Bow thruster - is it a plus or minus?
- Thread starter Scott T-Bird
- Start date
You will LOVE it if you have it. Like electric winches or anchor windless. My boat handles well at the dock, but handles GREAT with the bow thruster. It can spin in (near) its own length, with assist from prop walk.
Would you buy a TV without a remote? No because they don’t cost extra, but if it made the TV cost double you might rationalize the need to get up from your chair to change channels. All this other stuff about maintenance is rationalization, IMHO. If you’re a racer the extra drag might be a factor, but for cruising and daysailing the effects are negligible.
Would you buy a TV without a remote? No because they don’t cost extra, but if it made the TV cost double you might rationalize the need to get up from your chair to change channels. All this other stuff about maintenance is rationalization, IMHO. If you’re a racer the extra drag might be a factor, but for cruising and daysailing the effects are negligible.
Interesting observation. Probably true.
Folks who have thrusters tend to use them predominantly when leaving a dock when there is little/no water flowing past the rudder. Of course there are work-arounds which are pretty simple but it’s amazing watching people confuse full throttle with neutral.
I have a Hunter 30 and a very tight slip. I’d love the piece of mind while single handed having a thruster but I wouldn’t add one myself due to the maintenance and space taken up for it.
They do not require any maintenance other than inspecting the zinc during bottom cleaning and inspection when out of the water for bottom cleaning. Surprisingly, it also does not take up much space as shown in the attached photo.
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Use of a bow thruster kinda sounds like the age ole argument of motorcycles with anti lock brakes. Do thruster's effect flow over the surface of the hull of course they do, to what effect, now that is a good question. I know on our hull the forward side of the 6" tube opening is built up like a smooth upward curve to direct flow over the hole with minimal disturbance. I have read testimony by one who has added a thruster to a boat that they have had for a few years and stated they saw no noticeable loss in performance.
Taken from an article in Cruising World, "You'd think that having a tunnel bisecting the bow below the waterline would surely lead to increased drag when you're sailing or powering at speed. But this can be minimized, provided that a small lip is faired into the leading edges of where the tunnel meets the hull and that a depression is created along the trailing edges. These divert the water away from the tunnel port, resulting only in an almost imperceptible increase in drag."
Taken from an article in Cruising World, "You'd think that having a tunnel bisecting the bow below the waterline would surely lead to increased drag when you're sailing or powering at speed. But this can be minimized, provided that a small lip is faired into the leading edges of where the tunnel meets the hull and that a depression is created along the trailing edges. These divert the water away from the tunnel port, resulting only in an almost imperceptible increase in drag."
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After reading the collective wisdom, if I was considering 2 boats that were in all other respects equal, including price, I would buy the one with the bow thruster. I would not include the bow thruster as a feature or detractor until I was convinced the boats were otherwise equal.
Now if I was purchasing a boat with a full keel or some 45+ foot boat, a bow thruster would be a bigger factor.
Now if I was purchasing a boat with a full keel or some 45+ foot boat, a bow thruster would be a bigger factor.
it's all about the details,
long keel, 2 bladed prop, extra heavy built, short waterline for the weight, lake michigan phrf 159. yep, aeolus on paper is the slowest boat amongst you all. then we have these discussion about one item or another and ask "will it impede my sailing?'. the answer is always about the same. 'no, we can't tell any difference'. i've been on ships both with and without thrusters. yepper, thrusters help maneuvering at the dock. until, you really need them in a blow, is the old joke.
But you all the clutter up these nice boats with 20 or more of these items that "make no difference" and what do you have? a motor sailor that will reach nicely and i sail my old slow vessel right past you. he he! that's because i have rigged aeolus with none of those work saving options that collectively make a boat a "pig". my attention to dynamic sailing is over the top compared to most of you.
it is just what i prefer, nothing more.
there is a sabre 45 owned by the guy that ran PJ's back when they built all those great sailing machines. he has sailed all over the globe. he knows what he's doing. he's an old friend. i very much enjoy passing him on all points of sail with the old alden as we exchange a smile and a wave.
sailing a vessel that has been maximized for sailing, not docking or anchoring, has a great feel about it. i just love that feel.
example: flying a small jib when it's blowing 30/35 has a better feel than a half rolled up big jib. it performs better.
so it's choices, nothing more. 20, make the vessel sail better choices add up to a much better sailing vessel. 20, i want to work less choices usually make the boat way less of a dynamic sailor.
i promise to wave as i sail by, he he he.
i just love the sailing part!
and to be honest, aeolus is very easy to dock. my youngest started docking the boat when she was seven. the older kids were better with the ropes and fenders.
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30 years ago when bow thrusters were just coming out, Shannon sailed two identical boats against each other - one with a thruster, one without. They couldn't measure any speed difference which surprised them. The marine architect told me that it is likely because the hole is perpendicular to the water flow and open at both ends. It is filled with water at the same pressure as the surrounding water. There's no "bump".
If the hole comes partially out of the water with each wave then it will create more drag. This is a problem with powerboats but doesn't happen on sailboats if the bow thruster was installed deep enough. And most traditional sailboat hulls (like the OP's) have long deep bows that make it easy to place a bow thruster deep enough very near the bow. The top of the bow thruster tunnel has to at least one tunnel diameter below the water - deeper is better. Obviously, in rough conditions, the bow thruster hole may come out of the water in waves but by then it's windy enough that a little extra drag won't be noticeable.
If bow thrusters really did create serious drag, you'd see many more retractable thrusters or thrusters with doors on luxury sailboats like Oysters where people pay astonishing sums for a carbon fiber mast upgrade but stick with regular tunnel thrusters. On a very large boat, the bow also get's quite wide which means a very long tunnel. Here a retractable thruster can be less expensive to build.
If you are concerned about sailing performance from drag, having a folding or feathering prop will make a much bigger difference.
If the hole comes partially out of the water with each wave then it will create more drag. This is a problem with powerboats but doesn't happen on sailboats if the bow thruster was installed deep enough. And most traditional sailboat hulls (like the OP's) have long deep bows that make it easy to place a bow thruster deep enough very near the bow. The top of the bow thruster tunnel has to at least one tunnel diameter below the water - deeper is better. Obviously, in rough conditions, the bow thruster hole may come out of the water in waves but by then it's windy enough that a little extra drag won't be noticeable.
If bow thrusters really did create serious drag, you'd see many more retractable thrusters or thrusters with doors on luxury sailboats like Oysters where people pay astonishing sums for a carbon fiber mast upgrade but stick with regular tunnel thrusters. On a very large boat, the bow also get's quite wide which means a very long tunnel. Here a retractable thruster can be less expensive to build.
If you are concerned about sailing performance from drag, having a folding or feathering prop will make a much bigger difference.
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If you're going to race the boat, yes every little bit may help. But, if you're like me and load the boat for the weekend or week-long trips with 50 gal's water in the bow tank, 25 gal's desiel, 25 gal. holding tank filling up, add 4 6v batteries for power, load in cooler full of ice and beer, fridge full to the brim, drag a dinghy out the back, etc....... I wouldn't worry about the miniscule affect the thruster may have. Buy the boat based on whether the rest of the boat fits you. Btw, I can still get 6.5 knots under sail with all of the above ( sans thruster) . 6.64 knots I doubt I would notice.
We don't have one, nor need one, as our boat is only 30 feet. But I always imagined that with the rather intense fouling (barnacles mainly, slime secondarily) we get in the upper Chesapeake, the big maintenance issue would be cleaning off the fouling on the propeller. If they get crusted up with barnacles, doesn't that cause problems?
georgian bay is my favorite place to sail on the globe. have sailed over there many summers. while there, the challenges to sail a vessel from A to B are a delight. i will say that most sailboats i saw over there were motoring so much of the time. you know, using their boats like a motorsailor. rarely if ever would they tack upwind through a channel. rarely if ever would they fly a spinnaker or staysails through those beautiful islands. it's not just a racing thing really, it's a sailing thing. it's just choices. do you want to sail 95% of the time, or like most vessels with a mast sticking up in a maze of wonderment actually motor more than sail.
choices, none are better that the other. BUT, if you use a boat for sailing , performance counts allot. if you use a boat to motor sail, well, 'turn on the iron jib'
@jon hansen my plan for this year was to race the Port Huron to Mackinaw with the crew and then meet the admiral on the island or Mac City, trade the crew for my lovely wife and then head into Georgian Bay, but we are not quite sure what is going to happen to the race this year.
In discussions many feel that there will be a race, it just won't be official....
I have had Georgian bay on my list even before we had a boat to get there, as a youngster we vacationed several times on the Bruce Peninsula, beautiful country that is for sure, its been a while since I looked at any charts but I know there are many anchorages along the shores, would love to pull into Kilarny or Owen Sound and have a bite, they are sweet stopping places and would love to see them as approached from the bay side of things.
In discussions many feel that there will be a race, it just won't be official....
I have had Georgian bay on my list even before we had a boat to get there, as a youngster we vacationed several times on the Bruce Peninsula, beautiful country that is for sure, its been a while since I looked at any charts but I know there are many anchorages along the shores, would love to pull into Kilarny or Owen Sound and have a bite, they are sweet stopping places and would love to see them as approached from the bay side of things.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,790
DayDreamer.... Once the Borders open, why not make your day dreams real - this year.
@jssailem, We are currently having those discussions, the problem being is whether the admiral can string enough time off to achieve a fruitful trip, but we are working on it. A plan which we have discussed is have my sons with me to sail up to Rogers City MI, cruise around that area for a week or so, then have her drive up to Rogers City meet me there, let the boys take the car home and then jump across to the bay. Kinda like we were talking about after the Mac race.
I guess that is what you call major topic drift, from Thruster to Georgian Bay, sorry @Scott T-Bird
I guess that is what you call major topic drift, from Thruster to Georgian Bay, sorry @Scott T-Bird
To thrust, or not to thrust (your bow), that is the question?
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,790
“Whether 'tis nobler in the mind to Sail
The seas of outrageous fortune,
Or to take the Thruster against a sea of troubles,
And by opposing end them?”
Sorry William.. I was moved to respond.... perhaps. “The better part of valor is discretion”
With that I shall take my leave... “Parting is such sweet sorrow that I shall say goodnight till it be morrow.”
The way I see it, its like buying a house that already has a pool in the back yard. Its really cool to have but there is no way you would ever actually install one yourself.