Reversing a full or 3/4 keel boat is a lesson in patience. If you let the bow swing more than 5 degrees or so, it will continue fall off until it hits the pier or your slipmate. If you catch it soon enough, pumping the tiller to port (if falling off to starboard) can sometimes correct it, but no guarantees.
Lateral displacement of water by the props is resisted by "stationary" water. The prop wash/walk effect should only come on when there's insufficient resistance from some direction, in this case, the top side as there is essentially no water to resist the wash above the surface. If the prop is deeper in the water, the wash/walk effect is diminished.
Diminished, instead putting a counter torque on the boat's long axis, which would dip one side in a little over the other. Resistance by the boat's hull and centre of gravity stops the boat flipping in opposite direction to the spin of the prop. The net result is forwards thrust.
And what about when you want to reverse out/in to a berth ? Do you : 1. give the reverse a good hard short burst (Where should rudder be for this) and then drop into neutral and let momentum activate the rudder again ? or 2. Use almost no reverse and let her build her speed astern slowly without walk until the rudder becomes active ? I ask because I'm a full keeler (Contessa26) with a major walk. Reversing scares the bejeesus out of me in a crowded marina... and thats WITHOUT wind/current.
Good vid, very well explained. One observation I made was when you were demonstrating astern prop walk in the slip way, the wind was giving your bow a nice down wind boost, making it appear the prop walk was more significant than it was. Overall, very good video.
Almost all (non-saildrive) engines rotate the prop anti-clockwise in reverse (looking forward), which means the prop walk moves the stern to port - as here.
I know Im asking the wrong place but does any of you know a tool to log back into an instagram account..? I was stupid lost the password. I love any tips you can give me.
I been backing into my slip using a spring line as shown in the video Docking Techniques Demonstration. I highly recommend watching that video too. That could work for you. When I had my Oday 22 with outboard, hey you show me the slip I can back in blond folded. As I have learned the past few months, my Hunter 33 can sometimes be a stress festival trying to back into my slip using engine and rudder steering.
I'm always exceedingly sceptical about such videos as for precise maneuvering a GOOD outboard is hard to beat as one can vector the thrust. (By good outboard I mean one that starts first pull every time then runs as steadily a a well-oiled clock) Some people seem to be a cross between Mr McGoo and Mr Bean and they get the boat stuck in the reeds and the mud every-time. This is never their fault, its the fault of the council or the harbour authority who haven't dredged the river deep enough! Such a faux-pas cost me almost £1000 as my boat which was supposed to be being sailed out of the costly marina by live-aboard friends remained there with a horribly fouled propeller. The water was near freezing and the visibility was only about a foot so diving on it was virtually impossible even with a wet-suit. In the end I solved the problem of getting the boat to the boat club by fitting an outboard bracket and an outboard motor. Inboard diesels aren't all that they are cracked-up to be but perhaps a mud-motor propeller would help? LOL
There is a lot of questions unanswered here. Is this a right or left-hand prop? you don't clarify, prop walk in not clearly defined here, at .55 you mention that the boat kicks to port with prop wash to starboard, you don't mention prop walk here, is this what you mean by prop walk. It's still unclear what prop walk is. I understand prop wash. Please clarify. Thank you. Paul
informative video but it is unnecessary to go through the trouble of running the boat in gear while berthed. it is very easy to find manufacturer information for your specific engine online, or, failing that, observe the rotation of the prop shaft at the rear of your engine while cruising.