Where is the pivot point ?

[Petrolia]

Agree about reference points. Learned that on day skipper sailing course. And as you say I try to manoeuvre without bow thruster. Manage it more often than not.

Also agree about turning slowly while moving forward although I think you knocked the wrong engine into neutral ?

Also if you are running up a fairway with wind on the beam using the engine opposite the wind tends to negate the winds effect, depending on its strength of course.

 

[Petrolia]

Never thought about your last point but I see it. The bow thruster has more leverage against a pivot point that is further back, towards the aft of the boat.

So if I'm reversing into a berth with wind on the SB side. If I reverse on the port engine it will try to move the aft to starboard but turn the bow to port. So I counteract that and the wind with the bow thruster pushing to starboard.

So will the boat hold into the beam wind or even manage to move the whole boat to starboard ?

I'm asking because if there is any wind it always seems to be on the starboard side.

I think I confused myself.

 

[Bandit]

The props are put on not to give you favourable walk but to give you lift , if you put them on the wrong way round and after adjusting the gearbox controls etc you get squat which slows you down.

Petrolia, sorry I am was getting my P&S's mixed up ,

one engine, port slow ahead the boat will turn to starb (right) as the septics would say.

One engine Starb slow ahead and the boat will turn to port (left)

 

[stefan_r]

Don't forget a prop turning "forwards" is also more efficient than the prop going the wrong way - i.e. backwards so you will not pivot but move in a way I can only describe in a drawing!!!! But think about it or try it...you will move forwards even with equal revs and one engine forward and one reverse...

 

[Hurricane]

[ QUOTE ]
I think I confused myself.

[/ QUOTE ]
Think of the little "aid memoire" thats beed said on these forums before.
Look at the throttles - most have a curve on them.
Think that when the appropriate throttle is operated it indicates which way the appropriate part of the boat will turn.
Port throttle forward - curve is to the right and forwards so bow goes to starboard - therefore stern goes to port.
Starboard throttle backwards - curve is left and backwards so stern goes to port - therefore bow goes to starboard.

Now if you have the boat turning on both engines and you stop the bow turning by using a bow thruster, the whole boat should go sideways.

 

[Andrew_Fanner]

I usually reckin that if I do a neutral turn the pivot spot is just behind me at the wheel. I usually use the rudders.

 

[gjgm]

ooh, I like that. I think even I can remember that tip for those moments of panic! A good reminder that both ends of the boat will swing, too

 

[Petrolia]

Post should be been, "Why is the pivot point.." Not where. But whatever, some good input / advice. I'm definitely clearer now.

Thanks.
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