Perfect sized catamaran for ocean sailing is 40ft!

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Originally Posted by arsenelupiga

i was actually doing research today and found somewhere my claim. Cant find it anymore. Checking in wikipedia get this - so i am not clear about ball but cone holds.


https://en.wikipedia.org/wiki/Day_shapes



Where did you get your info ?

I can find two different versions of rule 25 (e):


https://www.law.cornell.edu/cfr/text/33/83.25

(e) A vessel proceeding under sail when also being propelled by machinery shall exhibit forward, where it can best be seen, a conical shape, apex downward. A vessel of less than 12 meters in length is not required to exhibit this shape, but may do so.


https://puc.overheid.nl/nsi/doc/PUC_2381_14/3/

(e) A vessel proceeding under sail when also being propelled by machiney shall exhibit forward where it can best be seen a conical shape, apex downwards.

Apparently (e) was revised at some point, but I am not sure, which one is current.

Paging @Dockhead:!

[Kev77]

This dude crossed the Atlantic in a 5ft 4 inch boat..

[Piscis]

I just checked the german collision regs. They do not mention the 12 Meter rule. So according to them (acctually they are just a translation of the intl. rules) the cone has to be shown in case motoring/motorsailing...

[contrail]

Originally Posted by Tupaia

So you have an ELECTRIC windlass - I rest my case.

Raising a fully battened mainsail bigger than 60sqm (about the norm for a 40ft cat, Lagoon 40 has 56sqm) is PITA for the smallest member of the crew. Monos tend not to have fully battened mainsails.

I suspect your boat has close to 80sqm main and I bet it is a real joy to raise manually. How often does your better half raise your mainsail on her own? I bet it is nearly always a task that you take on.

Anyway my point was to give a reference to the "rather outdated" reasoning behind the 40ft statement. It is not a rule just a very rough guide by defining the point at which a catamaran becomes more technical.

No one is saying that larger boats such as yours cannot be handled without mechanical aids they just become more demanding for the average sailor at around 40ft.

I certainly wouldn't say that a 40ft cat is the ideal size for ocean cruising.

Well, I singlehand a 46 footer, with a full battened mainsail of 923 sq feet. This is really a silly argument! i have actually had three different friends haul that mainsail up without even a winch. But, they are stronger than me, and probably stronger than you. The ideal size for anyone is a function of budget, size and physical ability of crew, and intended use. It is ridiculous to think that any two couples, or families, are the same. I am 72 but can run circles around many 50 year olds. Others, my age, are in nursing homes. All the personal factors depend. The physics, because resistance to capsize and pitchpole go up exponentially, suggests that 40 feet is the minimum size to take offshore, but plenty of smaller cats do it, and the physics don't suggest an upper limit. Frankly, I always thought 40 feet was pretty small, but I am now getting a 36 footer. Mostly to fit under bridges and in shallower water. Enjoy the boat you have....and hopefully, it is the best size for YOU.

[JasonS]

I always love these type of posts. They bring out the craziness and biases of so many. So I'll start by waving the white flag.

So we own a Manta 40, which actually has an LOA of 39'8". Right in the target range for this "perfect size" lol.

What we like about this size:
- Mast height is 61' with antennas/etc. Under 60 without. Most 40's are under 65' and are intracoastal friendly, allowing you to access anchorages/marinas/towns you can't in a larger boat
- Beam is 21'. Most 40's are in the 19-22' foot range allowing for a larger number of places to haul-out, and more slip/mooring availability. This is also true about 40' LOA and under.
- Ability for a couple to manage the boat. Recognize that many larger boats can be managed by 1-2 people. What I am referring to is many different things. For examples: Maintenance - the larger, the more daunting, including cleaning the bottom; "Manhandling" - Docking the boat in high cross winds and/or current conditions is doable with two people. The larger you go, the more difficult
- In general, large enough space for two people, plus significant gear (we carry two kayaks, two paddleboards, 4 scuba tanks, significant scuba gear, a Brownies Hookah System, a sailrite sewing machine, along with lots of tools, spares and other hobby items, etc). Also, enough space for easy provisioning for 2+ months and a large galley.
- Enough real estate for solar. We have 3 x 375 watt solar panels on top with little shading.
- Amenities! Large enough for 2 air-conditioners, a decent sized diesel generator, and a well appointed galley
- Performance - In general, performance is reasonable for 40 foot cats, regularly sailing at 5-9 knots depending on wind/wind angle, and capable of faster speeds. Cruising on 1 motor at 4.5-6.5 knot avg and 2 motors at 5.5-7.5 knot avg, for about 3/4 gallon to less than 1.5 gallon/hr.

So, why would we want a larger boat?
- Smoother, faster if we were to make a circumnavigation or multiple transatlantic/pacific crossings
- Ability to have a decent sized scuba compressor on the boat. The small scuba compressors are NOT worth having! The costs of operation/filters/time to fill a tank make them a no go in our view
- More room... sometimes my better half just wants more space!

So, why would we want a smaller boat?
- We wouldn't!

In the end, your finances, and your given lifestyle choices should dictate what the "perfect-sized" catamaran is for you. And keep in mind, a 50' performance cat like an Outremer or Gunboat may have the same, or even less, usable space as a 40' cruising cat. And the performance cats are more sensitive to large amounts of weight being added. And maintenance time/costs are proportionally larger as you increase size.

My recommendation to those looking is always visit lots and lots of boats, both new and used, at boat shows and through brokers and individuals. Ask questions of owners.

AND IMPORTANTLY - Have a really good idea of HOW you want to cruise for the next 3+ years. If your goal is to stay in the Bahamas/Caribbean/US East Coast, size is a comfort factor more than anything. And mast height can be an important consideration for Intracoastal cruising. If you want to circumnavigate, going slightly larger may provide a speed and/or comfort advantage with a smoother ride.

MOST IMPORTANT - Live your dream. I'd rather be on a small (but safe) boat, then living on land.

See you on the water!

[Tomodore]

I have been sailing for 30 years and the majority of sailors I have met feel their boat is the perfect size, right up to the time they upsize, downsize or move to power. It used to be if you had a roller fueling headsail you were not seaworthy because of new technology. Now it seems some folks feel an electric winch is a problem. Systems on boats are always in need of attention, I have found that if I keep the water out and the mast up I can find a work around for the rest. It helps to be lucky, handy and rich, in that order.
Opinionated Sailor

[Kev77]

Originally Posted by JasonS

I always love these type of posts. They bring out the craziness and biases of so many. So I'll start by waving the white flag.

So we own a Manta 40, which actually has an LOA of 39'8". Right in the target range for this "perfect size" lol.

What we like about this size:
- Mast height is 61' with antennas/etc. Under 60 without. Most 40's are under 65' and are intracoastal friendly, allowing you to access anchorages/marinas/towns you can't in a larger boat
- Beam is 21'. Most 40's are in the 19-22' foot range allowing for a larger number of places to haul-out, and more slip/mooring availability. This is also true about 40' LOA and under.
- Ability for a couple to manage the boat. Recognize that many larger boats can be managed by 1-2 people. What I am referring to is many different things. For examples: Maintenance - the larger, the more daunting, including cleaning the bottom; "Manhandling" - Docking the boat in high cross winds and/or current conditions is doable with two people. The larger you go, the more difficult
- In general, large enough space for two people, plus significant gear (we carry two kayaks, two paddleboards, 4 scuba tanks, significant scuba gear, a Brownies Hookah System, a sailrite sewing machine, along with lots of tools, spares and other hobby items, etc). Also, enough space for easy provisioning for 2+ months and a large galley.
- Enough real estate for solar. We have 3 x 375 watt solar panels on top with little shading.
- Amenities! Large enough for 2 air-conditioners, a decent sized diesel generator, and a well appointed galley
- Performance - In general, performance is reasonable for 40 foot cats, regularly sailing at 5-9 knots depending on wind/wind angle, and capable of faster speeds. Cruising on 1 motor at 4.5-6.5 knot avg and 2 motors at 5.5-7.5 knot avg, for about 3/4 gallon to less than 1.5 gallon/hr.

So, why would we want a larger boat?
- Smoother, faster if we were to make a circumnavigation or multiple transatlantic/pacific crossings
- Ability to have a decent sized scuba compressor on the boat. The small scuba compressors are NOT worth having! The costs of operation/filters/time to fill a tank make them a no go in our view
- More room... sometimes my better half just wants more space!

So, why would we want a smaller boat?
- We wouldn't!

In the end, your finances, and your given lifestyle choices should dictate what the "perfect-sized" catamaran is for you. And keep in mind, a 50' performance cat like an Outremer or Gunboat may have the same, or even less, usable space as a 40' cruising cat. And the performance cats are more sensitive to large amounts of weight being added. And maintenance time/costs are proportionally larger as you increase size.

My recommendation to those looking is always visit lots and lots of boats, both new and used, at boat shows and through brokers and individuals. Ask questions of owners.

AND IMPORTANTLY - Have a really good idea of HOW you want to cruise for the next 3+ years. If your goal is to stay in the Bahamas/Caribbean/US East Coast, size is a comfort factor more than anything. And mast height can be an important consideration for Intracoastal cruising. If you want to circumnavigate, going slightly larger may provide a speed and/or comfort advantage with a smoother ride.

MOST IMPORTANT - Live your dream. I'd rather be on a small (but safe) boat, then living on land.

See you on the water!

Spot on

[Kamen]

Originally Posted by contrail

The physics, because resistance to capsize and pitchpole go up exponentially, suggests that [...]

Are you sure? I don't think the righting moment goes up exponentially. Pretty sure it is a polynomial (of 4th degree) function of the linear dimension. Mass goes up with the cube of the linear dimension and the leverage is linear with respect to size.

[cat-keys]

40ft is perfect for a couple I agree. My wife and I have leopard 40 space is tremendous even with guests. Also the beam in our cat is 21ft only which makes it narrow enough to fit into 50ton travel lifts here in SFL giving us many more haul out options.

In our experience the bigger the boat the more systems the more maintenance the higher the expense. We’d rather save the money and spend it on extending our cruising

Often we have dreamed about 50ft range for transoceanic like Knysnas or St Francis but for our plans to island hop the caribbean in shallow water 40ft seems optimal

[OneKoolCat]

I am in the same category as JasonS.

Mine is a 40 so I agree!

All boats are great ocean going boats and all of them have problems. If there is a perfect boat it is probably too expensive for me. I am always single handing. If you add an electric winch or 2, maybe a self tacking jib. Suddenly a large cat is more manageable. Know your boat and her performance and pick your windows.

Cheers,
Peter

[arsenelupiga]

Originally Posted by Piscis

I just checked the german collision regs. They do not mention the 12 Meter rule. So according to them (acctually they are just a translation of the intl. rules) the cone has to be shown in case motoring/motorsailing...

here you go

link

https://puc.overheid.nl/nsi/doc/PUC_2381_14/3/

Rule 27 Vessels not under command or restricted in their ability to manoeuvre

(g) Vessels of less than 12 metres in length, except those engaged in diving operations, shall not be required to exhibit the lights and shapes prescribed in this Rule.


But then in
Rule 30 Anchored vessels and vessels aground
(a) A vessel at anchor shall exhibit where it can best be seen:
(i) in the fore part, an all-round white light or one ball;



wtf, how can one follow if rules are not even clear

[blubaju]

Hm, I'd start with 80cm or 2.6ft bridge deck clearance or you'll end up in an uncomfortable ride.

[arsenelupiga]

Originally Posted by blubaju

Hm, I'd start with 80cm or 2.6ft bridge deck clearance or you'll end up in an uncomfortable ride.

that is definitely consideration comfort and structure stress.

however there is more than 1 way to skin the cat.

on one side you have thin hulls high bridgedeck. Works great until seas are really up. this type of boats display side instability in such conditions. Thin hulls and high bridgedeck allow large side swings.

wide hulls smaller bridgedeck and nacelle, receipe of condomarans works as well without instability. Reason is as hulls are wider, bridgedeck is narrower and needs less height to achieve same level of efficiency as thin hulls high bridgedeck.

[Paul Howard]

I owned a 39ft catamaran for 16 years, doing 7years of full time cruising during that time, about 60,000nm, mostly with just my wife and I onboard.
We occasionally had 2 or 3 guests onboard with us for up to 6 weeks at a time, friends and family and never wanted someone along as necessary crew. We made passages up to 3,300nm, 20 days, with just the two of working the boat without a problem.
I never felt the boat was too small and never wanted a larger boat.
In my mid-70's I downsized to a light 38ft catamaran and like it very much.

[Chris Cringle]

NO! And be careful here. The perfect size for an offshore Catamaran is 40 feet, 3 3/16 inches. Get it right! A tiny bit too long or too short will doom your cruise.