New 26M or Upgraded 90HP

[Frank C]

Rolf, Really have to disagree with you on this one. I have been in those type conditions routinely, .... Maddmike

Rolf, I disagree with that statement too. The Mac is a totally overpowered sailboat with a 50HP on it. In nasty seas, you can't even use more than 10% of the power of a 50. . . . IMHO.

WADR, there seems to be a disconnect here. Seems to me that both MM and Dimitri are speaking of a motorsailer in heavy seas. In such case the sails are providing the bulk of required power and stability, with the motor providing only "auxiliary duty."

Rolf is speaking of the Mac as a fully-ballasted powerboat in heavy seas. When seas are tossing the boat and threatening a broach at every passing wave, the Mac demands a large prop with lots of horsepower to maintain a steady course. In this latter case, all sails furled, the Mac requires the torque of the larger prop and motor.

I agree with Rolf, and maybe the other two-thirds of us who are not sail-experienced enough to face severe seas with sails aloft. In that case, an oversized motor is possibly life-saving.

[ken]

They know what they are talking about, I was caught in a Gale on Lake Huron 25 years ago in a 24 ft sail boat (6hp motor). This was one of the most frightening things that I have ever experienced in my life (16 to 20 ft seas) I was relative new to sailing and if it had not been for the fact that I was traveling with an old salt on another boat (Paceship 26) I would have had the big one. He was very experienced sailing in heavy weather and by talking on the VHF was able to keep my crew and I some what at ease during the 14 hours of hull. My point is, it would not have made any difference if I would have had a 300 hp motor or the 9.9. I could only go so fast and try to keep control of the boat. You are not any more safe with a 90hp as you would be with a 10hp if you are focused on keeping the boat together. Although I never experience anything like that with my 26X, I did have it in some rough seas, but only had a 18hp motor and had no problems with controlling the boat. The 90 hp may get you off the lake sooner, but if you get caught in rough seas, you won't be doing any better then the guy with the 10hp.

Ken

[Frank C]

I think the reference was to seas at 6 or 8 feet, not 16 feet. I understand your point, but I'd probably die in those conditions regardless of sails or outboard. Sounds as if you did have sails up, and would have feared the same absent that very experienced tutor being nearby .... or maybe I misunderstood?

I was referring to zero sails aloft - and there have been several days on SF Bay when I really, really wanted to drop all sails. I have managed six-footers without sails, due solely to the power of my large-propped Sucuki 60. I know it would have been vastly more difficult with less power & grip of a 50 to drive into the wave face - and I surely wouldn't want to try to drive the Mac into six foot waves with no sails and just 10 hp.

[Dimitri-2000X-Tampa]

Frank, are you going faster than hull speed when you are heading into those 6 footers?

[Frank C]

It varies. When heading into the waves, no, only at about 7 knots. Any faster can compress a disk, break a tooth, or split the hull.

When trying to run with the waves on a strong tidal current, yes, 8 to 10 knots. When current opposes the wind, the waves are steepest. And when you need to power into a fast-moving ebb with wind on the stern - that's the worst ever.

Even at 10 knots of boatspeed, with an opposing current your prop is sorta "slipping" as the current rushes from bow to stern. I know a 10hp could not have managed in that condition, and a 50 would have been difficult. The current is robbing your horsepower, kinda like being on a treadmill. Meanwhile the wind-driven waves are quartering you and trying to broach you 4 to 5 times each minute. I had four souls aboard, plus my own worthless hide, and it was the most scared I've experienced, trying to prevent a broach, or worse. The objective, if at all possible, is to match boatspeed to the speed of the waves, holding the boat up on the backside of the wave that just passed you.

P.S. those conditions - on a run in opposing current, I'd have surely beaned myself or another with the boom as the water skewed the stern like a fishtailing car on ice - a good reason to go it with sails down.

[Moe]

Sounds like a good situation for a drogue.

[Dimitri-2000X-Tampa]

If I remember right, hull speed is closer to 6 kn in this boat. I wouldn't have the main up in those conditions either although I've observed that a little bit of headsail usually will help stabilize the rolling. I'm pretty sure I get less yawing and sliding too. This configuration seems to be the best way to deal with rough weather for me. If the engine died, it may not be worth trying to sail much though, maybe a sea anchor would be your best bet provided you have the running room.

If you were worried about excessive pitching, that could be a big problem. My Mac has only sailed coastal West Florida where the water is shallow and the waves are closer together but not as high as to ever think about pitchpoling (never been out in a hurricane though). With our waves during a big blow, I can't typically go as fast as you Frank. Exceeding hull speed as you are doing is not usually possible in those kinds of conditions around here unless you are surfing.. Deep water waves are much different. I think I am still only using around 5-10 HP to truck along at 4-5 kn. I'm sure Moe could calculate the precise number but my guess is you are still not using more than 10-15 HP in the 7-8 kn semi-displacement zone or maybe 15-25 HP in the 8-10 kn speeds. You really need to break into the planing speeds before you are using the upper half of a 50HP let alone 90HP IMO. I agree that currents can be a big factor, but they are just that, a factor...so you add or subtract it from your ground speed. Currents around here (out in the open) aren't all that much..maybe 1-3. If you are in certain tidal inlets of course, the water can get moving much faster and yes a bigger motor would be better for that but I believe you could still get by just fine with a 15HP motor. Big foot is better for the very slow speeds (like docking) but I'm not convinced there is much difference at higher speeds.

You do lose a lot of inertia in a Mac when you bash head on to a wave compared to similar sized boats of higher density (like my former keelboat for example) but I don't think its anything a 10-15HP motor couldn't handle. You are going to lose the inertia whether you have a 10 or a 90 horsie. The only reason you might lose a bit less with the 90 is because of the added mass.

[Frank C]

If I remember right, hull speed is closer to 6 kn in this boat.

Dimitri,
David Gerr is a contemporary nautical architect. Watch closely and you'll see occasional articles he writes on various topics for Sail & Sailing magazines. I found and adapted this stuff from the Potter Owners' website, where Gerr wrote the following description & justification for
Gerr's Modified Hull Speed Formula:

"If your speed is limited to the hull speed predicted by the formula Anthony Deane worked out in 1670 for British Men O'War, Hullspeed (knots)=1.34*(LWL^1/2), then you have a displacement hull.

"If your speed exceeds the theoretical speed for a displacement hull, you have a semi-displacement or planing hull ... A hull is planing when it is supported by the water flow under her hull. When this happens, she is displacing less water, and this will be reflected by the wake. Watch the stern wave. When the crest of the stern wave is aft of the transom, you are going faster than 'hull speed.' When the stern wave flattens out, you are planing."

The Mac's flat hull simply incurs less resistance than the 6.4 knot limit of a traditiional hull form. Gerr's formula shows that lower displacements permit higher speeds without actually planing. Even among non-planing boats, many can go faster than Deane's formula predicts. Most folks divide boats into two categories - planing vs. displacement, a difference that is visually obvious. But many small sailboats DO go faster than a displacement hull of similar LWL, without planing - semi-displacement hulls.

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Gerr's Formula:
Eq #1: D/L=(weight/2240)/(0.01 * LWL)^3 
Eq #2: S/L = 8.26/(D/L)^0.311 
Eq #3: Hullspeed = S/L * LWL^0.5 

Equation 3 is like the traditional hullspeed formula, but the constant is no longer 1.34. S/L ratio replaces Deane's constant, thereby accounting for water-line length AND displacement of the boat. Assuming that a 26X has LWL = 23, and weighs 4,700# under sail, then:

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D/L = 4700 / 2240 / (.23^3)  = 172
S/L = 8.26 / 172 ^ 0.311  = 1.666
1.666 x 23 ^ .5 = 7.99

Therefore: Gerr-factor for the 26X = 1.666 (not 1.34), and
the theoretical hullspeed of a 26X (displacing 4700#) is ~8 knots, w/o planing.

(If your Mac weighs less than 4700, hullspeed is proportionally faster.)

[Rolf]

MM and Dimitri, you are both correct when saying the boat can easily handle these rough conditions when sailing or motoring with a small outboard, FINS DOWN.

Bad mistake on my part to omit this detail. I was referring to no rudders, SLIGHT amount of cb down. My old 50 would handle these conditions COMFORTABLY with no ballast, and maintain close to 10 knots in the process.

My 90 does it with the ballast tank full and a much stabiler powerboat feel-- the bigger torque/propeller is responsible for this. You can't maintain 10 knots in rough (not gale) conditions with a 6 horse.

I'm just trying to enlighten people to the fact I think this boat has another dimension to it-- True or close to true power boat performance when equipped with a more powerful motor. I would never question people's own personal preferences or knowledge of the craft. Some amazing stuff people like MM are doing out there!

Rolf

[maddmike]

Frank,

In both the math & real world arena you are right on target for the M26X.

Rolf, I understand your position, but would like to make a couple of points.

In the conditions you described at the start, I would not even like trying to control a 282 Mako with twin 200hp. engines (a boat I have extensive experiences with as a day charter Captain in the Caribbean). Coming around Rams Head on the South/East side of St. John at least twice a week in the Maco (back from Norman Island), I sometimes experienced a beam sea in the conditions you describe and had to work the boat hard to maintain acceptable control (working both throddles & attack of angle to the waves). My horsepower was not the ket to a safe return. The same place & conditions in the MAC without sails required much more skill. With some sail area, the MAC became even more easy to work around Rams Head abeam the seas than the Maco with 400hp. While I know that many MAC owners do not have much experience using the sails & motor together, I believe it is very much in their own interest to do so. Understanding how to use the sails in advesrse conditions gives you a very important safety opiton. I believe that if folks spent the extra time learning how to do this, step by step, rather than expecting horsepower to make things safe, they would be better off. Balancing your skill sets between powering, powersailing, and sailing (something the MAC is great for).,might be the best approach to making what is often preceived as a dangerous situation into a fun motorsail. Thoughts? Maddmike

[RobertKing]

I have found that my hull speed is directionaly related to my age, much to my dismay.

[Frank C]

. . . While I know that many MAC owners do not have much experience using the sails & motor together, I believe it is very much in their own interest to do so. Understanding how to use the sails in advesrse conditions gives you a very important safety opiton. ... Thoughts? Maddmike

Thoughts --- me?
Actually, I understand your point, and agree completely. However, it's really tough for the average rec boater to gain enough of that practical experience. For me, flying sails in 25+ kn is frightening, especially when the wind's behind me. So ... this is an endorsement of your recommendation, plus my excuses for not accomplishing it.

I'm fortunate enough to get time on the water, but only occasionally. I thank my stars that it's usually on SF Bay where I'm likely to find brisk conditions that are really challenging (yet manageable) for me and the boat. I'm also more at risk to have severe conditions overtake me, but only rarely. No fool here, I check the forecasts before venturing into the center Bay and I approach center Bay from the south where it's easy to see trouble before getting into it - in which case I can remain in wind shadows south of the Bay Bridge, or turn tail back to the marina.

So, while endorsing your recommendation, I would need either of two circumstances to become competent for true motorsailing in severe conditions - even though I believe it WOULD INDEED be a better choice than brute horsepower. First, I could hire some experience to take me into the teeth of the Bay and teach me ... or just set (solo) sail out through the Gate & learn it ad hoc - probably what you did, but unlikely for me.

I agree that brute horsepower is a crutch for the novice rec sailor to enjoy moderate sailing, yet scoot from the real challenges. Time permitting, I'd sign up for a full bareboat course (maybe a half step between the other two) and grow into the confidence to fly sails in some severe conditions. That's for someday ... but for today I usually just settle for mediocre & enjoy what I know, plus whatever I can learn on my own.

It's akin to my golf game ... not enough time to devote two half-days each week to get good at it. But in the case of golf, not willing to be really bad at it, so I just don't play at all. Sailing's much better, since a couple of days each month provide challenge, plus learning, plus zen ... just gotta be sure the winds will be less than 20 kn & good to go.
And the 14" prop on a Suzuki 60 is my caddy!

[maddmike]

Frank,

I really can't argue the logic in your response. Also, I do not recommend anyone going beyond the gate to see if they can figure it out on their own. A charter sailing school would be helpful, but will not teach you much about how to handle a MAC powersailing in rough conditions. A Hunter, a CSY, anything else except the MAC which is a whole different animal unto itself. Next time the weather gets a little strong on the bay (not gale force, just a touch strong) maybe practice with a reefed main & 80% furled jib, while using the main sheet to steer. Do it close enough to homebase that you could drop the main, roll in the rest of the jib and get back in your slip with the motor (humbled, a bit of a mess, but home safe). Then should the wind Gods ever really try to ruin your day, you will have some experience under your belt; maybe just enough to turn what would be a real scare into an additional learning experience. This advise is really for anyone using a MAC where there is a chance of getting yourself in trouble by depending on just the engine. Maybe someone should try to organize some type of MAC bad weather powersailing course, as there seems to be enough folks (and boats) out there to make it worthwhile????

[Rolf]

MM,
Taking rough conditions on the beam, the one thought that comes across my head constantly is "what if the motor (or worse yet the steering!) puts out?" At 2500 rpm, I was burning a lot of extra fuel and knew a gas tank change was imminent. Never changed one so fast in my life! I kept imagining a heavily reefed main would have been added to my peace of mind for the motor conking out scenerio.

I usually only carry a hanked on genoa and jib in case of motor failure (leave boom/main at home or down below for family comfort with dodger/head high bimini), and can't imagine going up forward deck to mess with jib at that point. Don't have a furler or halyards led aft because I only trailersail(more stuff to set up!) Your explanation of throttle control and turning into and out of the swells as most important is dead on. I still think the ballasted boat with no fins with heavy wind and swell directly abreast is quite squirrly (harder to keep on course) with lower horses, due to the flat bottom and high freeboard.

MM, do you or anybody else here have any stories about the motor or steering cutting out in rough conditions? You sound too prepared with your multiple motors/sails for that to happen. Frank like your explanation about hull speed according to transom wake!

Rolf

[maddmike]

Your kidding, right Rolf?

Yes to be honest, sometimes I feel like about everything that could happen has happened at least once.

Caught on fire (once).

Broken rudder (3 times)

Broken rudder mount (lost count, until I went to the 3/8" aluminum).

Run out of gas (several times) once had to do a fuel drop from a bush plane (don't even ask how much).

Lost centerboard (twice).

De-masted (nope, but lost a forestay in a storm-thank God for the inner-forestay and staysail).

Ripped bottom end of engine off (once on the Honda, big $$ in the boonies).

Blown sails (once, 3DL Genoa).

Run aground (several times without damage).

boat adrift (twice).

Bad guys trying to get on board (twice)

Stolden tender (once, but got it back).

I have some suggestions on how you can work with sails without a boom & hanked on headsail that I will post nbefore the end of the day. Cheers, MM