Quickstep192
Super Anarchist
Are there any J/46 Owners here who know the gross tonnage of a J/46?
I’d sure appreciate the number if someone has it on their documentation.
I’d sure appreciate the number if someone has it on their documentation.
J/46 Tonnage - any J/46 owners who know?
- Thread starter Quickstep192
- Start date
slug zitski
Banned
- Banned
- #2
Odd for a private yacht …tonnage certificate
Ask j boat for numbers
Ask j boat for numbers
https://www.dco.uscg.mil/Portals/9/...ied Measurement.pdf?ver=2017-06-09-123757-680
This is the USCG guide to gross tonnage.
This is the USCG guide to gross tonnage.
slug zitski
Banned
- Banned
- #8
Tonnage is a cargo carrying number
Free Interior volume…. ability to carry cargo
A commercial registration has one
Free Interior volume…. ability to carry cargo
A commercial registration has one
hols on now Sluggo. You ever captain a US registered wessel? All of our little CG documented boats have a "tonnage" number. Even my little 43'er.
Quickstep192
Super Anarchist
- Thread starter
- #11
Sweet! Thank you!!
Quickstep192
Super Anarchist
- Thread starter
- #12
I found another J/46, bit this one shows gross tonnage as 15.
Any idea why they’d be different?
Any idea why they’d be different?
Chrick
New member
As to why one would be 21 and the other 15 tonnes: I know when I registered my J/44 I calculated it myself, and I'm sure that someone else calculating it for my boat could have come up with a substantially different number.
The 44 has the same hull as the 46 minus the swim scoop, so if I got it right it should be mostly right for a 46. I may have gotten it wrong, however!
The 44 has the same hull as the 46 minus the swim scoop, so if I got it right it should be mostly right for a 46. I may have gotten it wrong, however!
Different formulas. Canadian metric tonnage 
Actually USCG simplified tonnage formula = L x B x D x hull factor (feet) / 100. For sailboats hull factor is 0.5
Canadian calculation = L x B x D x 0.08 in metres with 0.08 hull factor for fin keel sailboats
So 13.69x4.18x3.62x0.08 = 16.57
The Canadian rule includes the depth of the keel (3.62 = 11.9') while the USCG does not for fin keel boats.
While cruising, in a few international ports, we had to pay port fees based on tonnage. So a LOW tonnage is good. These fees were not significant however as they are designed with cargo ships in mind.
And don't get me started on Panama Canal tonnage or Suez Canal tonnage which are also determine how much your ship pays to go through. These use their own formulas....
In the US (for commercial vessels) there are all sorts of exemptions to reduce your tonnage. Wide passages, not weathertight openings, etc. etc. A huge industry has arisen to take advantage of this. So a 200 T vessel in the US will be 500 T in the rest of the world.
Actually USCG simplified tonnage formula = L x B x D x hull factor (feet) / 100. For sailboats hull factor is 0.5
Canadian calculation = L x B x D x 0.08 in metres with 0.08 hull factor for fin keel sailboats
So 13.69x4.18x3.62x0.08 = 16.57
The Canadian rule includes the depth of the keel (3.62 = 11.9') while the USCG does not for fin keel boats.
While cruising, in a few international ports, we had to pay port fees based on tonnage. So a LOW tonnage is good. These fees were not significant however as they are designed with cargo ships in mind.
And don't get me started on Panama Canal tonnage or Suez Canal tonnage which are also determine how much your ship pays to go through. These use their own formulas....
In the US (for commercial vessels) there are all sorts of exemptions to reduce your tonnage. Wide passages, not weathertight openings, etc. etc. A huge industry has arisen to take advantage of this. So a 200 T vessel in the US will be 500 T in the rest of the world.
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