Twin screw docking techniques

QBhoy

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Bit of a novel to follow, but here goes and hopefully starts an interesting post in these dark and depressing winter days and pre season !
So, my old fellow owns a stunning old Princess 385 with lovely tamd61 306hp's on shafts. She has extensively explored all the west coast of Scotland has to offer and faultlessly at that (hopefully owing to my meticulous servicing regime, year after year and the almost contorsionist abilities required to change the starboard engine oil filter).
Point being, my father now has to go in for a knee operation and won't be as nimble up and down the fly bridge steps as he used to be this season. Therefore, I will be tasked with close quarters manouvering.
Now, having had 30 years plus at handling motor boats from 18 foot to 24ft with a single leg outdrive, I fancy myself at anything such a boat can throw at me. In my own boat, even in a wind blowing me off the jetty, I can pretty accurately point the boat at around a 30o angle to the pier with a bit of forward momentum and at the last minute, turn the steering and hence the drive leg and prop toward the jetty and a nudge of reverse will see her slide in gracefully toward the jetty...almost in a sideways motion. Ideal !
This to me is fine, because the thrust is pulling the boat towards the pier whilst still having forward momentum.
With the big princess and no thrusters, it becomes a bit of a conundrum at to what option to go for.
The old man and his experience makes it look easy, to the point where an onlooker once commented on him "showing off with the bow thruster" that he doesn't have.
He tells me this evening that when going towards a jetty on the port side, he would be creeping in and out of gear on the stbd engine (with port in neutral) at the around 25-30o angle, them a quick nudge with the port engine in reverse would pull her in. It clearly works, but just interested to hear of others tekkers on this. With the steering on such a boat mainly relying on water travelling over the rudders, it's a different kettle of fish to what I'm used to...being able to physically move the direction of thrust with the leg.
Things are made all the more dramatic by the shear relentless power of the engines and fierce pitching of the props. Added to this, not being able to see the edges in relative to the jetty at close quarters, makes it all the more nerve racking.
Love to here of your theories and techniques, but I unlitmatly know that I'll no doubt find my way with her and practice makes perfect.
Allan
 
One tip I used to learn slow speed manoeuvring on twin screws that I have not seen on other threads is to look at the direction the throttle (handle) you are about to push or pull is pointing in as that indicates the direction your bow (push) or stern (pull) will try to move.
 
Thanks for this guys.

I would also suggest (from experience with twin engined catamarans but the principle should be the same) that you try it all out somewhere with plenty of space in flat water. The amount of control you have with twin throttles is quite incredible and intuitive even compared to a bow thruster. Obviously you still need to work to take advantage of windage not fight it but the ability to turn the boat in circles on the spot with judicious nudges of the throttles gives a lot of confidence.

I had a massive advantage the first time I tried it becuase I spent so many hours and days of my youth playing a game called BattleZone - but passing on the skills on a real boat to less nerdy friends was much easier than I expected.

For docking then I think of the offside engine as being a sort of stern thruster in reverse so you can both stop the boat and nudge the stern into the dock in a short space, provided the bow is already fairly nose-in when you do it.

But practice where there is space until you feel comfortable.
 
Excellent, I love to see women handling boats which is quite often here in Norway. In summer when they go out to their cabins on the islands its fascinating to see that at least 70 % of the ribs and dinghys are driven by lovely blonde teenage girls who come into the town quay to pick up supplies, so they learn at an early age. And I always taught my girlfriends to drive my powerboats as they often made the best ski boat drivers. Plus it was worth it to see the green faces of guys driving their boats while a I had a pretty girl driving me in mine. Sitting with a cold beer while watching a bikini clad beauty handling my boat is my idea of heaven.
 
Excellent, I love to see women handling boats which is quite often here in Norway. In summer when they go out to their cabins on the islands its fascinating to see that at least 70 % of the ribs and dinghys are driven by lovely blonde teenage girls who come into the town quay to pick up supplies, so they learn at an early age. And I always taught my girlfriends to drive my powerboats as they often made the best ski boat drivers. Plus it was worth it to see the green faces of guys driving their boats while a I had a pretty girl driving me in mine. Sitting with a cold beer while watching a bikini clad beauty handling my boat is my idea of heaven.
Why are only the good lookers allowed into town?
 
If you go onto 'you tube' and search for 'essex boatyards boating tips' the first clip is docking a twin shaft drive boat. Really good learning material.
 
Saw a YouTube vid the other day where a woman was berthing a sailing boat stern to while looking aft and steering from the 'wrong side' of the steering wheel ... got within about 10 feet of the quay and whacked the throttle the wrong way thinking she was going to stop the boat! I expect someone can find a link??

Found it:........... https://youtu.be/O-NkUKn5vyQ

and on a twin engine mobo for the OP: ...... https://youtu.be/frZNAc6jFac
 
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Saw a YouTube vid the other day where a woman was berthing a sailing boat stern to while looking aft and steering from the 'wrong side' of the steering wheel ... got within about 10 feet of the quay and whacked the throttle the wrong way thinking she was going to stop the boat! I expect someone can find a link??

Found it:........... https://youtu.be/O-NkUKn5vyQ

and on a twin engine mobo for the OP: ...... https://youtu.be/frZNAc6jFac
It's because of that that I always face forward and either look behind or use the camera. It's very easy in times of stress to react instead of pausing to remember you are facing backwards. This muscle memory is what gets you into trouble when going from à right side of the road country to a left sided one.
 
. . . but just interested to hear of others tekkers on this. With the steering on such a boat mainly relying on water travelling over the rudders, it's a different kettle of fish to what I'm used to...being able to physically move the direction of thrust with the leg. . .

At low speed when berthing a twin shaft the flow of water over the tiny rudders is not enough for steerage. Generally you centre the rudders and forget about them, instead using differential thrust to steer and manoeuvre the boat using the two throttle levels. There are times when you will also use the rudders to move the pivoting moment forward or aft, or to reduce the bow motion. We exit and leave our marina via an access channel but don't need to use the wheel until out of the marina. The technique on single shaft is quite different as the rudder is the size of a barn door and very effective with prop wash.
 
I went from transom power (singles) to shaft and rudder (again singles). All I can say is a shaft is better forward and reverse, with a little burst of power with the wheel hard over you can propwalk the stern in either direction. And true control of a boat comes when you can control the stern. This makes it possible to do quite intricate manœuvres in reverse. Transom power should make a boat reverse where you point the prop but in reality some boats don't always cooperate.
 
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