Orca core and maps, what do you think?

[Sailorman97]

Originally Posted by s/v Jedi

Most people know what a 90 degree angle is and what an 80 degree angle is and they can tell the difference. That requires zero sailing experience. On sailing, I am doing that for more than 50 years incl. 10 years Laser competition circuit.

You first 2 sentences have exactly nothing to do with anything we are discussing here. No sailing experience means no ability to discuss the situation we have here which is tacking angle and course made good.

You have 50 yrs sailing experience and yet you don't seem to understand tacking angles and course made good enough to discuss them. Curious.

I think I will just end it here for because there is really no way of moving beyond this.

Enjoy

[fourlyons]

Originally Posted by s/v Jedi

Most people know what a 90 degree angle is and what an 80 degree angle is and they can tell the difference. That requires zero sailing experience. On sailing, I am doing that for more than 50 years incl. 10 years Laser competition circuit.

But Jedi, I would argue you are measuring the wrong angle. At least in the US, I learned that, when it comes to tacking angles, you measure the change in the boats heading from one tack to the other. In this screenshot I attached, you seem to be measuring the angle that the yellow arrow is pointing at, but the convention is to measure the angle that the red arrow is pointing at. That is why the more weatherly boat has a tacking angle, that is numerically smaller, let's say 70°.
If you're measuring at the yellow arrow, the more weatherly boat will have a higher numeric value for the tacking angle, but that's not how we speak about tacking angles. A smaller numeric tacking angle is the more weatherly boat.

I'm convinced you know all this, so I must not be understanding what you're saying.

Where is Wingsail, I want to hear from him on this?

[s/v Jedi]

Originally Posted by Sailorman97

You first 2 sentences have exactly nothing to do with anything we are discussing here. No sailing experience means no ability to discuss the situation we have here which is tacking angle and course made good.

You have 50 yrs sailing experience and yet you don't seem to understand tacking angles and course made good enough to discuss them. Curious.

I think I will just end it here for because there is really no way of moving beyond this.

Enjoy

I guess you are talking about the number of degrees course change. That’s all cool but remember you come from the US I guess and ai’m Dutch and you guys got everything messed up incl. even port and starboard tacks, but still using all the Dutch words for everything incl. yacht, schooner, sloop, boom, starboard, port and about every single name used around boats.

This is an International forum and you need to widen your view to beyond your local terminology. If you had said “I mean the number of degrees you change course while tacking” then you would have been clear.

[s/v Jedi]

First hit on Google:

Tacking angles vary widely based on the boat, the wind speed, and the ability of the skipper to sail the boat for best upwind performance. For most boats, in very light wind you'll tack through an angle of 95-100° or perhaps more. In strong wind, you could tack through an angle of as little as 70-75°.

[fourlyons]

Originally Posted by s/v Jedi

First hit on Google:

Exactly Jedi, the more weatherly boat there is the one tacking through 70°. Now look at the diagram I posted, there's only one place you can measure 70° and have it be more weatherly, that is at the red arrow. That is to say the change in the boats course from one tack to the next.

Even in Dutch, what you're saying doesn't make sense

[ozolli]

Well, in France, the tacking angle is the difference between both tacks.
Myself 44 years sailing, same racing.

[s/v Jedi]

Originally Posted by fourlyons

Exactly Jedi, the more weatherly boat there is the one tacking through 70°. Now look at the diagram I posted, there's only one place you can measure 70° and have it be more weatherly, that is at the red arrow. That is to say the change in the boats course from one tack to the next.

Even in Dutch, what you're saying doesn't make sense

We always talked about the angle indicated by the yellow arrow in your diagram.

Don’t you use wind angle and don’t you find it easier to flip that over to the other side instead of compass course change? We do a 50 degree true wind angle and thus our tack angle is twice that, 100 degrees.

When we do a port tack, it means the boom is at the port side and we have right of way. We yell “port side!” to the other boat, not “starboard tack!”

[ozolli]

Originally Posted by s/v Jedi

When we do a port tack, it means the boom is at the port side and we have right of way. We yell “port side!” to the other boat, not “starboard tack!”

Again, in France, the right of way boat yells "Tribord !" which means starboard, as it sees the wind coming from starboard.

[CaptainRivet]

Originally Posted by bergius

There are two ways to get polars into Orca for weather routing: either import from the ORC database, or let Orca learn your sailing behaviour.

Since our boat can’t be found from ORC, and we can’t import custom polars, this should be based on its learning behaviour.

We installed Orca Core this winter, so all sailing we’ve done with it has been with new sails and in flat water on the lakes around Berlin. I’m sure the tacking angles become less ambitious once we get some data from at sea

Could you please tell us the actual tacking angles...if i am not completly blind and need an eye doctor visit every tack on the screenshot has angles above 90degrees, assume 100-110.

[Sailorman97]

Originally Posted by CaptainRivet

Could you please tell us the actual tacking angles...if i am not completly blind and need an eye doctor visit every tack on the screenshot has angles above 90degrees, assume 100-110.

Tacking angle is the difference in degrees between your old course and your new course. All of the changes pictured here are less than 90 and closer to 80.

I am referring to post 16.

Forget about the graphic. What compass course is the boat making before the tack and what compass course is it making after the tack. That is the tacking angle.


Yesterday you said.

Just look on the graphic route and you see the tack angle is greater then 90, assume 100-110 degrees and thats typical tack angle for a good mono.

Your statement yesterday is completely incorrect. I also don't consider 110 degrees to be a typical tacking angle for a good mono. It is fat cruiser tacking angles in relatively flat water with relatively good sails. Your typical performance racer cruiser a 6-6.5 keel with good sails can point 27 degrees apparent and can make a true course of 40 degrees off the wind.

Example: wind out east at 90 degrees true. A well found and well sailed racer cruiser in relatively flat water can sail a course of about 50 true on starboard. When it tacks to a port tack it can then make a course of about 130 degrees true.

What is the difference between 50 and 130? 80.

Hopefully we can now seep this one into the bin.

[s/v Jedi]

Originally Posted by ozolli

Again, in France, the right of way boat yells "Tribord !" which means starboard, as it sees the wind coming from starboard.

Big differences between countries

At least you drive on the right side of the road

[fourlyons]

Originally Posted by CaptainRivet

Could you please tell us the actual tacking angles...if i am not completly blind and need an eye doctor visit every tack on the screenshot has angles above 90degrees, assume 100-110.

Your eyesight is fine.

You are measuring the wrong angle. Measure the angle at the red arrow, not at the yellow arrow.

Close the angle at the yellow arrow (where you are measuring) down to the 80 deg of a high performance boat and you will see it will reduce it's course made good.

[s/v Jedi]

Omg, now I see those wind arrows… even those point the exact opposite direction!

What is this software?

[sailingharry]

So, in post 17 I raised the question about the exceptional upwind performance of the shown track. 25 posts later, it seems I ignited a raging argument! I haven't (and won't!) engaged in the mud slinging and name calling, but I certainly didn't expect my comment to go this way!!

[sailingharry]

Originally Posted by s/v Jedi

Omg, now I see those wind arrows… even those point the exact opposite direction!

What is this software?

I think those wind arrows (in the little circle next to the wind speed, right?) are pointing INTO the wind, like a Windex (or a forecast for "north" winds which blow south) not WITH the wind, like Windy would show. Wind direction conventions are not universally consistent, always makes me nervous when I read them.