Degree of a 26X before she rolls?

[bbenkert26x]

Hello everyone!
Hope everyone had a great Memorial weekend?

Question on my 26X 2000 with a 50 hp Bigfoot on it........... My wife and I, fully loaded inc water ballast, were crossing Port Charlotte Harbor going south in the I.C. to Pelican Bay Saturday night just after dark, best I can tell winds were out of the east, north east with gusts around 30-35 knts and 4-5 ft seas, not once but twice I thought I was going to roll her, the prop came out of the water as well! CB was up, rudders were up and I was under full motor at 8-10 knts sometimes I would take a wave over the bow and get drenched! Not a good situation at would say.............. how far over can I put a 26X before I roll her?

Capt. B

[Don T]

Here is my figuring of the righting moment with ballast in.
http://www.macgregorsailors.com/modt/in ... ?view=1234
The righting moment does not improve after 46* but is still sufficient to right the boat when knocked down with sails furled as long as water does not get into the cabin. This does not include broaching where the waves drive the boat over, rolling or pitch polling. I avoid a broaching sea in heavier weather in the MAC as it is narrow forward and tends to roll a lot.

[Russ]

I'm not sure I buy this diagram. Does the last image show the ballast empty? With ballast in, there is a LOT of weight pulling the boat back up. Yet for some reason, Roger seem to think adding foam to the mast would help. I don't know, maybe help keep it from rolling over.
As long as there is ballast in the bottom, I would think the boat would want to right itself once the forces pushing her over subsided. Like weebles, they wobble but don't fall down because of the weight at the bottom.

[dlandersson]

Understand that the Mac 26's have such high leeboard that winds like you describe can make her hard to handle.

Hello everyone!
Hope everyone had a great Memorial weekend?

Question on my 26X 2000 with a 50 hp Bigfoot on it........... My wife and I, fully loaded inc water ballast, were crossing Port Charlotte Harbor going south in the I.C. to Pelican Bay Saturday night just after dark, best I can tell winds were out of the east, north east with gusts around 30-35 knts and 4-5 ft seas, not once but twice I thought I was going to roll her, the prop came out of the water as well! CB was up, rudders were up and I was under full motor at 8-10 knts sometimes I would take a wave over the bow and get drenched! Not a good situation at would say.............. how far over can I put a 26X before I roll her?

Capt. B

[bbenkert26x]

Roger that....... had my hands full, had I not been sailing a long time, it would of been ugly.......... doesn't handle like my 33 ft Hunter I had, that is for sure, she would of ate it up!

[Russ]

Roger that....... had my hands full, had I not been sailing a long time, it would of been ugly.......... doesn't handle like my 33 ft Hunter I had, that is for sure, she would of ate it up!

My Hunter 34 was a LOT heavier and had 5000lbs of ballast and could stand up to a lot. The entire Mac doesn't weigh that much. You can't compare a Mac to a keelboat. It's built to be light and trailerable. VERY tender at the beginning until the water ballast kicks in. Lots of windage to get blown around. With that said, I don't think it would roll completely over. But it gets scary at times. And as you observed, the motor's prop get lifted out of the water when it goes over.

Best advice is to stay in port on bad days. It's just not a heavy weather boat.

[Phil M]

How about this for advice?

If you head into a very strong wind, then motor slowly.
If you can use your furled genoa and double reefed main, and not travel head to wind, even better. The Mac prefers to be sailed in tough conditions, if you must be out there.

[pmmcderm]

For the CB/CG diagram, I think the last two hull diagrams are wrong. CB will be at the center of the displaced underwater shape, which will shift outboard on the "down" side as the boat rolls, as well as "up" as the the side of the boat displaces water. IMHO, CB shown is almost right, but a little high (when boat is upright). CG doesn't move unless all your stuff you forgot to secure for sea falls "down" to the side of the boat, your unsecured gas can slides across the cockpit, crew and captain end up in a pile on the new bottom, and you forgot to close the water ballast gate valve. CG may also move a bit if you dunk your sails.

On my , I can attest to sailing very poorly (skill, not boat) in 25 kts + 35 gusts and having her blown over to about 60 deg heel with me hanging on the mast (feet dangling over water ). She eventually rounded up when the gust let up, and righted, even with me hanging on to mast about 5' up. Unfortunately, I didn't think to take a picture .

Still not a pro on 'ikena maluhia, but I have learned that "uncomfortable" does not equal "unsafe."

[Don T]

I'm not sure I buy this diagram. Does the last image show the ballast empty? With ballast in, there is a LOT of weight pulling the boat back up. Yet for some reason, Roger seem to think adding foam to the mast would help. I don't know, maybe help keep it from rolling over.
As long as there is ballast in the bottom, I would think the boat would want to right itself once the forces pushing her over subsided. Like weebles, they wobble but don't fall down because of the weight at the bottom.

Let me explain,
You will notice that the cabin is filled with water in the last 2 images. Once that happens the ballast is rendered useless. Once the water ballast is surrounded by water which is equal in density the righting moment provided by water ballast is gone. If the ballast tank is empty and the cabin fills with water, the buoyancy of air in the tank holds the boat on it's side. There have been a few pics of Macs being towed back to shore in that condition. It's a function of the center of buoyancy VS the center of gravity. That is the main reason Roger decided to have some permanent ballast in the M model. It has a higher density than water so if the cabin fills there is still some righting moment. The water displaced has way less mass than the lead that displaced it so the center of gravity stays closer the keel. Foam in the mast provides buoyancy in those conditions and when trying to right the boat you don't have to lift the weight of the water out on the end of a 30' lever.
It's why our boats are "tender," because water isn't as dense as lead so it takes more degrees of heel to move enough mass off-center from the buoyancy. The S & D boats have a narrow, low ballast tank so it hardens up faster than an X boat with it's tall, wide tanks separated by the "6' standing headroom in between.

Also if you measure the force required to hold the boat / mast over, you will find the force does not increase after 46*. This is because the center of gravity is horizontally positioned next to the center of buoyancy. Any increase in angle lessens the lever. That doesn't mean there is no righting moment, it just means it doesn't improve.

I hope that makes it a bit clearer.

[DaveB]

Hi Capt.B,
Was great meeting you and your wife this past weekend.
We arrived at Cayo Costa 3pm Sat. after a 28NM trip from Cape Coral and sailed with good winds most of the way.
We saw the Sand Spit on N. Pelican Bay loaded with Weekend warriors and decided to ancor in the Lee of Ponti Blanca 1/4 mile south of the spit.
We had to take down sun awning around 8 pm and secure all rigging as winds were kicking up. I saw on my Iphone around 9pm Gasparilla Island Bridge monitor stateing wind Gusts of 35 mph out of the NE to ENE. Must have been heavier in Charrlote Harbor.
Winds and waves were on your beam, short steep 3-4 ft. waves and asume you were bare pole running engine with all boards up.
I would have left centerboard down about 2 ft. and rudders down. I also would try to limit heel to 25 degrees.
The centerboard and rudders on a beam sea will reduce Leeway but more important is the breaking waves will hit the centerboard and rudders to prevent capsize.
As the wave rolles under you the pressure on the boards will keep the boat upright incase a freak wave tries to get under you to flip.
Anymore than 25 degree heel will alow the breaking wave to get under you.
Downwind, beating is much diffrent and can heel much more under sail (not with motor).
If you get in those conditions again I would just use headsail reefed to 32 sq ft or less and make 5-6 knots.
These boats don't like beam breaking seas 3-4 ft. motoring, much better ride with the headsail deeply furled.
Most of the time when winds just come on to strong it is much easier to take main down than to reef and use headsail. I can furl much quicker in the roller furler and can beat to 45 degrees or less .
Dave

[dlandersson]

No picture???!!!

Unfortunately, I didn't think to take a picture .

[Russ]

Let me explain,
You will notice that the cabin is filled with water in the last 2 images. Once that happens the ballast is rendered useless.

Gotcha!

Yea, if the cabin fills with water all bets are off. However, the design of the Mac makes this unlikely. The companionway is narrow enough that it wouldn't fill if pulled over. You can see this on the factory brochure where they pull the mast down and the boat does not fill with water.


The Original question is how far can the Mac tip before going over. I don't think it would ever STAY over with ballast in.
Also, I do believe the OP was under power alone, not sail.

--Russ

[pmmcderm]

...
You will notice that the cabin is filled with water in the last 2 images. . . .
...
I hope that makes it a bit clearer.

It does help clarify your point, and I was thinking of my when looking at the diagram. What I have learned is that during bad weather, put the companionway cover back in. Not going to get the cabin flooded that way, so you really do end up with a Weeble.
Mostly helps my peace of mind, but that gets to the "uncomfortable" vs "unsafe" I was talking about.

So, I think if an rolls to 90+ deg, she'll come back up, to answer the original post. I've had mine to ~60, and she came back up pretty quick, even with a lot of extra weight up high.

Mahalo!

[DaveB]

You are looking at flat calm waters, picture 3-4 ft. breaking waves on the beam. You will roll over with ease. Also compare with a engine on it and equiped for cruiseing.
In those conditions that picture would have done at least a 360 if it didn't just stay bottom up.
In heavy conditions you always want all hatches closed and secured. If you do take a nockdown at 90 degrees, chances are it will come back up if boat is sealed, another wave may keep you at 90 degrees, trial and error, hope we never find out.
If the boat fills with water no bets as this will offset any water ballest as the weight will far excead the ballest in short time.
On my boat the air ballest plug is so loose a 90 degree knockdown would have water pouring out of it along with plug...time to get new plug.
Dave

[bartmac]

Totally calm water..in a river ...got hit by a 5-6 ft wave...side on at anchor (probably with rudders down not sure of centreboard)... from a floating footpath at speed (very close) as it went from displacement to planning...well!!! our mac26x nearly laid on its side...ballast in with 3 people in cockpit and one asleep inside...we got picked up and laid one way and as the very steep wave passed got thrown the other way......even further...certainly surprised us all