Trawler Ideas

Discussion in 'Powerboats' started by Fish Catcher, Nov 22, 2014.

  1. WestVanHan
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    WestVanHan Not a Senior Member

    My 50' non-trawler I get about 3 nmpg at about 7 knots,at 9 knots it's about 2nmpg. A friend with a 40'-ish trawler is quite annoyed that he gets worse mpg at 7 then what I do at 9.

    It's all downhill from there, but the mpg-once she pops up on plane-at 12 to 30 knots is the same.
     
  2. Fish Catcher
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    Fish Catcher Junior Member

    Steve,
    Exactly and well put !!
    To me Fuel erconomy or as I say a fuel sipper is very important for the following reasons.
    The river systems ( on the great loop ) have some pretty big windows for fuel stops.
    Several are uncertain as one gentleman passed away and last I knew his daughter was trying to keep it going but time will tell if she has the time and dersire.

    Another fuel stop is loosing water from what I have heard, something about the dredging and goverment not upkeeping as well as they once did.

    All this means......you need a boat that can run at a cruising speed of 7 or 8 knots for hours and hours of time and burning no more then around 2gph....
    With this you must also be able to hold larger fuel tank or tanks (1000) gal maybe so you can comfortly run between stops and chose where you do purchase fuel.

    This is what I mean as a fuel sipper.........distance is more important then speed
    Jim
     
  3. Fish Catcher
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    Fish Catcher Junior Member

    Whats the fuel burn during this 2 and 3 nmpg ?
     
  4. Fish Catcher
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    Fish Catcher Junior Member

    I have looked at many cats from the pilot house type to the most outragious looking ones and I just do not see me in one. Something about a trawler or tug just draws me in. However I have hadf a custom coastal cruiser gety my attention before.
     
  5. Steve W
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    Steve W Senior Member

    I did a part of the loop last summer (2013) while delivering my old, mastless Gemini catamaran home from Connecticut to Duluth, a distance of about 1500 miles. We were only able to cruise at 5.5 to 6.5 knots with a single 9.9 Yamaha high thrust outboard but we averaged about 7.5 statute mpg so had pretty good range from the 2 x 12gal tanks plus we carried 2x 6 gal gas cans but only needed them once on Georgian bay so, no range problems on the northern part. I would love to do the entire loop with a boat that could cruise at 8k+, not interested in 20k at all. Interestingly, we had the motor mounted on the factory retractable bucket in the center of the aft beam with remotes and steering with the rudders, worked great and really did not suffer at all from the cavitation i hear people talk about but, since we did not have the sailing option i mounted an identical motor on a retractable bracket on the port transom and wherever possible we alternated which motor we ran daily so I was able to verify that when out in open water and not maneuvering there was no noticeable difference with how the boat tracked with the offset motor which confirmed my suspicion that with a powercat, running on one engine with the other prop feathered would be a very viable means of achieving good economy as well as extending engine life.
    It seems to me that the typical trawler yacht has a single diesel and twins are the exception but even those with twins end up with bow or stern thrusters or both so I expect that with a monohull, the spacing of the props are probably not far enough apart to overcome the windage. They install thrusters every winter at the marina i sometimes do large composites projects for and im increasingly seeing stern thrusters.
    The wide spacing of a Cats engines eliminates this need. Im not sure exactly the size and budget you feel you need but you would get a lot of accomodations in a 42 ft powercat and only require 60 - 100hp per side so running either 1 or both engine you are going to get good range and i would expect such a craft to cruise very economically at 8-10k and run up to maybe 18 if needed. I personally don't like the styling of most of the offerings out there except Peter Bradys boats and a few others so a semi custom design is the way to go for me. Things i like are covered side decks and cockpit,(I don't want to be in the sun unless I choose to be) an aft cockpit large enough to carry the rib without the need for davits, a large upper boat deck to carry light boats such as kayaks, sups etc. A head accessible from the cockpit, Household propane appliances in the galley which are very safe on a cat when everything is on the bridgedeck and trawler styling in profile.

    Steve.
     
  6. WestVanHan
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    WestVanHan Not a Senior Member

    You work it backwards from the speed,so about 2.4 gph at about 7 knots and about 4gph at about 9 or so.

    I think in km and litres and Imperial gallons so converting this back in my head to US gals and nm,it's fairly close.

    I think at 7 knots I can do about 2200 km which is about 1400 stat. miles.

    From about 14 to 30 knots my range is about 275 sm

    It's something like that-I haven't measured exactly in years...fuel cost when running 80-100 hours a year is negligible.
     
  7. Steve W
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    Steve W Senior Member

    WVH, i think the majority of people use their boat like you so fuel consumption is not so much of an issue, but if a guy was to do the loop you could potentially be doing up to 7000 miles with side trips and that takes a hell of a lot of fuel and the extra cost of diesel over gas is an extra insult. So, by default a trawler is going to be diesel so you had better be getting decent mpg.

    Steve.
     
  8. WestVanHan
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    WestVanHan Not a Senior Member

    OK so 7000 miles.Divvy by say 2 mpg= 3500 gallons.

    What is it..$2.50 US a gallon? Lets go up and say $3 a gallon.
    That's $10.5k in fuel, at 3mpg it's $7k... $3k difference is peanuts when the 49' boat he likes is $800k:
    -what if it needs to be hauled and have the bottom done? $5k?
    -how many nights spent at a marina at a couple hundred per night?
    -the radar stops working- $7k.
    -hits a log-diver + prop repair+ couple days at a marina- $1500? Tow?
    -how much is insurance?
    -etc.

    The 49 NT he's looking at, I'd be very surprised if they get more than 2 mpg at 7 knots.
     
  9. Steve W
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    Steve W Senior Member


    Cant argue with any of that, i always tend to think of this sort of thing from the point of view of someone (me) who cant spend that kind of money. I value efficiency in everything, boats included and I cant help but think that 5mpg or more should be possible with a powercat.

    Steve.
     
  10. Fish Catcher
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    Fish Catcher Junior Member


    The funny thing keeps coming into play within this fuel consumption topic.
    Price of such said vessel as if this factors into a desired fuel consumption.
    If I pay 200 dollars or 2.2 million dollars for any vessel, how does this matter when talking fuel consumption ?

    If I run a 16 foot with an out board I want to match the best fit in an outboard so as to be able to have More then Enough fuel to make it to "MY" desired fuel stop within the main fuel tank.......so if I run a 49 or 64 foot trawler I still want to match the engine with tank capacity so as to make MY desired fuel stop and not have to "order a tanker" full of diesel fuel and pay a high premium delivery price. They also only do this at certain stops and are just about all diesel now and NO gasoline.......

    OBTW the NT 49 burns about......29-30 gal at 16 to 17 knts...........2 to 3 gal at 7 to 8 kts and 1 to 2 gal at 6 to 7 knts

    I used to be all fired up about higher speed and getting there faster and so on. Then it hit me.....I have to fill up more and more and more. Not all higher running engines do well at a constant slow speed over and over and day in and out.

    It takes at least ONE full year to complete the loop and more then likely.....longer.....
    Thats running your boat a tad more then the local boater.
    I am NOT poverty minded.....I just want to fill up when I desire and not have to stop at any old fuel stop because I burn to much fuel.....its not about the MoNeY........its about choice

    I hope this does not sound like I am sounding off. I sure am not trying to but I am trying to make things crystal clear.....
    Have a great week end
    Jim
     
  11. Fish Catcher
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    Fish Catcher Junior Member

    Steve W
    One day you should do the complete loop and take your time and enjoy it. Peopel are so differtent acting along the loop. ( for the most part )You always find some meat head every where you go. lol

    I see more and more boats being fitted with bow and even stern thrusters right from the factory. I beleive it is because more people are getting fitted with larger boats and marina's are feeling smaller and smaller do to all the extra boats. People get nervous when docking or leaving the marinas and face it too many people do not have the training to handle a single screrw with precise maneuverability. Hence the bow thruster and a stern thruster also aids in docking and locking....

    Now I have seen that alot of folks simply do not have the cordination or patience to dock or lock via twins either. For some reason they simply cant get the right formula ( lol ) when it comes to one in reverse and one in forward.....tooo much gas....ohhhhhh crap ity turned this way and here comes the docked pretty boat again at me. rotfl......

    I had thoughts origionally in doing the loop in a 37 to 40 foot aluminum pilot house offshore boat with twin outboards and a kicker but.............it would be great for me and a couple fishen buddies.......it lacks in the home like feel that the girls want........you know what they say....if mama aint happy..............well you know !! just teasingh some, I think
    Have a great week end
    Jim
     
  12. Steve W
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    Steve W Senior Member

    Hi Jim, yes, I would like to do the complete loop one day but im not sure what I would choose for the trip, the Gemini as a powerboat was pretty darn good actually but too slow, and even though the outboards were small at only 10hp they were not short of power, just a short boat with fat hulls so even with more hp we only gained a little for more fuel so no more range. With a properly designed displacement powercat you need some length and slim hulls then you can have a higher cruising speed on smaller engines and better economy/range than any single hull craft of the same length.
    You have pointed out what i find unappealing about trawler or tug style boats and that is that all the single engine boats out there have a slower cruise speed than i would like but anything with twins always seem to be built to be able to do mid teens, which, by default means they will have engines too large to be efficient at the low economical cruise speeds needed for range, and, as you have pointed out the engines have a reduced lifespan when run a lot at those speeds. This is why Robert Bebbes Passagemakers used a single engine of low hp running in their happy rpm, that's how you get range but they cruised at 7 1/2 knot for weeks on end but at wot they would only get maybe another knot or so at a lot more fuel burn. The displacement powercat is the only way around this as far as i know.

    Steve.
     
  13. WestVanHan
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    WestVanHan Not a Senior Member

    That's about what I burn at that speed,however she's up on full plane and will keep the .7 mpg all the way up to 30 knots.


    Jim,doesn't sound to me like you're sounding off.
    I'm on the British Columbia coast:fuel stops are very few and very far between.
    Tides are usually 5-7 knots,and in areas they are 13 -18 knots. Slack tide on the big inlets and in many areas can be only 15 minutes.
    So with a 7 knot boat you spend a lot of time waiting for tides to change,or need to get up (a good chance of being hung over) at ungodly hours to go places.

    So for me,economical cruising with the ability to ignore all but the most wild tides.
     

  14. Fish Catcher
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    Fish Catcher Junior Member

    WestVanHan,
    Thanks and yea tides and current to factor in a lot more then some give mind too.
    I wish more companies built tug like boats. I like the lord nelson tugs alot but most werre all singler screw. There were a couple built with twins buty for the most part do not come up for sale but I did fgind one. A 49 footer but it is across the ocean and that opensd up all kinds of new doors to have to try and walk through.

    We dont like all the fancy (rich) looking stuff but I do like new boats. One day I shall find ours too.
    Have a great week
    Jim
     
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