Some observations

On my recent trip to Ft. Pierce I learned a few things. When the wife and I were looking for our next boat, there were some items I was particular to. The main was a couple of small naturally aspirated diesels. I felt that 8-10 kts was sufficent cruise speed for the type of cruising I wanted to do. I also knew I would probably not be buying a full-displacement trawer but a semi-displacement. Well over a 460 mile round trip, here is what I found. When the scenery is nice 8-10 kts is very nice but when in more open water with a 20-30 kt headwind 10 kts sucks in a semi-displacement hull.
The Amar la Vida has twin 6-71Ti Detroit diesels. After working the numbers. At 1100rpms, depending on tide I run at 8.5-10kts. The best part of that is I am burning 7 gallons per hour total with a 20-25% load on a 15kw genny. Now at 1800rpms the engines are in a nice even stride, depending on tide she's running 14.5-16.0kts burning 18 gallons an hour with the same genny load. I do not think that is bad for a 50k pound aft cabin motoryacht. I am very happy with these numbers and I believe it gives me alot more flexibility in my cruise planning without breaking the bank.

Chris, it was good meeting you and your dad in Ft. Pierce. You have a very comfortable cruising boat. Copious amount of space.

I would question running the generator at 25% load for extended periods. 15kw is a large generator. Moonstruck has a 12kw to run everything on board without load shedding. In order to keep the ginny loaded to 75% I run the heat/air units when it is on.

Not being retired (looking more like I probably never will), speed between destinations is important to me. It gives more time to hang out and enjoy being there. I still like the trawler style, but no time for the slow speeds. My son, David, and I went down to the Stuart Boat Show. For a large boat I think the Fleming 55 is the best combination of speed and accomodation.

Jacksonville with it St. Johns River, the Atlantic, and the ICW is a great cruising base. I'm sure you will get much enjoyment there.

Don it was a pleasure meeting you also. Thanks for the kind words, yes she is very comfortable and very liveaboardable which I hope to be doing in the next few years. I agree about only running the genny at 25% load. I do run at least one A/C heat,a few lights and the refrigerator. I may be running at a higher capacity I have not worked the numbers exact. I am going to add an inverter to run the refrigerator and few outlets to not have to run the generator all the time.

There are reasons why "semi displacement" hull/engine combinations are so popular.

We run our boat with Cummins 330's at 8 knots while in protected waters. The admrial doesn't like being bounced around in unprotected waters so I can run at 15 knots during those times which not only gets us there faster, it also causes the stern to squat a bit smoothing out the ride in a beam sea.

If you add a large inverter/charger you'll not only reduce your generator run time, you'll also add load to it when you are running the generator. A 150 amp charger will draw 15 amps or more when in "bulk charge" mode.

Moonstruck said:

Speed between destinations is important to me. It gives more time to hang out and enjoy being there. ....... For a large boat I think the Fleming 55 is the best combination of speed and accommodation.
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If I were doing long distance cruising, that's exactly what I would have and for the same reasons.