What are the goods/bads of delta conic hull?

[nhmaina]

I have been looking on the web and I can't find much information on the delta conic hull. I just purchased a larson boat with one and I haven't put it in the water yet. Can't because the motor is dead. However, I noticed that larson and most others have gone away from this type of hull and I am curious why. I have never owned a boat with this hull so I don't know the goods/bads of it. Can anyone give me a quick run down of the goods/bads? Thanks.

 

[dbkerley]

Re: What are the goods/bads of delta conic hull?

http://sites.google.com/site/trojaninternational/Home/delta-conic-hull-design

IMO - the hull design was dropped in favor of cabin space. It went the way of the walk around. I like mine and prefer it to the more modern designs. It doesn't seem to wallow as bad and planes easier. The bow will also split a head wave with less bow rise and impact.

 

[nhmaina]

Re: What are the goods/bads of delta conic hull?

http://sites.google.com/site/trojaninternational/Home/delta-conic-hull-design

IMO - the hull design was dropped in favor of cabin space. It went the way of the walk around. I like mine and prefer it to the more modern designs. It doesn't seem to wallow as bad and planes easier. The bow will also split a head wave with less bow rise and impact.

Thank you. That was a nice writeup you forwarded me to. I am looking forward to trying out the boat, it's a Larson Citation DC 150.

 

[joe009]

Re: What are the goods/bads of delta conic hull?

i had the 19' dc,it was a good stable ride,but will pound in rough seas.good bay or lake boat.

 

[eastont]

Re: What are the goods/bads of delta conic hull?

I had a 250 Delta Cruiser and yes it did get up on plane quickly, but when I crossed another boats wake it would go up over the first wave then slam down on the next. The same was in rough seas with waves over 1 foot. The reason is the hull flattens out towards the stern and stops cutting through the water and rides on top.
My Carver is of a similar design and does much the same thing.

I've found with both boats that using the trim tabs to keep more of the bow in the water the slamming around was reduced.

 

[25thmustang]

Re: What are the goods/bads of delta conic hull?

I believe this design was on a lot of boats. Larson used the term to help sell boats, but I have seen it used on other designs as well. It looks like it would cut through the water pretty well, and to me is an attractive style.

Interesting note, the cabin space being lessened by the design. The Larson 250 is one of the very few boats in that size range that incorporated a dinette and a forward berth. I have never been in one to see how cramped it is, but rarely if ever do you see 25' boats with this layout.

 

[Grand Larsony]

Re: What are the goods/bads of delta conic hull?

I sold my 1989 Larson 250 San Marino last year (after having it for 7-8 seasons).

That boat was, indeed, about the BEST layout in any 25' express I've ever seen. The cabin was quite roomy and really does have two full beds (and a separate dinette, true standup head, etc.). Unusual for that size.

Best part was the wrap-around perimiter seating out back. Easy to fit 8-9 adults. Much more "social" than other boats.

Sorry to rave a bit there... the Delta Conic hull never gave me any problems and I liked it very much. Stable (and quiet, unlike my 300 Sundancer) at rest while sleeping, not bad in rough seas, and it did plane quickly. About the only compliant I could offer is it slammed into waves when crossing at an angle. Much better head-on.

 

[Grand Larsony]

Re: What are the goods/bads of delta conic hull?

Oh, two more things --

1. It wandered like CRAZY at idle speeds. Would not stay straight at all.

2. It required constant adjustment of the trim tabs. Even one adult moving around hte boat meant I had to push the buttons. Do it wrong, and the boat would really lay right over on it's gunnel.

 

[25thmustang]

Re: What are the goods/bads of delta conic hull?

Grand Larsony, The leaning over seems to be a trend with most narrow pocket cruisers. I have seen some driving down the river that look downright awkward laying over on their side.

Your Sundancer isn't quiet at rest while sleeping?

 

[nhmaina]

Re: What are the goods/bads of delta conic hull?

I sold my 1989 Larson 250 San Marino last year (after having it for 7-8 seasons).

That boat was, indeed, about the BEST layout in any 25' express I've ever seen. The cabin was quite roomy and really does have two full beds (and a separate dinette, true standup head, etc.). Unusual for that size.

Best part was the wrap-around perimiter seating out back. Easy to fit 8-9 adults. Much more "social" than other boats.

Sorry to rave a bit there... the Delta Conic hull never gave me any problems and I liked it very much. Stable (and quiet, unlike my 300 Sundancer) at rest while sleeping, not bad in rough seas, and it did plane quickly. About the only compliant I could offer is it slammed into waves when crossing at an angle. Much better head-on.

It sounds to me like the hull (in laymens terms) is somewhere between a standard V hull and a whaler tri hull in the way it acts. That was what I wanted, so it's perfect for me. I thought it may not be as good going through chop and another boat's wake. But I will take that tradeoff for the added stability and planing at lower speeds, which is, I believe, what you are saying I am getting. This one will be used on smaller lakes, but I would like to take it out on a calm day on the ocean, just close to shore though.

 

[This_lil_fishy]

Re: What are the goods/bads of delta conic hull?

Huh, so that's where my hull design comes from, except the flattened outter chine starts a bit further back (revised design?). As others have mentioned, my boat (a much smaller bowrider) is very stable at rest, tends to lean very little at full turn, but smacks waves real hard. In 1-3' chop I need to reduce speed and go bow high (bowrider, so I need to avoid scooping up water). Thinking about hitting a wave or wake on plane brings thoughts of serious back pain with it. That said, it planes early, and stays there longer at lower speeds. Fuel economy is real good, but it may be more the 4.3 engine then anything else.

I love my boat because it is so stable at rest, but I use it mostly as a fishing boat, skiers may not like it so much. Don't know how relative this is to a pocket cruiser..but had to add my two cents.

Ian

 

[nhmaina]

Re: What are the goods/bads of delta conic hull?

Just looked at your boat at http://www.boattest.com/oem/Boat-Test-OEM.aspx?id=1675&lp_id=366&p=0 , that is a REALLY nice boat. Maybe some day I can get me one of them

 

[This_lil_fishy]

Re: What are the goods/bads of delta conic hull?

Just looked at your boat at http://www.boattest.com/oem/Boat-Test-OEM.aspx?id=1675&lp_id=366&p=0 , that is a REALLY nice boat. Maybe some day I can get me one of them

Thank you, we didn't opt for the ski & fish package, so ours has a full bench at the back, with a larger upholstered sundeck. Also the bow seats are full wrap around seats not just the seat pads in the video. Without the live well the engine compartment is cavernous. I'm 6'2", and I work on the engine while comfortably sitting cross legged in there. It could use some engine compartment lights though.

This boat isn't packed with luxury features, but IS packed with convenience features.

We are super happy with this boat, even though we got the the 4.3V6 we still hit 47MPH (GPS) before I hit the rev limiter. Fuel economy is stunning, I am still using fuel from last year....just topped it up to give it some fresh fuel last weekend. I could use a taller prop, but I just haven't had the money due to the new baby. This is testament to the hull design I think, which brings us back on topic.

Ian

 

[nhmaina]

Re: What are the goods/bads of delta conic hull?

I know this is an old thread that I started, but I wanted to reply since I now have put at least a little time on my Larson 15' conic hull boat. I really like it. It's a 1988 so they don't make them anymore. I can't really compare them to current hull designs, I don't have a real deap V boat; But I will say that my previous boat had a "standar" fiberglass rounded hull and it would not cut through a wave, just rise up and slam down. This hull cuts through very nicely. It is also very stable in a tight turn, it takes much tighter turns than my previous boat and you don't feel like you are looking control of it in the turn. Probably helps that it's only 15' as far as turning is concerned. Really cuts through the water well. With 2 two passengers and a 50hp engine it comes up to planing in less than 5 seconds (didn't exactly time it, just an estimate). With 5 total passengers it takes a good 20 seconds to finally come up to planning. But that's a lot of weight for a 15' boat and 50hp so I consider that pretty good. Also, on windy days with slight chop on a small lake, it would plane at 35MPH without issue, i.e. no bouncing around. Really happy with the design and don't understand why they don't still make it. Again, I just thought I would post this in case others out there are curious.