sk16
New member
Does anyone know what the Vessel gross tonnage is for a Bayliner 285 (2003)? or can you direct me to somewhere that I might find this out?
Vessel gross tonnage
- Thread starter sk16
- Start date
Wiggo
New member
There is formula on the web somewhere. I presume you're after this for part 1 registration. If so, your surveyor may already know the answer.
Whitelighter
Active member
are you after it for P1 Registration? Or do you mean the weight?
Wiggo
New member
Gross Tonnage (GT) is a function of the volume of all ship's enclosed spaces (from keel to funnel) measured to the outside of the hull framing.
Tonnage measurements are now governed by an IMO Convention (International Convention on Tonnage Measurement of Ships, 1969 (London-Rules)), which applies to all ships built after July 1982. In accordance with the Convention, the correct term to use now is GT, which is a function of the moulded volume of all enclosed spaces of the ship.
It is calculated by using the formula : GT = K x V, where V = total volume in m³ and K = a figure from 0.22 up to 0.32, depending on the ship’s size (calculated by : K = 0.2 + 0.02 logV), so that, for a ship of 10,000 m³ total volume, the gross tonnage would be 0.28 x 10,000 = 2,800 GT.
Tonnage measurements are now governed by an IMO Convention (International Convention on Tonnage Measurement of Ships, 1969 (London-Rules)), which applies to all ships built after July 1982. In accordance with the Convention, the correct term to use now is GT, which is a function of the moulded volume of all enclosed spaces of the ship.
It is calculated by using the formula : GT = K x V, where V = total volume in m³ and K = a figure from 0.22 up to 0.32, depending on the ship’s size (calculated by : K = 0.2 + 0.02 logV), so that, for a ship of 10,000 m³ total volume, the gross tonnage would be 0.28 x 10,000 = 2,800 GT.
STEVEDUNSTABLE
Active member
after reading wiggo,s answer bet you wished you had,nt asked ! even steven hawkin could,nt work that out !.....good luck.
STEVEDUNSTABLE
Active member
i should,ve added i got less than 1 for sums at school
sk16
New member
Thanks for all the information so far. This is required for the Ship Radio licence application on the Ofcom site. I presume a rough guess of 3 would be OK for this use?
Wiggo
New member
I think 6 or 7 would be nearer the mark, actually. Think of it in terms of how much the boat would weigh if you completely flooded it. As an example, an 85' powerboat might weigh 50 tons (?) but the GT would be around the 200 mark.
geardownthreegreens
New member
My mates boss had a 30-31ft rinker which weighed in around 5.5 tons. I would put yours in around 4 ton.
But, i've just looked on boattest.com and it states 7241 lbs which is 3.29 tons. Bayliners are even lighter than i thought /forums/images/graemlins/grin.gif
Hope thats answered it for you.
But, i've just looked on boattest.com and it states 7241 lbs which is 3.29 tons. Bayliners are even lighter than i thought /forums/images/graemlins/grin.gif
Hope thats answered it for you.
Bajansailor
Well-known member
Steve Boerema of Viking Yachts (who make luxury sportsfishing boats in the USA) kindly supplied me last year with the info below from the USCG re calculating gross tonnages :
Gross Tonnage = (Hull Volume + Deckhouse Volume) / 100
But Deckhouse volume is ignored, since it's volume is less than that of the hull.
Hull Volume = S x K x L x B x D
Where L is Length on deck from bow to stern (excluding pulpits and swim platforms),
B is overall beam at the widest point of the hull (excluding rubbing strakes),
D is total hull depth amidships from hull bottom to weather deck (excluding the depth of the keel and any capping rails).
S is the Shape Factor, and is given as 0.67 for powerboats.
K is the Keel Factor, and is given as 1.0 for all hulls except sailboats.
Net Register Tonnage = M x GRT
where M is the Machinery Factor and is given as 0.8 for vessels NOT designed for sailing, with inboard propulsion machinery.
Gross Tonnage = (Hull Volume + Deckhouse Volume) / 100
But Deckhouse volume is ignored, since it's volume is less than that of the hull.
Hull Volume = S x K x L x B x D
Where L is Length on deck from bow to stern (excluding pulpits and swim platforms),
B is overall beam at the widest point of the hull (excluding rubbing strakes),
D is total hull depth amidships from hull bottom to weather deck (excluding the depth of the keel and any capping rails).
S is the Shape Factor, and is given as 0.67 for powerboats.
K is the Keel Factor, and is given as 1.0 for all hulls except sailboats.
Net Register Tonnage = M x GRT
where M is the Machinery Factor and is given as 0.8 for vessels NOT designed for sailing, with inboard propulsion machinery.
VicS
Well-known member
[ QUOTE ]
This is required for the Ship Radio licence application on the Ofcom site. I presume a rough guess of 3 would be OK for this use?
[/ QUOTE ] Yes a guess or at least an estimate is acceptable. You can always update it later if/when you find a more accurate figure.
I specifically asked Ofcom about this.
This is required for the Ship Radio licence application on the Ofcom site. I presume a rough guess of 3 would be OK for this use?
[/ QUOTE ] Yes a guess or at least an estimate is acceptable. You can always update it later if/when you find a more accurate figure.
I specifically asked Ofcom about this.
Refueler
Well-known member
[ QUOTE ]
Gross Tonnage (GT) is a function of the volume of all ship's enclosed spaces (from keel to funnel) measured to the outside of the hull framing.
Tonnage measurements are now governed by an IMO Convention (International Convention on Tonnage Measurement of Ships, 1969 (London-Rules)), which applies to all ships built after July 1982. In accordance with the Convention, the correct term to use now is GT, which is a function of the moulded volume of all enclosed spaces of the ship.
It is calculated by using the formula : GT = K x V, where V = total volume in m³ and K = a figure from 0.22 up to 0.32, depending on the ship’s size (calculated by : K = 0.2 + 0.02 logV), so that, for a ship of 10,000 m³ total volume, the gross tonnage would be 0.28 x 10,000 = 2,800 GT.
[/ QUOTE ]
Actually there are various Gross and Nett Tonnages and ships have more than one. What you quote is purely London Rule - it is not the only one. It is apparently trying to reconcile the different tonnages into one system Still to this day not achieved. Today GRT and NRT are still the figures entered on Ships Certificates - as we see in our work. But you are correct to say they are volume corrected figures and not related to actual tons / tonnes.
I can say this with reasonable feeling of being correct - conisdering that I deal with ships every day of my work.
To the original poster - for Ofcom applications it is not necessary to be exact with GRT for Radio licence (pleasure / private boat) as it's actually an invalid figure. Usual displacement is good enough.
Gross Tonnage (GT) is a function of the volume of all ship's enclosed spaces (from keel to funnel) measured to the outside of the hull framing.
Tonnage measurements are now governed by an IMO Convention (International Convention on Tonnage Measurement of Ships, 1969 (London-Rules)), which applies to all ships built after July 1982. In accordance with the Convention, the correct term to use now is GT, which is a function of the moulded volume of all enclosed spaces of the ship.
It is calculated by using the formula : GT = K x V, where V = total volume in m³ and K = a figure from 0.22 up to 0.32, depending on the ship’s size (calculated by : K = 0.2 + 0.02 logV), so that, for a ship of 10,000 m³ total volume, the gross tonnage would be 0.28 x 10,000 = 2,800 GT.
[/ QUOTE ]
Actually there are various Gross and Nett Tonnages and ships have more than one. What you quote is purely London Rule - it is not the only one. It is apparently trying to reconcile the different tonnages into one system Still to this day not achieved. Today GRT and NRT are still the figures entered on Ships Certificates - as we see in our work. But you are correct to say they are volume corrected figures and not related to actual tons / tonnes.
I can say this with reasonable feeling of being correct - conisdering that I deal with ships every day of my work.
To the original poster - for Ofcom applications it is not necessary to be exact with GRT for Radio licence (pleasure / private boat) as it's actually an invalid figure. Usual displacement is good enough.
JackBartlett
New member
How are lots of guesses from people who don't know the answer (and many of whom clearly don't understand the question) supposed to help this poor chap?
The most helpful answer was the one that someone cut and pasted from Wikipedia -- but I'm sure he could have googled that for himself!
The most helpful answer was the one that someone cut and pasted from Wikipedia -- but I'm sure he could have googled that for himself!
Wiggo
New member
OK, so our old Fairline Targa 28/29 had a GT of about 7 tonnes. It also displaced about 4 tonnes. Neither will be radically different for the Bayliner, I expect (+/-20%).
As it's for OfCom, those figures will be good enough.
As it's for OfCom, those figures will be good enough.
Tranona
Well-known member
Problem is that GRT is irrelevant for pleasure craft. It was originally used to determine port and light dues for commercial ships - and still is. However pleasure craft do not pay light dues and mooring fees (and harbour dues where levied) are usually based on length or in some cases area (L*B).
It is also irrelevant for a VHF licence as there is no legal requirement to fit one.
One can only assume it is laziness on the part of OFCOM to continue asking for it. Would they refuse a licence if it was not declared or a guess used?
It is also irrelevant for a VHF licence as there is no legal requirement to fit one.
One can only assume it is laziness on the part of OFCOM to continue asking for it. Would they refuse a licence if it was not declared or a guess used?
VicS
Well-known member
[ QUOTE ]
One can only assume it is laziness on the part of OFCOM to continue asking for it. Would they refuse a licence if it was not declared or a guess used?
[/ QUOTE ] It is one of the questions on the application form which has to be answered. I have no idea what the gross tonnage would be for my boat so I tried to leave the box blank but I could not proceed with the application so I put in the displacement. It was that that prompted me to seek the clarification from OFCOM that I mentioned earlier. I subsequently amended the licence details to a more realistic figure.
The justification for asking for this info is I believe, not laziness on the part of OFCOM, but that it is something they have to provide for SAR purposes, irrelevant though it may seem.
If you look at your details in the ITU Mars database you will see the registered tonnage is there at least if you have licensed under the new scheme of things.
A good idea to check your details there anyway! You might find someone else has your call sign, or you might find, like me that you are not listed at all. /forums/images/graemlins/mad.gif
http://www.itu.int/cgi-bin/htsh/mars/ship_search.sh
One can only assume it is laziness on the part of OFCOM to continue asking for it. Would they refuse a licence if it was not declared or a guess used?
[/ QUOTE ] It is one of the questions on the application form which has to be answered. I have no idea what the gross tonnage would be for my boat so I tried to leave the box blank but I could not proceed with the application so I put in the displacement. It was that that prompted me to seek the clarification from OFCOM that I mentioned earlier. I subsequently amended the licence details to a more realistic figure.
The justification for asking for this info is I believe, not laziness on the part of OFCOM, but that it is something they have to provide for SAR purposes, irrelevant though it may seem.
If you look at your details in the ITU Mars database you will see the registered tonnage is there at least if you have licensed under the new scheme of things.
A good idea to check your details there anyway! You might find someone else has your call sign, or you might find, like me that you are not listed at all. /forums/images/graemlins/mad.gif
http://www.itu.int/cgi-bin/htsh/mars/ship_search.sh
Tranona
Well-known member
Interesting. Not sure what use GRT would be in an SAR situation. Would have thought LOA and type of boat would be much more use.
VicS
Well-known member
Tells 'em how big it is. Type of boat is included.
Tranona
Well-known member
Just checked and my details, Name Call sign MMSI all correct but not GRT so I assume I registered (years ago) before it was a requirement, which is perhaps why I am displaying my ignorance! Anyway my boat is on the Part 1 so I have the Blue Book with all the detailed tonnage measurements so if required, I would be able to fill it in "accurately" unlike most people who will have to "guess".
Refueler
Well-known member
[ QUOTE ]
How are lots of guesses from people who don't know the answer (and many of whom clearly don't understand the question) supposed to help this poor chap?
The most helpful answer was the one that someone cut and pasted from Wikipedia -- but I'm sure he could have googled that for himself!
[/ QUOTE ]
I would hope you are not including my post in the "guesses" category - or did you mis-read my post ?
As I said there : I work with this rubbish every day and GRT / NRT is not valid for a plaesure boat usually - and Displacement is more commonly put on the form, as it's only valid number usually given by builders etc.
As to why Ofcom needs GRT ? It's a hang over from Ships - because it irks some boaters to think that there are others out there as well as pleasure boats !!
/forums/images/graemlins/wink.gif
How are lots of guesses from people who don't know the answer (and many of whom clearly don't understand the question) supposed to help this poor chap?
The most helpful answer was the one that someone cut and pasted from Wikipedia -- but I'm sure he could have googled that for himself!
[/ QUOTE ]
I would hope you are not including my post in the "guesses" category - or did you mis-read my post ?
As I said there : I work with this rubbish every day and GRT / NRT is not valid for a plaesure boat usually - and Displacement is more commonly put on the form, as it's only valid number usually given by builders etc.
As to why Ofcom needs GRT ? It's a hang over from Ships - because it irks some boaters to think that there are others out there as well as pleasure boats !!
/forums/images/graemlins/wink.gif
