How many knots (lost)?

[MapisM]

Yup, agreed. And the effect is also exponential, sort of.
At 60+ mph, drag (and weight, too) matters a LOT! :encouragement:

 

[PowerYachtBlog]

Now, that made me laugh.
And as often when something makes you laugh, it's not because it's funny, but because it's true!

But you know what, I really don't like fast CRUISING.
Yes, I did make some miles at P speed lately, but that's only because the DP really comes into his own north of 20kts.
She's steadily on the plane at 15 or so with full flaps, but you just feel that she prefers to go a bit faster.
That said, I maintain that I would have preferred a Nordhavn or similar, if only they weren't selling for silly prices...
Not that I'm complaining, mind. There are worse things in life than owning a nice P boat!

Back to the point, what I actually like is fast DRIVING instead, but that's something different.
With a boat, the driving pleasure has to see with how fast the boat can go only up to a point, because size is even more important: the smaller the better, obviously.
50+ knots on a big Otam or whatever will never be anywhere near in terms of driving fun to a 20 footer with a 2 stroke Mercury 2.5 EFI screaming behind your ears.
So, what's the point of using a large boat for actually CRUISING rather than driving at 50kts...? :ambivalence:
Naah, you can as well cruise at a civilised speed and take your time, imho.

If u ask me I think that full displacement boats in the med are very boring, since in most cases the Europe part of the med on average every 20 nm you get a marina.
For me I would say comfortable cruising is around 25 knots.
A Nordhavn or similar starts to make sense in my book once you want to explore areas, which are beyond the usual yachting grounds.
Think Africa, South America, Pacific Ocean and the islands that come in between.

As for your last when I was young (for 4 seasons in late 80s) I was grown up on boating in a Sunseeker 20 Mustang which reached a speed of 50-53 knots (60 mph).
It was fun but the sea state force 3 or more affected a lot the ability for it to have fun at those speeds. Which is pretty common sea condition around here.
With a Magnum or an Otam you can actually cruise always at mid 30s - 40s without bothering about Summer moderate sea states Beaufort force 4 want bother it much if any at all.
So that is the selling point of the big fast open I would say.
Another SP is for reaching 100 nm Sardinia or Corsica in three hours from one of the central to north Tirrenian sea marinas.

 

[Portofino]

P it's a bit early to be " hangering up " seas still swimable and the sun still shines 25 degree here off Cannes yesterday .
We normally pack in mid / end Oct until early May -boat sits in the water .

Where is it the boat btw -sorry I've lost track of your del trip from Venice .

You are gonna as PYB infers - have to get used to planning properly @ 25 knots .

Also maintaining excellent stern dear hygiene thoughout the season , one way or another you engines will love you for doing that .:encouragement:

What is the sweat spot rpm wise for your MAN ,s
Mines a healthy 1780 rpm which equates to 27 knots and 180 L / h ---- and important 80 % load

Just out of interest what's everybody else cruising at rpm wise with MAN , MTU , CAT and VP D12/13 ??

 

[PowerYachtBlog]

Just out of interest what's everybody else cruising at rpm wise with MAN , MTU , CAT and VP D12/13 ??

Last year I skippered a Cayman 58 WA HT from 2005 with Man R6 800hp, and its sweet spot was 1930 rpm and 26 knots cruise (25 knots at full to 8/10 fuel) and six adult persons on-board plus luggage etc.
Fuel capacity is over 2000 liters.
Fuel consumption at 95 lph per engine 190 lph total.

I painted the props/rudders/shafts with prop-speed which i have found really good after doing it over a couple of boats for clients.

 

[MapisM]

You are gonna as PYB infers - have to get used to planning properly @ 25 knots

Yeah, I guess I'll have to.
At anything between 1800rpm/23kts and 2000/27, she goes like a freight train, and also the comfort ain't too bad.
In a completely different league vs. a stabilized D boat of course, but definitely more than good enough.
With the side advantage that in this speed range I'm not missing the stabs at all, and we already decided that a gyro would neither be worth the cost, nor the weight and space.
When pootling, it's a different story of course, but the typical short waves of the Adriatic are probably the worse situation that a non-stabilized P hull can encounter.
In my usual boating scenario, when going out in glorious sunshine and just a bit of breeze waves, I'm expecting that neither pootling nor anchoring will be a problem.
In fact, for us anchoring never was a big deal also with the old lady, whose Naiads were not STAR enabled - and her round bottom was definitely more prone to rolling than the DP. We'll see...
The much busier Sof waters are yet another story of course, and I can see why nick, Deleted User, jfm etc. are happy to have STAR stabs - regardless of whether fins or gyro.

Sorry, I can't tell you anything about the engine load or other parameters - old school mechanical stuff, remember...
But based on the "seat of my pants" feeling and analogue instruments indication, the engines are running very sweetly at anything between 1600 and 2000.

Ref. my delivery trip, it was postponed to early next summer, for several reasons - the final straw being swmbo's broken foot.
That's the reason why the DP went inside a shelter yesterday.
And if you think that this time of the year is still good for boating, you must have never been in the N Adriatic.
Me, I'll rather fly to CF in a couple of days, staying onboard the old lady (as a guest! ) and swimming till I'll drop, at least for the whole month of Oct... :encouragement: