Rodman 41with IPS.

I had an outdrive boat for 10 years with no major problems - sorry to disappoint you again. Keep peddling the horror stories though if that makes you feel important, I’ll just carry on enjoying my boats and not worry if you that’s ok with you?
 
Short memory, Switch?
Beware, that's an excuse typical of us old farts.
I already said this some posts ago: if you're happy, we're all happy.
And as the saying goes, God helps happy people! (y)
 
Gor blimey Guv.


For boats of any age , likely to be owner maintained and doing more than the usual 50 hours per annum, shafts is the way to go, simply because of the KISS principle.
Have recently looked at a 30 year old boat with 600 hours on the tachos.
For newer boats where much time is spent trying to get in and out of a labyrinthine marina, with the feeling that owners of every single nearbye boat are onboard watching your every move, anything that instills a bit more confidence in a skipper cannot be bad thing.
Many times get the impression that the mere thought of getting back on a berth, ruins entire trips for some boat owners.


Thoughts and observations.
Newer boat much much shinier and airer inside with more space, howver just vaguely disappointing that a modern boat hull with a bang up to date drive system felt less comfortable underway than a hull designed in early 1980s using a drive system first installed in 1839.
Progress eh :)
 
oldgit said:
houghts and observations.
Newer boat much much shinier and airer inside with more space, howver just vaguely disappointing that a modern boat hull with a bang up to date drive system felt less comfortable underway than a hull designed in early 1980s using a drive system first installed in 1839.
Progress eh :)
Click to expand...

I think there is a lot of truth in what you say. New boats do seem to be marketed as floating apartments with lots of space and storage with large windows, nothing wrong with that I guess if that's what the customer wants. , I do think as a result (and as you say) looks and sea keeping may be slightly compromised as a result.
 
oldgit said:
Thoughts and observations.
Newer boat much much shinier and airer inside with more space, howver just vaguely disappointing that a modern boat hull with a bang up to date drive system felt less comfortable underway than a hull designed in early 1980s using a drive system first installed in 1839.
Progress eh :)
Click to expand...

That's certainly not an IPS specific thing though is it? Plenty of shaft drive boats out there with far higher sides, higher Cog, flatter hull sections, all in order to increase internal volume.

Why? Because people want/buy internal volume.

Result is the same, worse seakeeping, but you're a brave (or a niche) builder if you build a boat for some bloke on a web forum who's never going to buy it rather than for your actual customers. :)
 
ari said:
That's certainly not an IPS specific thing though is it? Plenty of shaft drive boats out there with far higher sides, higher Cog, flatter hull sections, all in order to increase internal volume.

Why? Because people want/buy internal volume.

Result is the same, worse seakeeping, but you're a brave (or a niche) builder if you build a boat for some bloke on a web forum who's never going to buy it rather than for your actual customers. :)
Click to expand...

Doubt the Phantom 46 has any more windage or the Turbo 36 but both have the engines in the middle of the boat not towards the aft end.
All aspects of motor vehicles have improved beyond recognition since the 198Os, especially ride comfort and handling, interior improvements came as part of the package.
Not so in the boat world .
 
ari said:
That's certainly not an IPS specific thing though is it?
Click to expand...
To some extent it is, because even if the main IPS raison d'être are the ones I mentioned in post #16, it's undeniable that it also has the side advantage of requiring a bit less e/r space, AOTBE. And less e/r space means more space elsewhere, which is obviously another selling point, particularly with newcomers which surely don't buy boats based on e/r accessibility.

But actually, interior spaces and windows aside, whose obsessive search obviously affect any boat regardless of their propulsion, the choice of IPS affects seakeeping and comfort more than any other systems regardless.
In fact, as I already mentioned, pods require a rather peculiar hull shape, which no naval architect would even remotely consider for a planing hull, if it weren't for the need to mitigate undesired side effects of pods.
And since one pic is worth a thousand words, here's one example of a hull specifically designed from scratch with IPS propulsion in mind, and strictly optimized for it.
If this isn't enough to remind of Heath Robinson, I don't know what else is... :rolleyes:
TbRxnDJy_o.jpg
 
So on a more serious note , here’s a mate of mine in his Porto 47 .This was designed for twin shafts , but around 2008 ish with IPS all the “sales “rage S/Sker did what MapishM is saying they took a nice fairly balanced hull cog and installed IPS .
I think at the time MBM did a back to back review of a shafts + IPS , the fuel burn was better at low planing , but equalled the shafty at high .
His sold it btw , one season after buying .
Cruising in Co was a pain as he would come over on the VHF as ask me drop the rpm s .
24 knots and he got alarms + the ride suffered because it was soooo far bow high due to the changed cog .Even with full flaps , here we are at 22 knots ( his request ) .
The AoA is far too high he has to pop his head out over the screen .
Too much weight at the back .
317516A3-8377-4387-8607-1198821EEF7C.jpeg
Remember this boat has a 1/2 decent dead rise ,so not as much NEEDED stern lift as the pic MapishM posted .
 
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S/Sker then came up with a dedicated IPS only hull the San Remo 48 .
I have a mate with one of those , but thought kindly on Switch ^^^ .Thinking 3 is a nice example .
Lets not go there
 
Portofino said:
So on a more serious note , here’s a mate of mine in his Porto 47 .This was designed for twin shafts , but around 2008 ish with IPS all the “sales “rage S/Sker did what MapishM is saying they took a nice fairly balanced hull cog and installed IPS .
I think at the time MBM did a back to back review of a shafts + IPS , the fuel burn was better at low planing , but equalled the shafty at high .
His sold it btw , one season after buying .
Cruising in Co was a pain as he would come over on the VHF as ask me drop the rpm s .
24 knots and he got alarms + the ride suffered because it was soooo far bow high due to the changed cog .Even with full flaps , here we are at 22 knots ( his request ) .
The AoA is far too high he has to pop his head out over the screen .
Too much weight at the back .
View attachment 98585
Remember this boat has a 1/2 decent dead rise ,so not as much NEEDED stern lift as the pic MapishM posted .
Click to expand...

I've seen an Itama 50 ride something a bit like that
 
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