Lord Nelson Victory Tug 11.5 m

[User_U]

Dear Forum,

we have launched with our partner a new Lord Nelson Victory Tug this summer. Does anybody know anything about the history of these boats?

Where to find their origin, some facts about the design or anything else would be great. We know really nothing (except how to biuldt.... )

The Boat made of a GRP-Hull with wood-epoxy-GRP - Superstructure, eqipped with an 100 HP-Engine...infact too small but ordered by the owner.

Some pictures and data sheets will be online the next days.

So far, best regards from Germany

Udo

[SubCarBuilder]

Sorry, I tried to help in the search the only thing listed is that the boats run on a six cylindre diesel engine, and that they are for sale everywhere for around $145 000

Sorry about not being much help.

[Tad]

Originally marketed by Lord Nelson Yachts in Seattle, Washington USA. Designed by Jim Backus, also in the Seattle area. I believe he has a website, but I can't find it at the moment.

Production started in 1984, and by 1990 about 75 boats had been delivered. The arrangement was revised in 1990, moving the galley to starboard from the original portside. Teak decks were eliminated at this time. Engine was 150 HP Cummins, fuel 250 gal., water 185. Design displacement was 20,500. Reported range was 1000 miles.

Tad

[User_U]

Thanks guys for the replies....maybe we can find some more information - I found James Backus, Independent Designer, Designer For Pearson, Robert Perry, Former President Westlawn in the internet - I think it's him.

maybe somebody could give a contact adress or any further information.

so far, thanks a lot for your help

Udo

[FAST FRED]

What gives you the impression the engine is too small?

A hull like that will cruise on about 25hp , it was never designed to yank water skiers !

FAST FRED

[Tad]

In June 2003, there was an advertisement in Passagemaker Magazine for a tractor tug/yacht by Jim Backus. The only contact information was a website, backusyachts.com, which is now gone. I recall looking at the site at the time, so it was up. Perhaps you can find it in some archive.

All the best, Tad

[User_U]

Fred - there are a couple of things you should mention about: the efficiency of a 5.5 m long propeller shaft with bearings, the load problem of the engine (why to drive a long distance with a diesel engine running 3.000 RPM to reach 8 Knots?), the installed propeller and so on....

greets from Hamburg, Udo

[Dutch Peter]

Originally Posted by User_U

Fred - there are a couple of things you should mention about: the efficiency of a 5.5 m long propeller shaft with bearings

You can take 1% losses for bearings on a shaft train, that's 1 HP your lossing.

Originally Posted by User_U

the load problem of the engine (why to drive a long distance with a diesel engine running 3.000 RPM to reach 8 Knots?), the installed propeller

The diesels I've seen, running on 80% load and around 1800 - 2000 RPM. So if you need 3000 RPM, maybe the reduction is wrong for the prop? Or the prop is wrong

Originally Posted by User_U

and so on....

What else is there?

[FAST FRED]

Most displacement boats are designed to travel at under hull speed .

Long range work is usually conducted at "Unity" the speed where skin friction is about equal to wave making resistance.

For most fat boats ( DL 3 -1 or 4-1) this is about the square root of the lwl.

With a 37 ft boat , you would be really lucky to have a 36 ft lwl, and a cruising speed of 6K.

Nothing wrong with the boat or drive shaft , only with an attempt to go 8K.

Yes 8K is 1.34 times the 6K , but thats for sail boats! not power boats.

The reason ,is as you have discovered is it takes flank speed and huge noise and fuel flow to do what the wind does at over 15K, produce hull speed.

Most cruisers are engined and proped for cruising at unity or 1.1 (6.6K) or if slipery enough at 1.2 ( 7.2K).The difference in fuel use will be GREAT at any attempt to go faster.

IF your not getting 6 to 6.5K at a nice quiet , 1800rpm or so , you may wish to try a better prop combination.

FAST FRED

[User_U]

Thanks guys for the replys!
Sure we know how to calculate and how to choose the right porpeller but for a tug boat like this an 100hp-Vetus-Engine should not be the right choice....an engine with a more effective power/RPM-ratio would be better, don't forget at the theoretical calculations the use of the boat in rivers with 4 up to 6 knots, the wind and so on.

Anyway - you helped with the information about the Designer Jim Backus and Lord Nelson Yachts in Seattle.

Best regards, Udo

[8knots]

On your next one look into the newer Westerbeke's I think they have the right idea in my book,at least for us slow boat guys. they have the following
80hp NA
110hp TA
120hp NA
170hp TA
All of them develop max hp @ 2500 turns or less. with a real sweetspot about 1800 rpm. reasonable power to weight ratios and low installed height.
just a tidbit for your next one! 8knots

[Portager]

I agree with both of you. 100 HP is plenty of power for operation in minimal current, but if the Tug is intended to operate in 4 to 6 knots of current, then I submit that a full displacement hull is the wrong hull form for this application. If the current is running at 6 knots it will take a lot of power and fuel to maintain 1 to 2 knots headway. This application would be a good use of a semi-displacement hull. The semi-displacement hull with 175 to 200 HP could do 8 to 10 knots and fuel would be significantly reduced.

Regards;
Mike Schooley

[Jim Backus]

The photographs Udo has shown are not of a Lord Nelson 37' Victory Tug. None were built in Germany. The design shown is by Dudley Dix, formerly of South Africa and now Virginia. While similar in profile, there are differences in the overall designs.

Most of the Victory Tugs had a 150 HP BMW engine standard. This was over sized for the design as it did not require more than fifty plus horsepower for anything it was intended to do. However, the builder was given a good price on the BMW so it was used without consulting me. With the stern designed as it was, full throttle produces about a three foot wake. But then the hull was never intended to exceed hull speed, which it did with full power. (No boat ever planned howver, as the hull could not break form the wave it was creating.)

I did do a modern tractor tug and am in the middle of developing a sixty foot version. There are no plans for viewing at this time. To reach me, use jimbackus@sbcglobal.net. My web site is www.jimbackus.net