Game Changing 42 ft Flybridge Concept? Opinions appreciated!

[Hugin]

I give you the silverton 43

:encouragement: Good find; I think I already saw it..... there are quite many unconventional designs originating from the US or Australia. It does have some kind of side decks though; they just lead somewhere else than usual

 

[Bojangles]

Hugin, an interesting thread, thanks. I like a lot of the ideas, the bow area, single engine (genny, get home solution even better) and enclosable aft cockpit.

I have a 2005 Sealine F43 which shares almost exactly the dimensions of your concept boat. I've had this boat for 6 years and love it, I can honestly say there are very few boats of the same size which would suit our use better. A couple of times a year we have 8 people sleeping overnight and it is not a problem with the 2 temporary double berths that takes only a few minutes to convert. I can say with some certainty that I would never use a kit that would be removed from the boat, just sounds like to much to think about. Most occasions when we have had 8 staying overnight it has been on an adhoc basis, so no time to install the kit.

One of the biggest factors putting buyers off buying any new boat at 350K + has to be the eyewatering depreciation, for that reason I view most new model boats that come to the market on the basis of "I wonder how much that will be at 4/5 years old"

like others I look forward to seeing more detailed drawings and CAD images of your project but good luck in the meantime.

 

[Whitelighter]

I don't like having 8 people sleeping in my 4 bedroom house. I certainly wouldn't entertain it on a sub 100ft boat.

We bought Seralia specifically because we can, if needed, sleep 8. We won't do it often but what's the point of a med toy if you can't accommodate mates for the odd weekend.

For us it means using the crew cabin and the saloon but I'd rather have the option than not be able to go to the Balearics for the weekend because we need a hotel when we get there

 

[Hugin]

but I've yet to experience any planing boat where the bow is useable at planing speeds.

Lots and lots and lots of US bowriders. Check out this one http://www.mby.com/reviews/sportscruisers/chris-craft-launch-36-review

 

[Hugin]

So far I've only seen mention of a day heads and an ensuite cabin. Is that it, 2 toilets and one shower? Or have I missed something?

There will be space for two complete "bathrooms" with both toilet, shower and a wash basin. I doubt the smaller of them will fit a separate shower cubicle though.

However I do like the idea of a single engine, makes a lot of sense. Are you planning on having a genny, any boat with a large crew is likely to be power hungry.

To Genny or not to Genny.... that's the question. :ambivalence: Today there are more options than ever before. An extra oversize alternator for quick recharging of some Lithium batteries (yes, they are still expensive but it's moving the right direction) and affordable, "intelligent" inverters. It's getting awfully tempting to do without a genny. There are of course things that will most certainly trigger a genny.

- Frequent and intensive use of hotplates, oven or maybe a washer/drier in the lazarette could tip the balance towards a genny, but it could also be countered by adding battery capacity.
- A Seakeeper 5 could in principle be run without a genny provided you had ~15 kWh of battery capacity. You could start up the main engine for maybe 2-3 hours per day (depending on the size of the extra alternator) and recharge the batteries. It will be less fuel efficient than a genny of course..... OTOH, a genny is not free, requires service and add weight to the boat. The small Seakeepers are now so cheap it would border on criminal neglect to not at least prep the boat for one. Dropping it in during build will obviously be cheaper than retrofitting.
- Aircon.... the elephant in the room. I don't know the numbers but normal use of an aircon system would very likely trigger the need for a genny, but you could in principle also have a battery powered aircon.

Another consideration. If it is decided a genny is necessary then you might as well get a 15-20 kW model and connect a 20 kW electric motor to the drive train. Then you have get-me-home capability in case of main engine failure as well as near-silent 5-6 knots cruising with main engine off. A simple hybrid system....... but that's just me dreaming about the perfect propulsive set-up. Maybe in the future.

 

[Deleted User YDKXO]

The new sealine 530 looks to be at least as competitive.

£0.5m inc VAT according to this month's MBY which is incredibly competitive considering that Princess, Sunsseker and until recently, Fairline would be asking close to £1.0m for the same size of boat. IMHO Sealine are on to a winner with the 530 even if it has rather undersized engines

 

[Deleted User YDKXO]

I strongly suspect the whole project is founded on the premise "How big a boat can we build up arond the IPS600 without looking ridicules" I think they went at least 3-4 tons too far. Nothing wrong with reducing speed requirement, but then the rationale for IPS is literally blown out of the water.

Well it is a Bill Dixon design so its probably going to be more right than wrong, especially given how well received the other recent Dixon designed Sealines have been. Also AFAIK the only pictures anyone has seen yet have been computer renderings so the finished article is likely to be very different

As for the IPS engines, I'm not sure what you mean by the rationale for IPS being 'blown out of the water'. The main rationale for IPS is to push the engines further aft to release more space forward for accommodation and the cabin accommodation on the 530 seems to be suitably commodious as a result of the IPS installation. The other rationale for IPS is the joystick handling which I'm sure is fitted to the 530. I guess you're referring to the supposed high speed efficiency of IPS? Well the jury is still out on that one. Boat tests seem to suggest that any efficiency gains over shaftdrive boats are marginal to say the least, especially for IPS equipped flybridge boats. So I don't think that Sealine's decision to use IPS falls down just because the engines are a bit underpowered. In any case, according to MBY, larger IPS engines may be offered as an option

 

[Hurricane]

Hugin, an interesting thread, thanks. I like a lot of the ideas, the bow area, single engine (genny, get home solution even better) and enclosable aft cockpit.

I have a 2005 Sealine F43 which shares almost exactly the dimensions of your concept boat. I've had this boat for 6 years and love it, I can honestly say there are very few boats of the same size which would suit our use better. A couple of times a year we have 8 people sleeping overnight and it is not a problem with the 2 temporary double berths that takes only a few minutes to convert. I can say with some certainty that I would never use a kit that would be removed from the boat, just sounds like to much to think about. Most occasions when we have had 8 staying overnight it has been on an adhoc basis, so no time to install the kit.

One of the biggest factors putting buyers off buying any new boat at 350K + has to be the eyewatering depreciation, for that reason I view most new model boats that come to the market on the basis of "I wonder how much that will be at 4/5 years old"

like others I look forward to seeing more detailed drawings and CAD images of your project but good luck in the meantime.

Funny, when I read the OP (#1), I immediately thought of the F43 - got be one of the most forward thinking boats ever built.

Personally, though, new concepts come and go all the time.
Some stick - other ideas fade and are forgotten.

I believe that as the OP goes through the development, he will end up more conventionally that the initial concepts.
There is a reason why designs like a Flybridge Cruiser exist - and it is because they have evolved into what they are now.
I'm sure there are reasons why some of the OP's ideas haven't been seen to date.
Lets take the excellent ideas on the foredeck access - I suspect that you wouldn't get a design like that through the coding regs - just look at what you have to do with hatches.
Anyway, interesting concepts do sometimes come through - mid cabins and hydraulic bathing platforms for example.


EDIT - I wonder what ever happened to the internal flybridge stairs???

 

[jimmy_the_builder]

Lots and lots and lots of US bowriders. Check out this one http://www.mby.com/reviews/sportscruisers/chris-craft-launch-36-review

No, sorry - that's a very poor example. I defy you to sit comfortably on that bow seat at planing speeds. In that video, there was very little footage taken on-board while underway; see how much the camera is bouncing around at 2'35 - and that's at the helm. Extrapolate that to the bow and my point is conclusively made.

 

[jimmy_the_builder]

£0.5m inc VAT according to this month's MBY which is incredibly competitive considering that Princess, Sunsseker and until recently, Fairline would be asking close to £1.0m for the same size of boat. IMHO Sealine are on to a winner with the 530 even if it has rather undersized engines

Just by-the-by, the Chris-Craft Launch 36 (a big US bowrider) that the OP linked to above is quoted at £478k+vat, yikes...

 

[Deleted User YDKXO]

Just by-the-by, the Chris-Craft Launch 36 (a big US bowrider) that the OP linked to above is quoted at £478k+vat, yikes...

Worth every penny IMHO

 

[Hugin]

Also AFAIK the only pictures anyone has seen yet have been computer renderings so the finished article is likely to be very different

I would hope so, but I'm not so sure since several dealers already advertise a base price... I found €600K + VAT. One would think the project had progressed beyond the initial renderings if there's already a fairly accurate price available. But we'll see.

Either way, at that price I think Prestige 500 wins hands down at €532K + VAT with identical propulsion. It has a much better layout in regards to cabins as well as the salon. Plus it gets 29 knots and at 3 tons less displacement should be more economical at cruising speed.

As for the IPS engines, I'm not sure what you mean by the rationale for IPS being 'blown out of the water'. The main rationale for IPS is to push the engines further aft to release more space forward for accommodation and the cabin accommodation on the 530 seems to be suitably commodious as a result of the IPS installation.

I believe this rationale was invented later as the efficiency claim didn't hold water. IPS is not a particular compact system anyway. If you really want to free up space then get three D4-300 with stern drives instead of two IPS 600 pods. Weight will be virtually the same and price lower. Servicing costs also lower and I could even see the possibility of pootling along with only one D4-300 running, the 2 other drives raised.

IPS was initially "sold" on the premise it provided up to 35% more speed with identical horsepower. Or that significantly smaller engines could be used without speed loss. The designation "IPS600" tells the story. Volvo Penta strongly tries to imply their system has the propulsive efficiency of a traditional 600hp shaft arrangement.

The efficiency was especially claimed for higher speed applications; i.e. above 30 knots, which makes sense when you consider the forward facing CRPs. IPS is simply built for high speed, where the traditional shaft configuration loses out due to exponentially increasing drag as speed goes up. The drag component is (claimed to be) significantly lower for IPS, which means the higher the speed, the more IPS is a winner...... until we hit the territory of surface drives. Around 25 knots there is no measurable efficiency gain from IPS, so the extra money for the system is kind of wasted

The other rationale for IPS is the joystick handling which I'm sure is fitted to the 530.

That rationale is long since dead and buried. Today you can get joystick handling for any propulsion system except the single stern drive and the single outboard...... and I'm not even sure there doesn't exist a solution for these cases too.

The simplest, least wasteful joystick handling system is based on proportional power bow and stern thrusters and conventional shafts, whether single or twin. IPS have to apply some rather powerful thrust vectors to swing the boat around solely with the pods. Here a bow thruster is invaluable and do the job with much less power input.

Anyway, I wanted to add that another Bill Dixon design.... the also brand new Galeon 500 Fly has the same cabin set-up and a better salon set up.... as well as some innovative tricks like fold down-sides and (optional) a huge rotating cockpit bench with table. It's offered from €550K + VAT with two Volvo Penta D9-575 and V-drives. Just to illustrate IPS is not the only way to free up space for accommodation.

In any case, according to MBY, larger IPS engines may be offered as an option

They wrote about the Galeon 500 it would be available with Z-drives or pods...... nothing about V-drives. So trust MBY; just don't trust EVERYTHING they write

Sealine's website does not mention upgrade options and the problem is going up to IPS800 adds more than 1800kg to the boat and probably almost €100K to the price. Volvo's (and Sealine's) problem is that there is a huge jump from IPS600 to IPS800 in every possible aspect. We therefore see builders trying to squeeze IPS600 to the limit and beyond, because IPS800 is just not an attractive option.

 

[Hugin]

Worth every penny IMHO

As long as we are talking pennies :ambivalence:

 

[Hugin]

I immediately thought of the F43 - got be one of the most forward thinking boats ever built

+1 to that. I can reveal that our first layout attempt included a larger aft cabin imitating some of the "tricks" providing headroom in the aft cabin of the F43. But we couldn't get enough headroom and the cabin became too claustrophobic anyway, so we dropped the approach.

I believe that as the OP goes through the development, he will end up more conventionally that the initial concepts.

What I have presented IS the more conventional concept. You should have seen the first ideas.... some of them impossibly complicated and expensive

There is a reason why designs like a Flybridge Cruiser exist - and it is because they have evolved into what they are now.

I would have to disagree mildly with that. Many designs owe their continued existence to habitual thinking. The fact that costumers are not actively protesting (but they might simply stay away instead) a feature or a solution is taken as proof that they wouldn't accept any changes. I have studied the products of dozens of minor Italian, Spanish, UK and especially Scandinavian boat builders and I can confidently say that half of them have never fostered a design idea of their own. They simply produce exactly what they can see is already on the market..... I very much doubt they make any market research or critically assess the desirability of their products. A minority deliberately attempts to be different, but too often they don't think practicability into it. Check out Marino APB 27 for an example of that.

Lets take the excellent ideas on the fore deck access - I suspect that you wouldn't get a design like that through the coding regs - just look at what you have to do with hatches.

I'm happy you find the idea excellent. I'm not so worried there should be significant problems getting the design approved/certified. There already exists designs with forward facing openings/hatches/doors and "deck troughs" which would be far more vulnerable to a "wrong sea" hitting in the worst possible way. Check out XO 270 RS Cabin for an example. It has a forward facing door with a larger area than what I am contemplating. And the "trough" would in the worst case scenario (where it is filled completely with water) add something like 50% to the total weight of the boat. A similar worst case scenario for our design would add maximum 15% to the boat's weight and the water would start to self-drain immediately.

 

[Deleted User YDKXO]

I believe this rationale was invented later as the efficiency claim didn't hold water. IPS is not a particular compact system anyway.

No thats wrong. I remember when Volvo launched IPS, one of the selling points was that it moved the engines further aft thus freeing up space for accommodation. Whether or not IPS is 'particularly' compact or not, it takes up less space than a traditional shaft drive set up

IPS was initially "sold" on the premise it provided up to 35% more speed with identical horsepower. Or that significantly smaller engines could be used without speed loss. The designation "IPS600" tells the story. Volvo Penta strongly tries to imply their system has the propulsive efficiency of a traditional 600hp shaft arrangement.

Yes I know all that. Lets just say that the results have been mixed. IPS seems to give proportionately better efficiency gains in lighter sports boats than heavier flybridge boats for reasons nobody seems to be able to adequately explain. My point was that Sealine won't have chosen IPS for efficiency reasons at high planing speeds but for reasons of maximising accommodation

That rationale is long since dead and buried. Today you can get joystick handling for any propulsion system except the single stern drive and the single outboard...... and I'm not even sure there doesn't exist a solution for these cases too.

Yes I'm well aware that joystick control is available for other propulsion systems but the IPS joystick has been around for a lot longer and by all accounts works better than the other systems

Sealine's website does not mention upgrade options and the problem is going up to IPS800 adds more than 1800kg to the boat and probably almost €100K to the price. Volvo's (and Sealine's) problem is that there is a huge jump from IPS600 to IPS800 in every possible aspect. We therefore see builders trying to squeeze IPS600 to the limit and beyond, because IPS800 is just not an attractive option

Point taken. I suppose the proof of the pudding will be in the sales figures. If the 530 turns out to be the lemon you say it is, then your boat will outsell it by miles

 

[Nigelpickin]

Stretching it a bit to consider crew quarters a 4th cabin. The awkward access and lack of headroom disqualifies it a bit, but OK...... 3 and a half cabin maybe.



Yes, it's very interesting and I'm not quite sure what to make of it. On one hand potential buyers are (seemingly) rejecting boats of roughly the same size and weight as I'm working on. That's a negative of course.
So do the clients rejecting a Prestige 420/450 dig at least €104.000 + VAT deeper into their pension savings to get the 3rd cabin (and more space overall, of course) of a Prestige 500?
Or do they save €54.000 and get the 3rd cabin from Bavaria (or Galeon)? We simply don't know, because those on a budget and interested in 3 cabins wouldn't worthy the Prestige 420/450 a glance in the first place. And those not on a tight budget might look at other 50 ft 3-cabin boats and reach the conclusion that Prestige offered the best value overall.

What if the Prestige 450 had a 3rd cabin without diminishing the Master and VIP cabins? I'd say it would very likely hurt the sale of the Prestige 500..... but probably also the sale of Bavaria and Galeon 3-cabin boats, because the Prestige 450 is ahead of those two in regards to concept and overall space

When we made the visit to the Prestige Factory to view the unveiling of the 450, we spent around 10 minutes on that boat and then 6 hours on the 500 parked next to it, (which we ended up leaving a deposit for on the day). To be fair it was less a decision about berth spaces and more one driven by volume and practicalities, (it's usually just the two of us on board).

I dont agree re the crew cabin, (although we chose a model with the garage), its a great space and I know a couple of owners who use it for their hormonal teenager.

Re price, I think that the brochure prices are very much worst case scenario for the buyer, perhaps if they are part exchanging, thats worth remembering when you are targeting your competition.

So while I only have my own experience to draw on it was very much the case that 'just a little more' money would get us the boat we really wanted with very few compromises...A good dealer will usually find a way for a qualified customer to find the extra cash!

Agree that IPS 600 will be at the very edge in terms of their ability to get a 55' boat up and out, let alone cruise at 26 kts.

 

[squadron]

Getting back to the op , I know you said no to IPS but wouldn't it be more innovative to offer a single IPS coupled with a hydraulic bow thruster so no problem with extended use of the bow thruster and then it could be joystick control if the software exists to mate a single IPS with a thruster ? .Much easier than single shaft for low speed manouvering. This would also free up much more space below decks , seems like all the other manufacturers have embraced this to maximize internal flexibility.

Actually just found out ZF have done it , they re-programmed the software so that it could rotate 180 degree.

 

[Hugin]

Getting back to the op , I know you said no to IPS but wouldn't it be more innovative to offer a single IPS coupled with a hydraulic bow thruster so no problem with extended use of the bow thruster and then it could be joystick control if the software exists to mate a single IPS with a thruster ? .Much easier than single shaft for low speed manouvering. This would also free up much more space below decks , seems like all the other manufacturers have embraced this to maximize internal flexibility.

Sounds very expensive, complicated and a separate development project in its own right :ambivalence:

I'm afraid it's not an option in this case, even if the idea could work for other boats. The available engine room (between the two bulkheads) is only ~2m. long. The shortest version of the relevant IPS-system (IPS800 w. 625hp) is 3,3m. long and the upper part of the pod is too bulky to fit under the floor/bed of the aft cabin. Besides the bloody thing weighs 1800 kg.... yes, 1800kg just for one drive-line. The equivalent pod system with a Cummins QSC 8.3L (600hp) is not much shorter/lighter.

I don't think anyone would seriously consider a hydraulic bow thruster in a boat this size. These days you can get a variable speed 24V thruster for not that much money and with decent battery capacity you have extended run time without overheating issues (because the thruster is run at maybe 50-60% of max almost all the time). Hydraulics adds a lot of complexity to a boat where space is a severely limiting factor.

Engine choices
I need to fit the engine inside the 2m. length of the engine room, preferably in such a way that it will be possible for a person to get from one side of the engine to the other. It is not necessary to fit the V-drive within this length.... the gearbox can fit under the bed/floor of the midships cabin in much the same way the upper part of the smaller IPS pods fit under crew cabins on many boats. Assuming good noise insulation around the gearbox, of course.

The total length of a Cummins QSC 8.3L is 142cm. (the engine block is shorter of course) so that would fit the bill. The weight is also OK at around 900kg. but the total width is almost 100cm, so stealing quite a bit of the available "maneuvering space", which definitely counts against it.

The FTP N67-570 (formerly known as Iveco) is 132cm. long total, much more narrow and only 650kg. It's probably also quite a bit cheaper than Cummins, so that is becoming the favored choice.

The FPT N90-650 is significantly more powerful than the 2 other engines. At 940kg the weight is still acceptable, but it is almost 190cm long total, so it is getting a veeeery tight fit and there would need to be separate access hatches to each side of the engine room, because in no way could a person squeeze past the engine. I think it would be a great choice if only the thing wasn't so bloody big.

There is also a Caterpillar with same weight and horsepower as the FPT N90, but I don't know if it would fit.

Volvo's contenders, D9 and D11, has 575hp to 725hp, 1075-1130kg and ATEBE probably a heftier price tag than both FPT and Cummins, so I'm not sure they are even contenders - I want to keep things lightweight and affordable. The engine lengths are OK at around 145cm though.

 

[Hugin]

Agree that IPS 600 will be at the very edge in terms of their ability to get a 55' boat up and out, let alone cruise at 26 kts.

I think it will get on the plane alright - if a bit slowly - and a good cruise speed will probably be 20-22 knots..... notice, 26 knots is with a clean hull, no waves, modest load etcetera.... so probably wont happen that often. I just don't think the extra cost, maintenance liability, complexity and weight is justified when in reality you don't gain any advantages you could not have gained with a cheaper, simpler and lighter system. For significantly less money it could have 2 FPT N60-480 (or the equivalent Cummins engine) with V-drives - providing more power (+10%), more torque (+23%), less weight (~200kg) and less bits and bobs prone to malfunctions.

Incidentally the Sealine is in many ways comparable to the boat I suggest when comparing propulsive data. Assuming I go for a 570-600 hp (Either FPT or Cummins) then I make these observations:

With a 40% loading my design hits around 12 tons, while the Sealine hits just above 18 tons....... so the Sealine is almost exactly 50% heavier

870hp vs. 570-600hp is also roughlt 50% difference, so both boats will have just under 50hp per ton of displacement.

The Volvo's are weak on torque, so the Sealine will only have 20-33% more torque available to accelerate 50% more weight. My boat "wins" on this parameter.

I assume the smaller boat ATEBE* will have a 5-10% lower bottom loading; which means it potentially can get on the plane at lower speed and will need to "push aside" less water per unit of weight than the bigger boat for all planing speeds. The "form drag" component per unit of power is lower for the smaller boat.

The larger boat will have less hull area in contact with water per unit of propulsive power, so the "skin drag" component relative to power is lower for the bigger boat.

The bigger boat has four (CRPs) relatively small propellers vs. only one big propeller on my design, but the bigger boat also have 50% more horsepower (thrust) to transmit. Assuming 4x16" props on the Sealine and 1x24" prop on my design the Sealine should theoretically benefit from a 15% reduced blade loading, which isolated is a good thing. Small propellers rotating relatively fast will ATEBE suffer more slippage (propulsive waste) when trying to push heavy loads. Difficult to say, but it's probably even as far as the efficiency of propellers go.

In many ways comparable numbers and I think my design could achieve the same maximum speed, maybe even 1-2 knots higher. I've used an online calculator (with verified baseline "credentials") and it indicates 27-28 knots for 570-600 hp at a weight of 12000 kg.

*I assume LWL of ~13m. for the Sealine and 10.5 m. for my design. The LWL of the Sealine is not publicly known yet.

 

[MapisM]

I need to fit the engine inside the 2m. length of the engine room...

I guess my question might sound rude, but it's actually a genuine curiosity, and I can't think of a more polite way to ask, anyway...

Some folks who spent decades actually building boats always explained me that boat design, particularly for P boats, must start from the hull and its propulsion requirements (power/transmission/weight distribution). In turn, that defines the e/r requirements and its bulkheads. Eventually, whatever is left can be used as appropriate.

Now, what sort of new boat design methods are you using, that allow you to work exactly the other way round?
My question obviously assumes that you are still interested in getting a properly powered, balanced and overall well performing boat, without which any other advantage is useless.