children’s show featuring sentient boats:
I was brewing up a detailed response, but the question has been comprehensively answered by now. I have a few things to add, though:
Life boats are extremely docile due to their minimal engines. This will probably not be noticed by most of the people here, because ships are even slower to react to input, but it catches weekend boaters by surprise. A typical beginner’s mistake would be to approach the dock with too much way on and running out of room to slow down. Life boats have pathetic bollard pull, and while I haven’t actually tried using one to tow a flotilla of inflated life rafts on a stormy day, I suspect it hasn’t been tried anywhere outside of some bureaucrat’s mind. I’d be delighted if someone could pose references to such an attempt, because I’m sure it would be entertainingly horrifying.
Go-fast boats suffer from the opposite problem. Given the very high propeller pitch and typical absence of trolling valves, they have a single engine idle speed somewhere close to the planing threshold. They can be extremely violent when maneuvering, and it takes considerable seat time to achieve elegant close quarters handling.
Life boat handling characteristics are defined mostly by the flat bottom. This doesn’t pose any problems on a calm day, but can make it difficult to keep a course under rougher conditions. They react to wind by drifting off sideways, which can be disconcerting to someone used to gauge wind pressure by the amount of weather helm. They also slew more out of a turn, but this is something you get used to very quickly.
On the other hand, “cigarette boats” have an extreme tendency to point their bows downwind. It’s like an unladen 40m self-propelled barge, only far worse. The typically small drive center offset exacerbates this issue, to the point that many owners rely heavily on thrusters.
Life boats make excellent day boats, contrary to popular opinion. I’ve seen a number of conversions and been involved in a few myself. You cut the deck off, fair the edge, install a water cooled engine of approximately twice the power of the air cooled original (say 20-25 hp for a 28 footer) and add a propeller to match. The crowning touch is plenty of refrigeration capacity, because these boats shine when you have a happy crowd on board. Some people add storage lockers, sound systems, awnings and even pilot houses, but that’s all optional.
This rhymes with neither my experience nor my understanding of the subject. I can think of at least a few tunnel ruddered boats with strong prop walk. What does cut it down massively is a flat bottom, and I suspect that is what’s being observed.
I guess y’all are right that tunnel rudders have weak off-power performance, but I never really noticed. I think it’s because small craft handling follows a different paradigm from ship handling, with less emphasis on maintaining steerage way, and more on slowing down and using power to achieve tight turns. What is very noticeable with tunnel rudders is the improved thrust vectoring, which is similar to that of twin rudders.
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Another issue with jet drives apart from no control without trust is that they get fouled very easily. The one work boat we had with dual jet drives had a feature that reversed the flow direction to expel debris. IIRC, they were Hamilton drives and parts were difficult to get.
My only experience handling lifeboats was boats with conventional prop / rudder setup.
If a boat has heading control when going astern than the ability to maintain steerageway at low speeds in neutral is far less important.
