[davidpm]

One thing that is not immediately obvious is that the wind you feel is not true wind but a apparent wind which is a combination of the true wind and the wind you are making by your movement.

When you are sailing close hauled the wind may seem to be about 35 to 40 degrees off your bow so you may be tempted to pick a location 40 degrees off the opposite bow to head for when you tack.

In reality however with most smaller boat with tired sails the place you are likely to be able to aim to is going to be 90 degrees from your current course.

And of course if their is current your realistic new course can be wildly different.

But as to your calculation the 40 to 35 people are talking about is really off the wind angle so it is half of the full tack which is what you are talking about.

 

[davidpm]

If you're turning approx 90 degrees through a tack that's 45 degrees off the apparent wind I'd say that's pretty typical goal.
.

Would this be more accurate?

If you're turning approx 90 degrees through a tack that's 45 degrees off the true wind.

 

[davidpm]

Two other things that make a huge difference in the full tacking angle range is the current, waves and wind strength.

Lets take a not unusual situation. You are driving a standard beginner boat lets say a Catalina 25 with older sails.

• It's blowing 22 knots out of the North.
• The current is 2 knots North to south.
• The waves are two feet caused by the wind.
• You are trying to sail south to north (of course you are)

Now without the waves and current and 12 knots of wind you could tack through 90 degrees and fetch any mark you choose.

If you are making 5 knots boat speed the two knots of current are going to drift you off your 45 degree off the wind course by over 20 degrees so your full tack is now 135 degrees or more instead of your original 90.

It is worse though because you will probably have to reef and your speed will go down and with the waves and extra leeway you may be lucky to be able to go east and west and not make any progress north at all.

You will have to motor or do something else.

I only get to drive any given boat a few times a year so I'm sure folks that have a lot of experience on specific boats can tighten up my numbers.