IPS IPS....Where Art Thou IPS ?

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oldgit

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Good old shafts in abundance.......
More outdrives than you can shake a stick at.
Even a few jet drives.
But you will search long and hard on those little propulsion option boards hidden away on base of display stands for the game changing "sweeping all before" it option of .........IPS. !
 
that's odd because my impression was the opposite - shafts (regret-ably) going out of fashion. Perhaps its the manufacturers I looked at most rather than overall.
Jeaneau, Sealine, Bavaria, Sunseeker all had IPS boats, Fairline, Princess didn't. (I wait to be corrected)
 
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IPS you see in the Channel Islands very occasionally, very few liesure boats withjet drives are seen, lots of sterndrives and lots of shaft drives.

Outdrives not so many years ago for diesel mainstream boats was limited to 230 hp now the Volvo Penta D6 is rated at 400 hp on an outdrive so a pair of these will easily drive a 45ft sports cruiser and quite efficiently too.
 
My view is that outdrives are being found on larger boats these days, and occasionally IPS, both free up space below for bigger cabins, for showroom appeal. No doubt for me that outdrives deliver fuel efficiency. Not yet convinced about IPS. The only advantage as I see it is the vectoring for mooring. However, you can now get joystick and vectoring for outdrives, so that advantage is diminished.
 
rafiki_ said:
My view is that outdrives are being found on larger boats these days, and occasionally IPS, both free up space below for bigger cabins, for showroom appeal. No doubt for me that outdrives deliver fuel efficiency. Not yet convinced about IPS. The only advantage as I see it is the vectoring for mooring. However, you can now get joystick and vectoring for outdrives, so that advantage is diminished.
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The joystick on a princess v45 doesn't work very well, the boat has too much windage and requires a bow thruster to aid satisfactory mooring.
 
Main advantage of IPS is low speed handling, because the props are even more "underneath" the boat than with shafts, and so are in the best place to turn it. In theory, IPS should be simpler to maintain than outdrives, but for some reason that doesn't seem to translate into reduced service costs, from what I hear. Reduced fuel consumption is a marginal benefit, imho.

A joystick on a long pointy boat with outdrives > 40ft isn't going to be very effective with the propellors hanging beyond the transom.

Sealine SC42 - IPS is an option.
Sealine F42 or C48 - IPS is your only option!
 
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I met with ZF planning guys back in September. Initially we discussed the impact of dissolution of Cummins Mercuiser Diesel and walked away enlightened.

IPS and Zeus take up has stalled, higher service costs than shaft drives and bow/stern thruster integration packages about to be launched, Mercruiser pulling the rug under Cummins on Zeus exclusivity leading to Cat and Yanmar offering system therefore no takers. Crummy Volvo DPH saga goes on, ZF not sitting on their hands, they can sense blood.

Over the next three years ZF set to offer outdrives up to 450 hp and totally new range of pod drives which will change the market place.

Just file this posting and wait........
 
volvopaul said:
The joystick on a princess v45 doesn't work very well, the boat has too much windage and requires a bow thruster to aid satisfactory mooring.
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I totally agree Paul, and I would probably tick the bowthruster box with IPS too. However, from a showroom perspective, the £20k odd saving for outdrives over pods is very tempting, as is the additional cabin/storage space. For me, anything approaching 40 ft will probably need shafts, but I recognise the trendy 40 ft plus hard tops all have drives.
 
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Does anyone know what happened to yellowfin? It looked such a promising alternative, seems a shame for them to just disappear.
 
FlowerPower said:
That's not a a good comparison.
The smaller boat is "underpowered" compared to the larger one.
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Hmm, look at the figures at 14 knots, the much larger shaft boat consumes 20% less and at about 7 knots it goes 3 times further per gallon. Yes there are probably many factors contributing to this but IPS is not for slow and medium speeds. You wonder why they put IPS in the ST50...
 
Boats must to have the hulls designed and optimised for shaft or outdrive or waterjets, you cant have the same efficient hull that can be powered by two or three of these efficiently.
 
14 kts = 3000rpm in the smaller boat
2250rpm in the larger one

Even allowing for the 500rpm difference in top end rpm, those mid range semi-planing speeds are not where the smaller hull is at it's most efficient.

The only valid comparison is IPS / Shafts on the same boat.
 
When you look at service costs and past reliability problems I cannot understand why anyone would buy an ips boat., the only reason I'd say is because they want that particular model which is an ips only system.
 
volvopaul said:
When you look at service costs and past reliability problems I cannot understand why anyone would buy an ips boat., the only reason I'd say is because they want that particular model which is an ips only system.
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Paul, I totally agree. It is all about freeing up space below decks for bigger cabins. Even more space is freed-up with sterndrives, which is why you are seeing these on evere larger boats.
 
V Drives - its the future
seriously how much improvement in economy/performance would a shaft drive boat have if the shaft was enclosed?
 
volvopaul said:
The joystick on a princess v45 doesn't work very well, the boat has too much windage and requires a bow thruster to aid satisfactory mooring.
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That was exactly my experience with my boss's V45, the drives are too close to provide the leverage on this size of boat. The only joystick boat that really worked well was a Windy 35 which could I could circle around a mooring buoy bows in with the jotstick alone.
 
kashurst said:
V Drives - its the future
seriously how much improvement in economy/performance would a shaft drive boat have if the shaft was enclosed?
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8%, according to Seatorque.
http://seatorque.com/boss.asp

"Reduced turbulence through the propeller due to the non rotating shaft casing, plus eliminating cutlass bearings and stuffing boxes allows for an average* of 8% extra delivered Horse Power to the propeller.

Calculate the cost of upgrading to the next size engine in Horse Power terms, and the BOSSTM makes sound economical sense."
 
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