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Going upstream on the Cumberland from a certain point is a matter of motor only with no real opportunity to sail in the twisting narrow channel, SO i wonder how stable the X with Merc 50 will be if the mast is left in trailering position on its crutch and bow pulpit, with the furler on top.
Any experience this way? How about with ballast OUT or ballast IN. ?

Without any detailed analysis, the lower your center of gravity (CG), the higher your stability.

Lowering the mast to trailering position will have a net effect of lowering the CG, and I believe moving it aft a bit. Overall, this effect will be very minimal. Likewise regarding ballast - if she is stable unballasted with the mast up, she will be with it down.

The only negative I would see would be if you were already overloaded aft and carrying the mast this way just sank the stern further.

Potentially more important though, is what carrying the mast (and furler, and shrouds, and ...) on the crutch does to your visibility as you are transiting a narrow, twisty channel. Unless there are low bridges, from a viewpoint of safe navigation, you're probably better off having the mast up and a much clearer field of view.

- AndyS

mast in trailering position means you have the center of gravity where it belongs as the mast is exactly over the hull. drawback is that you have the shrouds and stays cluttering the cockpit and deck and you will surely bang your head against the mast ! visibility is not offended but place to move will be. i made some river and canal trips with the mast in the bow pulpit as there were many bridges. for longer transitions have the mast up or in the trailer position. only lowering the mast (and leaving it in it's step on the cabin top) means it will stick out 12 ft at the stern and you will probably bang it against a lock wall or a piling. the mast will also push your stern down as mentioend before. regarding the ballast: do as everytime, go without if you want, but fill it when wind or water get rough.

Are there other sailing opportunities on the trip? If not many, just leave the mast home. We go out mastless often. It takes no longer to take the mast off at home and leave it setting on saw horses than it does to raise it at the launch. With the mast in the trailering position you undo 5 ring dings and the whole thing is free (7 if you leave you baby stays attached all the time like I do). Don't forget to free the furling line and the sheets if you have a furling head sail. Undo the lower pins at the chainplates so you don't mess up your rig settings. With two people, one on a step ladder at the bow, you can lift the mast off easily. Just take care that you don't put any weight on the spreaders during the process.

I have a step by step procedure for this process in our setup and teardown procedures at my web site.

http://www.ddunn.org/Boat%20Procedures.pdf

It's on page 4.

Going out this way make launching a pleasure. Pull up at the ramp, take off the tiedown strap, toss out the fenders and dock lines, back her in. You'll feel like one of those normal boats.

I have sometimes shipped the mast if I have needed to get 60 or 70 miles in a hurry. I have not noticed any negative points. Wothout ballast and the extra knot of speed is nice.....however you will be out in the weather ,so it is a tradeoff, The one configuration I generally dont do at high speed is mast still at the foot, with it riding in the pedestal cradle...probably is perfectly safe, I just dont do it, I think that is the configuration that I lost my mast mount antennas in both times. since the mast has such a greater amount to flex at the top.

darren

One thing left unmentioned so far ... the erect mast damps rolling motions. This can be valuable in swells, where the risk of bridges and overhead wires is obviously minimal. On the Cumberland River you may have both overhead impediments, and unless it presents you with rapids, maybe roll-damping is a non-issue.

Regarding ballast, as long as the crew size is 4 or less, I prefer ballast empty. The boat is amply stable, lighter and more maneuverable, and going upstream I'd think that "empty" is a no-brainer.

If you're mainly doing a channel cruise, with very little opportunity to enjoy sailing, then Duane is spot on - leave the mast behind. Whether on the pulpit or on the mast step, the horizontal mast and shrouds will definitely be "in the way" making for a less enjoyable cruise. I even hate to work on the trailered boat when the mast is down - try it and you'll see how much worse it might crimp your style on the water.

Frank C wrote:One thing left unmentioned so far ... the erect mast damps rolling motions.

I don't think it damps the motion as much as it increases the period of the "Pendulum". You will get just as much or more motion with the mast up. It just won't be as fast. A longer pendulum swings slower.

--Mark

True enough ... it slows down the roll rate, perhaps making the motion less uncomfortable. And, it surely may enlongate the actual roll arc in some conditions.

My thought, though, maybe the mast period would enable the hull to simply not respond, or not roll in short choppy conditions - rather plowing through??

The great mathematician John Von Neumann was consulted by a group who was building a rocket ship to send into outer space. When he saw the incomplete structure, he asked, "Where did you get the plans for this ship?"
He was told, "We have our own staff of engineers."
He disdainfully replied: "Engineers! Why, I have complete sewn up the whole mathematical theory of rocketry. See my paper of 1952."

Well, the group consulted the 1952 paper, completely scrapped their 10 million dollar structure, and rebuilt the rocket exactly according to Von Neumann's plans. The minute they launched it, the entire structure blew up. They angrily called Von Neumann back and said: "We followed your instructions to the letter. Yet when we started it, it blew up! Why?"
Von Neumann replied, "Ah, yes; that is technically known as the blow-up problem - I treated that in my paper of 1954."

Seems we have a lot of engineers on the board

And it seems, according to the moral of the story, we should listen to our engineers the way the rocket builders should've listened to theirs...

--
Moe

Dude Im just a simple trucker, all the engineer speak makes me cross eyed.

Just kidding I enjoy knowing why glass is transparent and I enjoy poking fun at people I barely know.

Luv them engineers.

well thank you all for the great tips... here is my reaction so far, ....
will just leave the mast in trailer position as it sits, rather than ever take the time to remove. I have the spreaders out tof their sockets anyway -(quick pins) , against the mast in a pair-of-PVC tubes arrangement, and there is only one place i have to step carefully to avoid the shrouds and genoa sheets on each side of the cabin-top decks. The mast provides a stable hand-steady when going forward, (thanks in part to my PVC "stovepipe" mast-step support) and isn't really so much in the way, as i have learned to get around it all the time as i work on the boat at home. Also, i use it like a tent ridge-pole for draping bungee'd tarps over the companionway and cockpit. The boat would be nekkid to me without it. Consider also the chances to get shrouds crossed with sheets, and so forth on removal and replacement, besides having to enlist help (though i am able to do it alone if careful by rolling it off the crutch onto the ground behind the boat.)

Thats gotta be a joke......

No engineer I know is going to scrap his work for the ideas of a mathmatician, computer scientists, and some physicists.... (Von Neumans major fields)

We Very rarely change....continually work on minor improvements...as well as major. we are hypercritical.....take little on faith...and measure everything.... Just like great machinists and mechanics.

I can show you work from the 1870' where engineers and mechanics were absolutely sure man would successfully attain powered flight. and they were scoffed at by the physicists, mathmaticians and intelligentsia of the day...


It took a couple of basicly fearless bicyle mechanics....who really had no provisions for surviving a real crash to finally sway the world. In fact, the wrights are most famous in the technical community for their documented studies of drag and aerodymanics and solving the problem of control surfaces...... Patents they diligently protected for over 40 years...

Feel free to pick out and pick on wrong engineers.... thats the thing we have in common with docs on occasion, people die, we get sued.....

Definitiions of engineers

Aerospace engineers....make delivery systems
Electrical engineers make targeting systems
mechanical engineers make delivery systems and targets
Civil engineers Make targets.....
Chemical engineers and Physicists...... welll........they make things that go bang really loudly.

Regarding stability and roll with the mast up, I agree, it is lessened this way. The mast up is absolutely critical(I believe) for those of us with heavier motors -->300lbs. Fully loaded with another 100lbs of gas tanks aft and 3 total passengers aft, the boat is back heavy, which is okay for preventing capsizes(ballast empty) but makes for an uncomfortable ride in a slight chop as the bow light boat will skip/pound if motoring faster than 13 knots. For these conditions, I load everything underneath forward and luckily often the wife and kid will nap in vee berth -- Perfect balance! I can't imagine not having mast up and forwrd there, although I've never powered with it removed -- just down and in trailer position.
Rolf

Moe wrote:And it seems, according to the moral of the story, we should listen to our engineers the way the rocket builders should've listened to theirs...

--
Moe

Lol- In my line of work we deal with engineers from time to time (aircraft issues for critical systems and failures)... I take the moral of the story to listen to the engineers, then question them on everything.

Jeff S