Mac 26x lead (C.E. to C.L.P)

[misterww]

Does anyone know the lead (distance from the Center of Effort from the Center of Lateral Plane divided by the LWL) on the Mac 26x, assuming a standard factory rig with main and jib?

If I have to guess I'd say about 10%??

Thanks in advance!

[misterww]

To qualify my question a bit, I was on a broad reach out of Lake Michigan Friday night with 30 mph (26 knot) wind gusts. Not the wisest scenario, I know. The heeling effects were clear and there was not heading up, but I'm looking for weather helm effects and thus the question on lead (pronounced like reed). I didn't get wet so yeah for MacGregor! Still, I'm wondering the performance limits of my boat from a technical perspective apart from the on-the-water mess I was nearly in.

Again, many thanks to all who can give some insight here.

[Gazmn]

While I can't answer your question, sorry. You kind of remind me of a person caught in the crossfire of a gunfight - & wondering the muzzle velocity of the bullets whizzing by. I don't mean any disrespect but making light of the situation. You present one of the situations that a Mac can excel in, & not because of it's CE : CLP but the grace of having a 50 or higher HP "Get the hull out of dodge" motor on the back

We don't belong out in 30 MPH winds, Cap...

[Obelix]

There is a short video out by Roger Macgregor, having the 26M out in gale-force winds in the Pacific.
Great video and Rogers advice the boat can handle it, but avoid these conditions if you can.
https://www.youtube.com/watch?v=SI0GumzxYt4
I would follow his advice.

Obelix

[paul I]

Does anyone know the lead (distance from the Center of Effort from the Center of Lateral Plane divided by the LWL) on the Mac 26x, assuming a standard factory rig with main and jib?

If I have to guess I'd say about 10%??

Thanks in advance!

Ummmm. Yeah.

Where is Tomfoolery when you need him?

[Judy B]

To qualify my question a bit, I was on a broad reach out of Lake Michigan Friday night with 30 mph (26 knot) wind gusts. Not the wisest scenario, I know. The heeling effects were clear and there was not heading up, but I'm looking for weather helm effects and thus the question on lead (pronounced like reed). I didn't get wet so yeah for MacGregor! Still, I'm wondering the performance limits of my boat from a technical perspective apart from the on-the-water mess I was nearly in.

Again, many thanks to all who can give some insight here.

I think you're pursuing a dead-end path of inquiry. You can't predict the limits of your boat while heeling using just CE and CLR (and, therefore, Lead) . CL and CE and lead are pretty old fashioned concepts. It's an old fashioned concept that predates the advent of computer analysis. CE is no where near the origin of the the drive (lift) and heel (drag) vectors generated by the sails. Modern CFD areodynamic and hydrodynamic analysis has shown that the actual center of lift is nowhere near the geometric center of the sail area. Same thing goes for CLR

The lead is useful to compare similar hulls with similar keels and similar rigs to each other. But when you don't have a similar hull to compare it to, you can't draw many (any?) useful conclusions.

Judy

[Jimmyt]

misterww,

Were you on a broad reach in 30 with your full rig up? Or, are you asking about a reefed configuration? Just curious. I've been on a broad reach in something just short of that, but I didn't have much sail out.

Just thought you might want to specify the actual sail plan that you were analyzing.

At any rate, glad you made it back in to ponder this obviously provocative topic....

[misterww]

Thanks all for the questions and feedback.

Judy, great point. Is there any scientific (i.e. fluid dynamics) analysis available to most sailors? Where can one find this detailed analysis/data? Seriously, I would love for an average boat buyer/owner to have access to this technology for informed decisions. Absent of that I think tradition prevails, right?

Jimmy and Gazmn: Lake Michigan in the early part of summer has lake breezes since the water temps are still quite cool producing light winds with some rather unpredictable gusts. Later in the season the winds come from the south and west, shielded somewhat from the city (Chicago). My sail plan was full sail then went to half reefed factory jib and main, then no jib and reefed main only. This sequence, along with the adjustments to the centerboard position, generated my inquiry. On the particular day that I was out the owner of a Catalina two slips down from me commented that he was surprised I went out that day, not that I came back

[BOAT]

Been there, done that.

I can tell you the M boat floats really good on it's side:



Unlike most sailboats that do not float well on their sides and take on water at 90 degrees:


(This is what an ODAY looks like at 85 degrees)


In fact, the MAC M boat is probably the only boat you can buy that has almost the same hull profile under the water line at 90 degrees as it does at zero degrees!



Thus the common nick-name - "the Clorox Bottle"

[gabid]

Does anyone know the lead (distance from the Center of Effort from the Center of Lateral Plane divided by the LWL) on the Mac 26x, assuming a standard factory rig with main and jib?

If I have to guess I'd say about 10%??

Thanks in advance!

For an , the CLP will change with the amount of centreboard out.

[Baha]

I would always allow for gusts when deciding how much sail to put up. I also sail where there are very variable winds, and my comfort level is to go a bit slower and not have to have one hand constantly on the main sheet and both eyes on the water. Plus, the gusts I deal with can routinely cause a full Chinese Jibe if I have too much sail, which never puts me in a good mood. My RYA instructor used "slow is pro" in almost all boat handling situations and it is the best advice I have ever gotten.