Originally Posted by turkish6
if i were to use no spring lines should i keep the rudder straight, then once i start moving back cut it. or is it better to keep it turned slightly before i throw her into reverse??
The rudder is completely inneffective with no relative water
flow over it.
If you were in a river flowing 10 knots and were floating with the flow (10 knots over ther earth) the rudder wouldn't do a thing. If you were facing up stream stopped (0 knots over the earth) the rudder would have 10 knots over it and would be very effective but you would be standing still relative to trees on the bank.
If you can understand that then try this.
Assume a conventional single
screw boat with the prop mounted ahead of the rudder.
If the boat is 0 knots relative to current
and you put it in forward and add throttle you will almost immediately get rudder effectivity due to water being forced across the rudder.
In reverse the same boat has zero steerage at that time becuase water is being forced forward. You have to wait for the boat to start moving to get rudder effectivity. In the meantime the boat is affected by current
, wind and prop walk.
In your case I can't help but guess that your docks are not "protected" by a breakwater and that they are exposed to a tidal current. I guess that when you have reversing trouble it is because the tidal current is flowing from bow to stern. Let's guess that this current is 1 knot
and you need 2 knots relative flow for good steerage. This means that your boat speed (speed over earth) would need to be about 3 kts.
When the tide is flowing the other way (stern to bow) you "already" have a water flow over the rudder (relative speed) of 1 kt and it becomes even more effective as soon as the boat starts moving over the earth relative to the dock. Your relative speed is 2kts and your speed over the earth is about 1kt.
2kts difference around a dock is very noticeable. At our dock we sometimes get almost 2 kts tidal flow.
If all this is true in your case you have a problem - You reeally don't want a heavy boat going 3 kts in reverse (relative to earth, docks and in close proximitely to other boats.)
1/ Check your tide tables or throw a leaf or something in the water to check tidal currents and see if my wild guess has any merit whatsoever. It is a total guess cuz we don't have enough info yet to understand what's happening.
If all the above were true here is how an experienced skipper
might do it.
1/ Drop the lines.
2/ Engage reverse idle and let the boat move with the current - rudder neutral or right -
3/ Put the boat engine
in neutral - rudder to right -
4/ As the bow clears the pylon engine
to forward idle.
5/ Rudder hard left - one medium burst of forward throttle until nose starts to swing left - note do not stop boat - boat still travels in reverse
6/ Rudder hard right engine in reverse idle.
If bow stops swinging left repeat 5 - 6. The key is the power burst in forward "blows" water across the rudder and starts the nose swinging the way you want while keeping a very slow boat speed.
Now add a wind from the port side and none of the above may work. if the wind is strong it just may not allow the nose of the boat to swing left.
Like I said. I depends.
You can practice this technique away from the dock and you should be able to do a 360 almost within the boats own length. Do it within one length of a moring and see how you do. Note how the wind affects the boat as you do these 360s. If you can do a 360 in wind + tide and finish with the boat in the same place you started you are a dockmaster!