Boat handling with twin engines

I beg to disagree re.outdrives.
With outdrives, it's not just a matter of faster manuevering, there are actually situations where the wheel can be much more effective than engines alone. Though that does add some complication, and requires practice.

On the other hand, I'm totally with you re.shafts, and can't really understand Solitaire's point.
It probably also depends on the type of boat (lighter ones being possibly more responsive to rudder), and it surely depends on what we actually mean when talking about maneuvering.
As soon as I'm out of my berth, and moving around the marina, I do use also the wheel, but that's not maneuvering anymore, in my view.
For strict maneuvering, I would invite Solitaire to the following test on my boat:
He can helm the boat and maneuver to her mooring, using throttles or wheel as he wants.
In the background, I just play a little bit with the steering pump, turing it on and off.
If he recognizes when the rudder is actually moving and when it isn't, he can keep the boat.
 
Exactly my point. But we are not talking about out drives.

I was once in Falmouth, and a woman came up and said. Did I just see your boat going side ways, Well yes it did. But in reality, it was umpteen changes on engine power. Sort of like a ferry glide, except geting the boat to move side ways. in a small area.
Very quick sucsesions of power fore and aft. But more fore than aft maybe. Eventually. the boat is drifting. in the right direction. Cant explain it properly, but you can quite easy drop into a berth, with a foot either end. Closer if you have a good enough crew and can hold the boat, not going forwards or back. I can hold the boat on engines, but not all day, sooner or later I have to sort out the ground crew.

I to would like to think that there was some merit in Solitairs point, after all, he is a trainer.

Worrying init.

The boat answeres on a sixpence, Cant really understand why
Solitairs veiws differ.
 
I am not saying that you use the helm all the time! Of course there are situations when "waggling" the helm has no effect what so ever and is totally irrelevant. When I start with those new to shafts then, yes I get them to turn the boat with helm centered and then introduce the helm in certain situations - for example turning through 360 in an aisle!That is what I mean about a structured approach over time - normally by the end of the first day.

Many new boaters think that the wheel does the same thing as it does on a car, they waggle it, they turn on opposite lock when reversing etc etc. We have to break that mould and then start building up again. The trouble with you is you don't actually see the bigger picture, you don't see the problems with new boaters day in day out like we do. It's about teaching the principles correctly in the first place - then you can break the rules!

I very happily move a boat on shafts simply using throttle control (and I seldom use the bow thruster either, particularly on boats under 40 ft!) - what gets me is that old hacks like you state "oh you never use the helm" - well bully for you. But the aim is to teach people the difference and make their lives easier in certain situations and give them an appreaciation of the effects.
 
The way I teach it is , you have 3 gears almost to make a shaft boat turn,
for a turn to port,
1, put starbourd trottle into gear forwards,........ this creata a gental turn to port......
2, turn wheel /helm hard to port,...this will shorten the turning circle, also allowes the throttle to be return to neutral as the momentum/ water flow over the rudders will contiune the turn.
3, put port throttle into astern ......... acts like a hand brake pulls the boat back and aids the turn.


2 and 3 can be swapped round, why the helm over helps is that the forward thrust on the props is always just that little bit stronger than the astern, varies from boat to boat how much. and the helm over helps maintain postion and uses that froward trust to aid turning.


so helm over does help on a forward turn, but is [--word removed--] all use astern most of the time so leave it mid ships for going astern.

just my 2 pence worth. /forums/images/graemlins/laugh.gif
 
Well, thank you at least, for some what coming round to what I have said. Rather than confusing the guy by saying I and others are talking crap. Personally, I'd only think of using the helm if I'd uddles of space and just want to make a quick right or left turn. Mostly, I cant be arsed.

You seem to be being pedantic for no purpose, other than to protect some magic properties about your job.

The guy in question, is obviously getting confused, having come from a single engine and now having two. So is now using the wheel as you would with one engine, plus trying to use the two engines s well. What ever he's doing is obviously not working.

The simple answer is. DONT USE THE WHEEL.

Now please dont say I'm talking crap. Then try to wheedle out of it with some technical pretence.

THE BOAT WILL DO ANYTHING YOU WANT, WITH ENGINES ALONE.

Using the wheel might aid it, in a small number of situations, but more likely cock it up if not done right.

Now, is that pedantic enough for you.

I dont have a bow thruster, neither do I need more confusion added and more buttons to press by having one.

But to get pedantic again, there may be twice a year when it might be usefull.

Please refrain from getting on your high horse and rubbishing others advice, who may not be "experts" whatever that means. It's counter productive to the guy looking for help.

Less it's just a case of protecting your industry of course.
 
Mmmm... I'm beginning to think that - in spite of the fight between you and Solitaire on what was said about each other's comments - you're not actually that far with regard to practical recommendations.
After all, he did say When I start with those new to shafts then, yes I get them to turn the boat with helm centered, though I can assure him that (with my boat at least) even for turning through 360 in an aisle the rudder is totally useless. Actually, it is useless at anything below a couple of kts - make it three in reverse.
But then again, it's a 35+ tons boat with a long and deep keel (and smallish rudders) that I'm talking about.

Congratulations for being able to easy drop into a berth, with a foot either end, anyway!
I understand exactly what you mean by using fore and aft power (with the engine opposite to the berth, I assume), but frankly I wouldn't dare trying that with just a foot either end.
Not that rudders could have any use, also in such situation!
Only a bow thruster would be effective, particularly with crosswind.
Just to be a bit pedantic also myself, If I had one I'd probably use it 3 or 4 rather than just 2 times per year...
...but making a hole in a displacement hull for the thruster is almost offensive imho!
 
? I didn't mention rudders.

HLB says he can move his twin shaft boat sideways into a gap one foot bigger either end than his boat. I didn't know you could do that without using the bowthruster, and I was asking how.
 
[ QUOTE ]
Well, thank you at least, for some what coming round to what I have said. Rather than confusing the guy by saying I and others are talking crap. Personally, I'd only think of using the helm if I'd uddles of space and just want to make a quick right or left turn. Mostly, I cant be arsed.



[/ QUOTE ]

I never once said you or others were taking crap, nor in my view did I imply it - my words were that not using the helm at all was a fallacy. You choose to start sounding off - but then you always do!

It's got nothing to do with being protective or for that matter pedantic - that seems to be your trait. Anyway, enough is enough. You have a nice day /forums/images/graemlins/smirk.gif
 
Well, since the whole discussion was about whether a boat with twin shafts is better off when maneuvering using just the sticks or also the wheel, I assumed you were suggesting the latter.
Apologies, you're of course correct if you mean that the thruster makes life easier, if and when you must move just sideways.
I agree with hlb anyhow, using fore and aft power in short sequences (he didn't mention, but I would add with the same engine - the one opposite to the direction where you want to go) you can slowly move the boat sideways.
But as I said, personally I wouldn't try that with just a foot either end, not to mention against any meaningful crosswind or current.
 
Not sure I actually said that. Yes It's quite possible to get in and out of gap so small, it's only limit is how secure the crew can hold the boat till the engines are turned off.

Going sideways requires a bit of practice and hard to explain.

From say a standing start, say 12ft from the pontoon. Rapidly change both engines forwards and astern (one forwards tuther back) Get it right and the boat will at first start to zig zag towards the pontoon. After a few little zig zags. Hardly moving forwards or back. The boat takes on a sideways momentum and will drift towards the pontoon, whist you then ajust, bit forward or back, to fit in the gap.

Tutherway of course to get into small gaps. Just drive the bows in, close'ish to boat infront. Crew lassoos a cleat, a bit further back, so it acts as a spring. Ajusts rope, till theres say a foot to boat infront. Then keeping the rope tight with inside engine, bring the arse end in. Course, you may then find, it's not going to fit, so just reverse the process. Or drop the dinghy and anchor a bit and gain a foot or two.
 
I would say then that it takes lots of experience and practice to move sideways in the manner you describe, and I wonder how much sideways momentum you can get against a cross wind or tide? Surely much easier for most people to fit a bowthruster, then its relatively easy to move sideways?
 
You asked how you could get a boat to go side ways with just the engines. I told you. I said it took a bit of experience.

Mostly though, as plan B, just drive the bow into the gap, equipment required, a big round fender close to the bow 20 squid or so. Same fender is used to swing the arse end out when leaving. No faffing about with wheels or bow thrusters. Just two hands on the big sticks. Swing out, reverse, simple.

In my case, on the last berth down the isle, a bow thruster would be as much use as a chocalate tea pot. I have to leave the berth at 90deg. Arse end first.

If folk just watched how the little ferry boats, skery about, they just have one engine and no bow truster. There moored in about five seconds, then out again in six.

A couple of 200 plus hp engines, will beat a weedy bow thruster any day, course the marketing for big round fenders does not have the same budgit as bow thrusters.

Bow thrusters do have there place. Reversing into finger berths ferinstance. But mostly, there just adding complications to what is a simple task.
 
[ QUOTE ]
From say a standing start, say 12ft from the pontoon. Rapidly change both engines forwards and astern (one forwards tuther back)

[/ QUOTE ]Interesting. I can get similar results, but using just one engine - as I said, the one opposite the intended direction.
Where do you start from with your technique, let's say you want to move sideways to stbd, port engine fwd and stbd engine astern I guess?
 
Imagine it ike this. An exageration and in slow motion.

You drive the bows towards the bank, then bring the back in, then the bows again and so on. But if you do it slowly, you need loads of space, because you create no side ways momentum.

Done very rapidly, you neither move forwards or back. But the side ways momentum builds up. Once you have got enough sideways momentum, stop. Just use the engines for adjusting into the gap as the boat slides in.

It's not the sort of thing you need to do very often, as there are other ways of getting into the gap.
 
Having just got back from a week away with a good internet connection but a phone that would not let me post I have been following this with a touch of intrest!!

For my twopence worth, yes you can do just about anything you want on a twin shaft boat with just the engines alone, and I would recommend that for a beginner, But as you get more experianced and go out in more challenging conditions you will have a day when the wind is stronger and you will need to use more power to get the boat to turn and overcome the momentum of the wind.

The point about the helm is that it allows you to do the same manouvre at much lower power - usually tickover unless its really windy, this measns that you have a back up plan of incresing engine power if really needed.

Use of the helm is not for everybody and thats absolutly fine, but since the rudders operate about a third of a boats turning ability (and remember that they only operate on an engine in ahead)and also reduce forward creep it seems worth experimenting to see if it helps on your boat!
 
You have just explained exactly why I said, dont use the helm. Firstly, it's advice to a newbie. Secondly. The rudder only helps when going forwards at a few knots. Therefore in my oppinion, not in close quarters. Thirdly once you have used the rudder, presumably to get into or leave a close quaters postion. You then have the extra job, of centering the wheel again. All for no reason, except to maybe save a few revs now and then, whist at the same time confusing even the experienced enough, to make a big cock up.

Useing the wheel and gears best left till leaving the marina or in open water, when it really dont matter anyway.
 
I dont get the statement "and remember that [the rudders] only operate on an engine in ahead". Of course they work in reverse. OK they work less effectively than when the engines are ahead, but they still work to an extent. They work any time there is fore-aft flow of water over them, which happens both when engines are forward and ahead, and when the boat is drifting forwards or backwards.

But in general I agree with hlb on this. For a newbie, and for an experienced helmsman 99% of the time, it makes more practical sense to leave the wheel amidships
 
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