a comunity designed self suporting vessel

In the U.S., at least, there's no upper limit on the number of passengers a pleasure yacht may carry; the only criterion to observe is that you don't charge for passengers to go aboard.

There is no statutory requirement for a U.S.-flag commercial or private vessel to be classed, nor are private yachts required to be inspected by the US Coast Guard.

Billionaires don't build yachts which are 150 meters long because they only want to host a few close friends aboard. Yachts like the Azzam or the Eclipse take dozens of crew to operate and probably are capable of hosting an equal number of guests, but details like this are usually not disclosed.

 

In the EU, the IMO definitions are respected.
A vessel designed to carry more than 12 passengers (regardless of whether they pay or not) is a passenger ship and has to be surveyed and certificated. A passenger is any person on board except children under 1 year of age, the Master, the crew and eventually a person appointed my the Master to take care of a passenger in need.

 

The above claim sounded oddly too different from the international practice, so I tried to dig some info about this issue.

I have found that there is a Passenger Vessel Safety Act dating back to 1993 which brought the US laws more in line with the international practice: http://www.uscg.mil/pvs/docs/PVSA_NVIC_7-94.pdf
So, above 12 pax, it calls the vessel "passenger ship", regardless of whether thay pay or not for the ride.

Passengers and non-passengers are defined in the pages 9-10 of the Passenger Vessel Service Act: https://www.cbp.gov/sites/default/files/documents/pvsa_icp_3.pdf

The only uninspected vessels are those who carry 6 passengers or less: http://www.uscg.mil/pvs/docs/UPV_GUIDEBOOK_under100GT_CGD11_2014.pdf

However, I am not an expert in the US legislation, so I might be wrong on all accounts of this issue.

 

Where the difference lays is in the definition of what a passenger is. Only a paying passenger qualifies. The rest can be considered crew or co-captains. That circumvents the maximum passenger rule.

 

Maybe it works differently in the US, but it is generally not so. It doesn't matter if the passenger pays or not. The term "passenger" is not a commercial term. Even if a person stays on board for free, he is a passenger if he is not part of the crew, or otherwise related to the vessel's operation.

The page 9 of the USCG Uninspected Passenger Vessel guidelines explicitly says:

All persons on board are crewmembers, passengers, or National Marine Fisheries Service official observers. THERE ARE NO GUESTS OR “OTHER” OBSERVERS.​

The SOLAS, which is valid only for ships operating on international routes but which has set the 12-pax standard, says:

A passenger is every person other than:
(i) the master and the members of the crew or other persons employed or engaged in any
capacity on board a ship on the business of that ship; and
(ii) a child under one year of age.​

How does the CG check if a person on board is effectively a member of the crew, that's somethig I ignore. It has to be proven with the paperwork, I guess. If they find 20 persons on the main deck suntanning, eating and sipping drink, they might have a legitimate doubt about them being a part of the crew... That would be quite an undisciplined crew.

 

The USCG has the burden of proof that the persons are passengers and not crew. If any person onboard declares to be crew, that is enough. The standard is about paying passengers rather than the activities.

 

Passenger, in any country, is anyone who has not assigned a specific task, related to the ship or its services, aboard.
Naturally, no one can decide for himself whether or not he is a passenger.
The attached picture is an extract of SOLAS 2009. I do not think the regulations in force in USA say otherwise.

 

In the US for US flag vessels, IMO and SOLAS apply only to those vessels engaged on an international voyage. If your vessel stays on domestic routes, you are obligated to follow only U.S. laws and regulations.

Regulation 3 of SOLAS contains a big exception for "Pleasure yachts not engaged in trade."

Such vessels are exempt from meeting SOLAS. Similar language can be found in the Load Line regulations. Pleasure yachts are not required to carry a load line.

 

Then we agree on everything, laws and regulations in force in the US do not say otherwise that SOLAS, but the clarification you do is relevant.
On the other hand, I think that here we are not talking of pleasure boats, at least me was talking about passengers ships and, therefore, what it is meant in those boats as "passenger".

 

Like those cited in my post #18, or some other regulations?

 

You are correct.

 

The PVSA of 1993 discusses cases where vessels are chartered, but as far as I can tell, the Act is silent on those vessels which are not operated on charter.

If you personally own and operate a pleasure yacht not on charter, the PVSA does not apply to you. If you put this vessel on charter to a third party, then you have to comply with the Act, under certain circumstances.

If you read Chart A, p. 11 or Chart B, p. 12, of the NVIC, if a vessel is not chartered, it is considered a Recreational Vessel and it may carry any number of passengers, as long as none of the passengers is carried for hire.

There are several other combinations of operational circumstances to consider, which is why the USCG developed Charts A, B, and C to simplify things.

 

Yes, you are right. I have found these two USCG documents where these conditions are summed up pretty clearly:

https://www.uscg.mil/hq/cgcvc/cvc/policy/policy_letters/CVC/CG-CVC_pol15-04.pdf

http://www.uscg.mil/d7/sectMiami/pdf/CharterBrochure.pdf

Thanks, cheers

 

Hi. I just want to give a concrete answer to your question from your other thread concerning how to scale.

If scaling length by factor s,
draft is also scaled by s.
Beam and freeboard are scaled by s^(2/3),
so displacement winds up being scaled by s^(2.667).

For scantlings (plate thickness, frame spacing, etc) see Elements of Boat Strength by Dave Gerr. Later in the design process make any adjustments the American Bureau of Shipping suggests.

In the full load condition - with as much weight aboard as you EVER expect to carry, full fuel tanks, supplies, provisions, cargo, passengers & crew, the ratio of freeboard to beam should be at least 1/6. That's to deck edge, not counting bulwark. The boat should be able to go over 60 degrees without down-flooding, through engine vents or anywhere else. And you'll need big engine vents as well as exhaust for that turbine! Many vessels with a stack bring the air in the sides of the stack, while the exhaust flues go up the center of the same generously sized stack and out the top.

Historic plans are available from Mystic Seaport at low cost: http://www.mysticseaport.org/research/collections/ships-plans/

Continuing a thought from your other thread: If you were to buy a crewboat you could sell the diesels (recouping some of your money), and repower with your turbine.

Another thought continued: you really should speak with Hawaiian naval architect Brian Trenhaile, http://hawaii-marine.com/templates/stability_article.htm. If you're carrying passengers FOR HIRE, you absolutely will need a naval architect working with you to meet Coast Guard requirements, laid out in 46 CFR. Here are some introductory guides: http://www.uscg.mil/pvs/SPV.asp If you intend to ferry passengers between two US ports, the hull MUST be US built because of the JONES ACT.

Be aware of four significant cutoff points in the regulations: 65 feet, 79 feet, more than 6 passengers, and 100 gross tons. Gross tonnage is not weight or displacement. One gross ton = 100 cubic feet of total enclosed volume.

Here are some marine (+other) gas turbine links:
http://www.yachtingmagazine.com/benefits-gas-turbine-engines
http://www.turbinemarine.com/
http://marineturbine.com/airboats/
https://www.vericor.com/marine-propulsion.html
https://www.researchgate.net/public...or_a_Pleasure_Boat_Theory_-_Project_-_Results
http://www.capstoneturbine.com/
http://www.bladonjets.com/
http://www.mtt-eu.com/
I think some boats have used the same turbine used in M1 tanks. Apparently that's the Honeywell AGT1500.
GE makes a range - not sure if the size or horsepower correlates with their names. One of them is the GE T58.