Technology?

If money isn't a consideration, absolutely. They have a variable speed motor and the water pressure stays constant so the temperature in the shower isn't constantly changing like with a shallow well pump.

Volvo has come up with a new stern drive with counterrotating pulling props. Starting for gasoline engines with stronger versions for diesel engines to follow.



What do think about them?

Sounds like Volvo is building their brand once again with patented technology. The duo-prop was terrible until the patents expired. IPS was terrible until Zeus got around their patent by turning the props rear facing, and the forward facing props were then all sorts of bad. The bottom line is that Volvo technology has always been very good, in fact a leader. So I'll trust them on this. It's certainly less turbulence hitting the props. That means more efficiency and less cavitation, and boats with this will be a lot safer for swimmers. It'll also be a good step in moving buyers from I/O's to IPS. Is it a big technological advance? I don't know, but I think it's a good marketing move.
Now of course the competition will start with the 'forward facing props are more likely to get dinged' (which the evidence I've seen doesn't support). What it will do is keep the discussion being about Volvo, and that's good for sales.

From what I have heard so far, this is not yet set to be used to replace all I/O's but it is aiming to take some companies such as Glastron, Larson, Rinker, which are generally bow riders into the tow boat area and compete with Nautique, Tige, Mastercraft, etc. From what I have seen it looks promising in the videos. The current issue with this set up is, if someone wants to get any real performance from it, it will be difficult because it has to be set so deep below the bottom. I currently have a volvo set up in my boat and love it, so I am excited to see how these turn out once a few more are out there.

This is exactly what I thought. The props are almost under or at least partially under the rear of the hull. They need some prop clearance. Which means, for higher power / torque versions, Volvo needs drives with greater offset for the bigger wheels, which means, different drives for different engines and not just different props like on the DP sterndrives.

We have a 43 ft Flybridge planning boat with dual D6-400 DP sterndrives in the family (swedish production boat). The sterndrives propel and maneuver the 26.000 lbs boat quite well and docking with the joystick system is a no brainer (also it works not as perfect as on an IPS boat). I believe, 2 x 400 HP sterndrives with pulling props would increase the performance of this specific boat quite noticable, because the propellers are biting into undisturbed water. Btw, it is amazing, how fast the 1200 liters of diesel fuel disappear at WOT . An old chinese saying: "A long alm on the thlottle will cost a lot of money" .

The new drives will not replace the standard DP drives, it will be an addition to their portfolio unless the market completely switches over to the new drives. Lets wait and see, whether and how much Volvo is willing to invest in this new technology.

I personally was waiting for the IPS 1500 or 1800 with the D16 engine. Has anybody heard any news or updates about this new drives.

It looks like these drives are mainly designed for the yacht express market under 42'. Boats like mentioned above such as regals, searays, etc. Problem is, stern drives are horrible when it comes to reliability on these boats that sit in saltwater all of the time. Straight inboards are definately much much better in long term reliability and ease of maintanence. These drives are also not going to do anything or be useful for the faster boats due to the drive height.

So is it worthwhile for such a slim market segment.

You are correct, Sterndrives need much more care in salt water than just a simple SS shaft and prop. Otherwise they will rot away under your but.

But sterndrives are perfect for magayacht tenders because of the lower storage height of the boat. They are out of the water most of the time anyway and they are cleaned after use and last, mostly very well maintained.

My son in law uses his boat mainly on the Weser River, which is a tidal river but he has it located upbound the first lock, means the boat lives actually most of the time in freshwater. The boat starts its 3rd season next week and never had any problems with the engines or drives. His biggest problems are the speed controls on the inland waterway part of the Weser River .

Personally, I do not like outboard petrol engines. I raser have a diesel sterndrive (or even a waterjet inboard diesel) tender in underdeck storage on my boat, than any kind of petrol inboard or outboard, just for my the peace of mind.

Bombs belong under a wing station or in a bomb bay, where you can jettison them in case of emergency and not in a confined space on a boat with my family on it, period!

Just my 2 (Euro) cents

Some industries are prone to radical improvements over the years due to the freshness of the industry. It's also a matter of how much information there is for the development of a product, but that in itself is dependent on scientific understanding and breakthroughs, which themselves will dictate how much innovation there is a product field.

For cell phones the miniaturization (molecularization) of transistors and capacitors wasn't just for cell phones, but for all electronic applications. Yet the upshot is that few people rely on old fashioned Walkmans and large bulky phones.

Where I live, computer hardware and research into better CPUs, RAM, or electronic computational technology that performs instructions different than current technology (so called quantum technology) is the hype. Will it happen? I have no idea. But if it does, then that means a whole new branch of computer engineering.

Yachts, by virtue of their size and where the operate, get tweaks to electronics like everyone else, like with all engineering applications there are only so many ways to shape a physical component to effectively and more efficiently interact with the world; land, sea, air, space and so forth. That doesn't mean that there won't be innovations coming about, but the need and desire to modify hull design is a bit different from, oh, say something like tactical aircraft engineering or civilian aircraft. For any application there needs to be an advantage to incorporate an improvement. Whether it's more stealthy or maneuverable tactical aircraft, or civilian aircraft that can carry more people either by using proportionally less fuel or faster to make it worth while.

When I was growing up yachts came in two flavors; sail (yawl, ketch, schooner, so forth) and motor yachts that were roughly the same length as the big sailing yachts, but broader, more accommodating, and of course were motorized and had all kinds of amenities.

But today, cruising this website, and checking out the market for both charter and yachts for sale, I'm really blown away by how big and opulent these things have gotten. Here in the San Francisco Bay Area most of what you see are sailing vessels in the 40 foot range. Something like Attessa from "Overboard" with Goldie Hawn and Kurt Russel is very rare here. Yet when I signed onto this forum and cruised other yachting sites, it's like a whole new world.

That's leaps and bounds from when I used to sail off shore way back in the 80s.

My point is that there's been tons of innovation, but sometimes we don't see it because we're so used to the latest technology. Years back there was talk of EM (electromagnetic) drives, where a cat hull acts as a giant Gaussian conductor that grabs the electrons of H2O seawater, sucks it in between the two hulls, and kicks it aft. Think of it as a giant electronic water jet. Yet the electrical engineering technology (note; NOT electronic engineering) isn't quite there to give the same kind of power of a pump jet or propeller.

Imagine your yacht having a miniature nuclear reactor. It may happen in the next twenty years. Japan (I forget the firm) was in the market of developing home nuclear reactors to cut down on power demands. That was thirty years ago. I've not heard anything since. But, China is reviving an old American concept of the Thorium reactor. The advantage being that thorium reactors don't give out all the waste that current uranium reactors do; i.e. you can't make weapons' grade plutonium from these things, meaning they'll be safe in the hands of some nut case who has idiotic dreams of destruction. Ah, but no one, until recently, has looked into reviving thorium reactor technology.

Again, innovations come, but it's reliant on what kind of understanding of science we have, and what advantage there is in an engineering application.

Phew. I hope that helps.

Blue Ghost, former aerospace engineer and film dude.

A quick followup on the thorium reactor concept by Hank Green of SciShow;



I'll try and find a link to the magnetic drive (it was showcased in Popular Science way back in the 80s).

Hi:
Hope you are doing great.
Do you experience any kind of problem with the mach 5 pumps.
I have this pumps on board and after a period of time the fresh water is not used on board the pumps with out reason stop working. I have to switch off and on the breakers in order to put the pumps back to service. Any idea why is this happening?
Thank you.