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Old 07 August 2011, 05:35   #11
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The upwind/downwind penny has just dropped...
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Old 07 August 2011, 11:54   #12
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Originally Posted by gtflash View Post
Im confused by the upwind and downwind now.... Upwind is not making the boat move up into the wind?? drunken ribneting! WOW my life is exciting.

Doug, it was a closed pontoon, and yes I couldnt see it until I got there plus a 40fter was moored before it. However the empty mooring to the left or port was the end of the road, of the dead end of the pontoon, so going past, turning round 180 did not appear to be an option, especially as i was aware the left hand stern of my boat would drift with the wind and tide mid 180 into the end of the pontoon. Therefore coming into the wind was not an option, nor asking a mate for help, as yesterday I did not have any .

How would turning 180 to port help? Im a little unsure why, I suppose I should have done it before the berth?

I did have front rear and midship ropes all ready. I am happy I chose to allow the boat to drift, controlled the port stern from slamming, with throttle, then pulled it over, however if that wasnt an option Id love to have a clear answer in my head. Tell them I want another berth?? Interesting feedback thanks
.

There are a few principles that are well worth getting in to your head/.

1/. TIDE- the whole boat moves equally with the tide, i.e. the bow and stern will both move downtide at the same rate regardless of which way the boat is facing. When you hear phrases i.e. the tide caught my stern the person talking is talking nonsense, the tide catches the whole boat equally.

2/. WIND- The wind will blow the whole boat down wind but it will blow the bow downwind far faster then the stern (as the stern has more boat, engine, rudder etc in the water providing resistance). The bow therefore will eventually end up downwind of the stern.

WIND AND TIDE DO NOT THEREFORE HAVE THE EFFECT ON THE BOAT

3/. REVERSING- If you try reversing into the wind the wind will hold the bow down wind of you (see point 2) and effectively allow you to reverse in a straight line easily. If however you reverse downwind slowly the wind will blow you bow of and force you to use more revs to go in a straight line. For this reason stern first into down wind and down tide berths is not generally a good idea but stern first into upwind berths works quite well.

4/. STEERAGE To have steerage (and therefore control) you need water passing over your rudder (or in the case of an outboard over the engine itself as it is your rudder). If therefore you point the boat into the tide and apply some reverse you will be moving forward through the water and have steerage. It may be however you are actually stationary in relation to the ground although you are moving through the water which is moving against you. In this instance you have plenty steerage and plenty control. This is one of the key reasons we prefer to berth into the tide. The opposite is berthing downtide. Say the tide is doing 2 knots and your boat in neutral you will have a 2 knot ground speed but you will have no steerage. To gain steerage you need to put revs on, which then results in a 3 or 4 knot ground speed. (and therefore 3 or 4 knots of speed towards the pontoon or any hazards. Not ideal!

4/. TURNING. If doing a 180 degree turn in a confined space you initially have to decide wether to turn port or starboard. If you turn downtide, you will be very quickly pushed towards your downtide hazard. If however you turn uptide you will make far less progress towards your up tide hazard (as tide is pushing you away from it) and you will have more steerage for lower ground speed (see above). In a knot or more of tide it should be possible to tun into the tide with low revs and short bursts of forward and neutral without actually making any progress over the ground. Ideally therefore we turn into tide.

Hopefully the above point answer several of your questions.

Going back to your original question and factoring in that you were at the end of the fairway with no room to turn around, I would sugsget going stern first down the uptide side of the fairway. As you slow down the wind will turn you bow downwind. Once your stern has cleared the pontoon you want and it starts to become open allow the wind to blow your bow further downwind as you start to drive slowly into the berth. If it goes wrong simply reverse uptide and upwind, re align and go again. Remember the wind will always put your bow downwind of you so all you have to factor in is your gear, revs and the tide.

As the berth next to you is also empty there is alway the option to stern first ferry glide in the last bit to straighten her up.

That's probably about as much as i can usefully explain in text without some images or better still a live demo. This is all stuff we cover on the Powerboat Level 2 and Dayskipper Courses.
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Old 09 August 2011, 17:36   #13
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Thanks Doug

I have done PB2, however frim discussions with friends, the only issue with doing PB2 is its, usually in a school boat, not your own (in my case almost half length) PLUS the instructor naturally takes you to his best spot in same marina, so its very practiced! I am not critisising all, infact I loved my PB2. Id reccomend anyone who does it should do it in their own boat!
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