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Superior Sailor
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How do you measure the angle of a tack.... I hear people say there boats point at 40* or 35* (mine seems more like 90* between tacks)...

Lets say I want to go North (0*) and the wind is coming from the north...

Should I look at my compass on a starboard tack (say 40*) and then add the difference on a port tack (say 320*)...to come up with 80* and then divide by 2 for pointing angle...?

Or is there something else to the formula...?
 

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Discussion Starter · #3 ·
Whats the desired (preferred) pointing angle then....I know depends on boat/conditions of sails etc..

But in general what is the range of "normal" compared to what is too wide and needs to be addressed..?
 

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When your boat is close hauled (approx 45 deg off the wind) and you are facing where the boat is pointing the tacking angle will be just behind your windward shoulder. (approx 100 deg from your heading).

It is usually easier to find a point on the land or a convenient cloud but 100 degrees added or subtracted from your heading will do for a compass course.

Phil
 

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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.
 

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Hey,

Here are some basic numbers:

For a 'racer' you better be able to tack within 90 degrees or you won't really be competitive (I am referring to 'high performance' boats racing one design, not PHRF).

For a moderate cruiser / racer with decent sails, you should be able to tack within 100 degrees.

If you have a older heavy cruiser with older sails, then greater than 100, but I have no idea of the actual numbers.

Barry

Whats the desired (preferred) pointing angle then....I know depends on boat/conditions of sails etc..

But in general what is the range of "normal" compared to what is too wide and needs to be addressed..?
 

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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.

But, As YorkSailor points out, you might typically need to turn 100 degrees since you will lose some boatspeed and thus apparent wind speed ( and angle) once you turn. Once you get back up to speed you should be able to " head up" a little more. If your turn is too tight at first, you'll end up pinching. I'd also try to use a steady fluid motion when you put the helm over to minimize the "braking" effect of the rudder.
 

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Corsair 24
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Whats the desired (preferred) pointing angle then....I know depends on boat/conditions of sails etc..

But in general what is the range of "normal" compared to what is too wide and needs to be addressed..?
this is if your sailing in a pool in test conditions, in real life you need to factor in

waves
sea conditions
currents, eddies, drafts say from warm water to cold
physical objects like islands, jetties, piers, barges other boats
wind

angle is based on boat design FIRST...once you know what your boat should point to(using other owners experiences or the designers notes) then you need to play with the tune of your rig, sails, mast rake, bend...etc..etc...etc...

oh dont forget ballast, bottom paint...etc..

all will influence you tacking angles:D
 

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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.
 

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After a pretty good amount of playing with the VMG function I have found the turn left or right to give better info when the wind direction requires a lot of tacks to a waypoint

I also pay much more attention and helm to the jib telltales VS the windex to get the most out of each tack
 

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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.
 

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Just turn the wheel, and stop turning when you have the sails how you want them on the other side.

Seems easier than trying to guesstimate angles and such.
Some truth in this but it wasn't until I started trying to hit specific numbers that I started trimming the sails better (halyard tension, backstay, right jib lead position blah blah).
 
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