If you have to reverse in to a berth, start reversing in open water.
In most boats, it is very difficult to anticipate the exact reaction when you start to reverse. The propeller effect tends to pull the stern in one direction, and the wind will blow the bow off.
If you will be reversing directly in to the wind to reach the required berth, these factors will probably make it very easy to control the boat, and will allow a stress free berthing manoeuvre. However, with the wind in any other direction, in the confined space of a marina the outcome may be uncertain to say the least.
The best approach is to find an open space outside the marina, put the boat stern to wind, then start reversing. When the boat is under control, going backwards, just steer in the required berth. This is much easier than attempting a three-point turn in a restricted space-unless you really know your boat!
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