[AMG]

As Diesel Electric propulsion with azipods is getting more popular with larger yachts, Volvo Penta is launching their new drive for inboard diesels.

Together with the new engines in the D6 series, fantastic machines I have to say since we use them on Aquamatic already, VP are now making history with a pod-like propulsion for powerboats 35-50 feet. (To start with).

It consists of a steerable house with two propellers facing forward to work in undisturbed water. Steering is 26 degrees for manouvering reduced to 13 in speed since it is very efficient compared to normal rudders. The steering is computer controlled as in recent luxury cars.

Coupled to the 310 hp D6 they call it IPS 400 since they claim it is getting the same effect as 400 hp on a conventional shaft. With 375 hp D6 the name is IPS 500 of the same reason.

Exhausts are through the drive under the bottom, reducing noise by 7 dB. Speed gain and fuel efficiency is something like 20-40 percent over shafts!

Compared to shafts in tunnels they will increase the draft marginally and if worst happens, you hit a rock in full speed, the whole unit will fall off without causing damage or leakage and a new drive can be fitted.

Good news for all of us still playing with "smaller" boats! World premiere will be at the London Boat Show in January 2005 as I understand it.

/Lars

[YachtForums]

Way to go Volvo Penta!! Add another "first" to their line of products, in addition to the Duo-Prop system, the first inboard/outboard drive and others! I would be surprised if production will be able to keep up with the demand.

Thank you for bringing us this information Lars!!

[AMG]

As an additional information, at least initially, the new Volvo Penta IPS will only be delivered as a twin package. Included is the electronic shift/throttle and the electronic steering, making this a dream pack for the shipyards. One hole in the bottom for the steerable drive including water intake and exhausts. Only a set of wires to connect to the bridge/flybridge!

As an illustration I have put the package with IPS 500 into my 40 feet design which I believe would be an ideal combination for a cruising speed near 40 knots.

[YachtForums]

I have to give you credit Lars... few people can adapt and implement new systems within moments of learning about a new technology. If it only it were this easy during the actual construction! Ultimately, these new pod systems will be much easier to integrate into new and existing hull designs, rather than conventional prop, shaft and rudder configurations.

While podded drives offer many time, space and cost saving benefits, they may not be the drive of choice for higher speed hull designs, unless they are mounted to an extension off the transom that raises their X-Dimension, or... recessed behind a notch/step in the hull. Even with this location, the current systems do not offer trim features. Hopefully engineers will be able to address this in future product offerings.

[AMG]

You are right Carl, as I understand it these new drives are to replace shafts and rudders on existing such designs and typical small/medium size flybridge boats. For higher speeds on lighter crafts you have the new Aquamatic and for boat speeds between 47 and 60 knots there is the R-drive which is two inches shorter, or lifted.

[Yachtguymke]

Tiara was the first to integrate this system into their boats. They used the Tiara 38 Open as a testbed for the new system. It will be at the Miami show. Tis system will work really well in the Tiara Sovran Series by giving it the Mid or Aft Cabin in lieu of the enigines being so far forward in the boat. I am anxious to see this. Our current customers are gong to love this new features - Especially the wives. They get more room.

[AMG]

Yes, you are right, a handful of producers has been participating in the testing and at the Press meeting on Mallorca they had two Cranchi 41:s. One was fitted with shafts and rudders and the other with IPS, both had the same D6 engines.
The top speed was 31 versus 37 knots and fuel consumption at 30 knots, 135 versus 95 lt/hour. I guess that both the boat builders and buyers will stand in line to get them...

[sarnacho]

Astondoa shipyard installed in one AS43' the IPS system, and as far as I know they were surprised, as manouvring and speed were increased with the IPS from Volvo.

Normally this small flybridge boat is built with 2 x 430 hp Volvo Penta, with regular direct shafts, props and rudders.

This pod IPS system can bring new solution for power boats.

Great! Congratulations Volvo!

Sarnacho.

[brian eiland]

About three years ago I had mentioned my interest in such a configuration to the Volvo rep at the Ft Lauderdale show. He said I should come visit them in Norfork. I never did take the time to follow up on that invitation. I suspect they have been working on this for some considerable time.

I had previously suggested this idea for both single and/or dual props, but utilizing a kevlar belt drive component rather than 90 degree shafts:
From my website,"Other than direct straight-shaft drive of propellers, most marine drives today involve some sort of 90 degree arrangement, ie.sail drives, stern outdrives, outboards, etc. The 90 degree gear set (and there are usually two sets) is the potential weak link in the system. All the power is being transferred over a very physical small contact area between two bevel gears. This contact patch can be nothing more than a thin line on the opposing two teeth! Special hardened gears and maintaining close-fit tolerances permit the horsepowers of today. But when it comes to diesel engines, the situation gets worst. The diesel is by its nature a much more torque'y beast. Gears to handle an even modest horsepower diesel are extra hard pressed. Teeth can break or get worn so quickly as to loose all tolerance."

Volvo is talking some fairly big diesel power here. I can only think that the smaller dia props (dual configuration) are a factor in making it work, but I still have trouble believing it. I wish them the best of luck in a successful product.


PYI is now using a Morris chain drive component in lieu of the kevlar belts:
http://www.pyiinc.com/?section=drive_leg&sn=1

I still believe the kevlar belt idea merits research, particularly in this forward facing config., and as simplier, less expensive possibility. Couple of older references on the belt subject:

http://www.boatdesign.net/forums/sh...681&postcount=4

http://www.boatdesign.net/forums/sh...12&postcount=11

[AMG]

Hi Brian,

Over a period of six years a growing group of technicians has been working on the IPS project (Inboard Performance System). The beauty of it is that opposed to their saildrive, this is steerable. I can imagine your idea of a belt drive is good for other manufacturers in making non steerable drives, but I can not see it used in this application? Maybe you can bend it a couple of degrees at most?

If there are week points in this drive remains to be seen, but what I heard is that the drive already is prepared to host bigger mechanical parts to handle more horsepowers in the future. We´ll see.

[YachtForums]

Brian,

Did you ever finish the model of that "forward thinking" cat? If so, please post a picture of it in forums!

Best...

[CaptPKilbride]

I like the looks of this

[AMG]

Originally Posted by CaptPKilbride

I like the looks of this

Yes, and I like the looks of the Schottel Twin Props, but only for bigger yachts since the weight for the drives alone are between 1 and 8 tonnes...

[brian eiland]

Originally Posted by brian eiland

....PYI is now using a Morris chain drive component in lieu of the kevlar belts:
http://www.pyiinc.com/?section=drive_leg&sn=1

Thought I would bring up this reference subject again with a photo, and then solicit anyone to define the "Morris chain" component in this drive leg??

I know such a 'chain' was utilized on the older Olds Toronado automobile.