Cruiser vs. Trawler - how to decide?

[MarkJ]

Fuel Range = The total for the whole trip out, there and back.

Florida fuel prices stupidly low. Bahamas Ouch!!


A full displacement vessel may have really quite small engines, say 200hp, but the equivalent size planing boat may need 2 x 750hp. Disregarding fuel burn, just the cost of the engines is huge compared to the little 200hps.

So a full displacement may be much more economical that you think.

[Cadence]

Originally Posted by fargo007

Hi,

The wife and I are looking at different types of boats, and we sort of find some overlap between what people call a trawler and a "cruiser."

I understand the displacement hull vs. planing, but when both are diesel the fuel burn seems to shake out reasonable close.

We want a solid boat with diesel motor(s) that sleeps us and a guest couple that we can make single runs between fuel ups of around 150nm absolute max (and that's padded a LOT). Mostly coastal, keys, and bahamas stuff. Overall cost of the vessel matters more than fuel economy or speed of travel.

I can find lots that we can afford in both of these worlds, but what am I missing here in the decision process?

Or am I just hung up on the cruiser/trawler monikers?

Thanks, and happy to have joined. A lot of good info here.

It is semantics. The each his own description. Mine is a trawler is displacement, swinging a big wheel with a diesel sipping engine. JMHO

[fargo007]

I really do like the idea of a motorsailer in this respect but it looks like you have to go way up in cost to get into one that isn't almost as old as I am.

Something like a PDQ Capella.

[donradcliffe]

If the stern of the boat is squared off, that's a semi displacement boat. If the stern looks more like a sailboat, it is a full displacement boat. The squared off stern makes it possible to plane if you apply enough power, but at the cost of higher drag at low speeds (my science fair project).

A 'trawler' like a GB has a semi-displacement hull but will not plane--the worst of both worlds.

A single engine boat will be more efficient, but will take more skill to maneuver without the complexity of a bow thruster.

A fast cruiser will not have much range at speed, but if you are short of fuel you can double or triple your range by slowing down to trawler speeds.

Beyond the Hype: Pod Drives | Yachting Magazine

[Colin A]

While currently a little boat owner I spend a fair amount of time on motor yacht and some LSD (long slow distance) boats for work. Really for what your talking about I tend to see more bang for your buck out of motor yachts but it will cost you more not just in fuel but maintenance on the bigger engines. But if you can get a good deal on one you tend to get more space and have more choices as they built more motor yachts/ cruisers then LSD boats. I have also found it surprising how close to a displacement hull fuel consumption some of the planning hulls can get when run slow not the same mind you but closer then I would have thought.

[boatpoker]

Originally Posted by donradcliffe

If the stern of the boat is squared off, that's a semi displacement boat.

Not quite... you don't get much more displacement than this

[Olddave]

It is worth considering motion when deciding between cruiser and trawler. Hull form/shape dictates how the boat rolls and obviously a chine boat will roll less at anchor and underway. This might be important to your wife or guests.
I am old school and absolutely love travelling in the classic double ended trawlers that started all the hype. They are awesome sea boats but do roll enough to make people sea sick. Note how many are fitted with stabilisers. Just beautiful boats though.
Chine boats will likely pound more when going to windward and I find that more uncomfortable than rolling. Fast chine boats will use more fuel. Some will use enough to wipe the smile off your face! Slowing down will use less. I operated a 23m planning hull with 1200hp each side & that burned 350 litres per hour when it got wound up, at 20 knots.
Dave

[TeddyDiver]

Originally Posted by donradcliffe

If the stern of the boat is squared off, that's a semi displacement boat.

Not..
For those interested google for "buttock angle"

BR Teddy

[Cheechako]

A Trawler is not designed to plane. The hull shape is different and the Trawler may even have some ballast in the keel. As such it is much lower Horsepower.
A cruiser run at displacement speeds may not burn much more fuel at all, but it will drink fuel fast if you plane it.
The planing cruiser may be a bit less rolly in some conditions as it's often built with flat wide aft sections. Often a Trawler may carry the traditional hull shape further aft without those flat sections. There are many different designs though and this is not necessarily 100% true.
Either boat with a dual engine setup has some redundancy if one engine quits enroute. If a single engine trawler quits, "you aint goin nowhere" until you get it running.
Realistically a sailboat motors as well as a trawler and has the option of sailing. However the sailboat often has a much different feel than a trawler. The Trawler or cruiser having nice open light living space that many sailboats don't have.
A Trawler with a squared off stern just means the designer is trying to deal with eliminating so much rolling in a seaway.

[darylat8750]

Comfortable roll characteristics are more complicated than hard chine or soft. The rate of acceleration of the rate of roll is a very large factor in comfort. I have a friend with boat that in a beam sea rolls to a certain point then very abruptly changes direction. It is absolutely miserable in 4ft. beam seas. My trawler is smaller and also has hard chines but has a much more pleasant motion and it takes a smaller course change to soften the roll to something that most folks can live with.

[Cadence]

Originally Posted by boatpoker

Not quite... you don't get much more displacement than this

You beat me to it.

[a64pilot]

Another thing, while it is true that if you bring a big motored Cruiser back close to idle, you will greatly increase the range, Diesels don't like to be run that way, they don't get up to full operating temp and slobber, dirty up the oil fast and can glaze cylinder walls.
Price engine parts for a Big Detroit Diesel, how much oil does it hold, coolant etc. operating costs are higher than for it's little Brother.
They are HUGE and you lose lots of room to those big things, But you do have to love the sound

Don't buy a planing boat to run it just over idle for extended times, you won't be happy.

I just remembered, Why not just buy a Cat, apparently they motor everywhere they go apparently

All joking aside a Cat does seem to have most of the advantages of a Trawler, plus being really good at anchor?

[markpierce]

Square-sterned, displacement-hull trawler:

[Chuck Hawley]

Originally Posted by fargo007

It's interesting that a planing hull actually has its best fuel economy per mile at higher speed. The numbers are totally different than a vehicle. You have to speed up to get the best mileage. I take the point that weather and conditions each have a vote here too.

Most of our journeys are going to be "let's get there safely and as quickly as reasonably possible, then dig in and chill for quite a while."

I don't think a 7 knot boat shows me a whole lot in this respect. I could do at least as well under sail.

When Powerboat Reports was still being published, I used to create fuel consumption curves for many of their test boats. Inevitably, there was a sweet spot that I could call a "slow plane" where the range was maximized, which frequently was around 3000 rpm for outboard powered boats, and less with inboard boats and diesels (of course).

One thought on your decision process is that there are a lot of faster boats that just aren't comfortable going the speeds that they are theoretically capable of. Yes, it tops out at 25 knots, but unless it's early in the morning on inland water, you just never get a chance to experience this.

I would look for something with a reasonably long waterline and an efficient hull shape. And the overall look of the boat should stir your soul so that you like being seen in it. That may end up being a cruiser that's angular and capable of higher speeds, but for me, it would look more traditional and get better mileage.

Different horses for different courses...

Chuck

[reed1v]

Originally Posted by fargo007

Hi,

The wife and I are looking at different types of boats, and we sort of find some overlap between what people call a trawler and a "cruiser."

I understand the displacement hull vs. planing, but when both are diesel the fuel burn seems to shake out reasonable close.

We want a solid boat with diesel motor(s) that sleeps us and a guest couple that we can make single runs between fuel ups of around 150nm absolute max (and that's padded a LOT). Mostly coastal, keys, and bahamas stuff. Overall cost of the vessel matters more than fuel economy or speed of travel.

I can find lots that we can afford in both of these worlds, but what am I missing here in the decision process?

Or am I just hung up on the cruiser/trawler monikers?

Thanks, and happy to have joined. A lot of good info here.

When we retired from sailing we bought a Grand Banks trawler. Did not like it much after a while due to the noise, the smell, the rolling, the constant need to refill the tanks, and the lack of the sailing mystique that grabs the soul.