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Demystifying yacht classification A, B, C, D

N.B. For your information, a more recent article was published on 24 Oct 2022 on the same subject, click here for direct access.

Beaufort_wind_scale

Demystifying yacht classification :  Class A, B, C and D

Since 1998, CE certification is required for all recreational boats entering or being sold in Europe obliging boat manufacturers to respect certain building and security standards.  Therefore, yachts ( boats ) are classified into four categories depending on their aptitude to confront navigational conditions taking into account both force of the wind and height of the waves.  The categories are not to limit the area and distance of navigation (that is defined by security equipement onboard) but  to  sensitize the owner and/or captain of the boats capacities to navigate in complete security.

Let us start with the Beaufort Scale.   A scale for classifying the force of the wind ranging from 0 (calm) to 12 (hurricane).   It was devised by an admiral in the British Navy, Francis Beaufort, to uniform the description of the effect of different winds at sea.

There is a direct link between the Beaufort scale and boat classification.   For discussion purposes, we will use only the 6, 7 and 8 forces.

A Class A yacht ( boat ) is a vessel that is built to navigate the open ocean and surpass a force 8 on the Beaufort scale and surpass waves higher that 4 meters.   These yachts are constructed to be self sufficient in hostile seas.

A Class B yacht ( boat ) is a vessel built to navigate on the offshore waters (200 miles and less) and can substain UP TO force 8 and waves UP TO 4 meters.

A Class C boat is a vessel built to navigate inshore such as lakes, rivers, bays and close to the shore and can sustain UP TO force 6 and waves UP TO 2 meters.

A Class D boat is built for protected or sheltered waters such as canals, rivers, small lakes and sustain a force 4 and waves UP TO .3 meters (less that 1 ft).

With this said, you can understand that the Class A yacht ( boat ) respects a rigorous building code more so than a Class B and so forth.    But regardless of the class, it is strongly discouraged to navigate in a force 7 for the reasons of safety and comfort as « pleasure » should always be on the agenda.  Always consult the weather forecast prior to leaving any port and check hourly the weather situation.

Classification is very important and should be on your question list before purchasing any boat or yacht.

Classification rules are developed to assess the structural strength and integrity of the essential parts of the hull, the reliability and function of the propulsion, steering systems, power generation and all the other features installed on board which contribute to guarantee the main essential services of yacht.

Also for a class A, the portholes will be more resistant against a sustained wave, the drains to evacuate the water more abundant and of good size, the joints of the hull more hermetic, in short everything is in place to prevent water from s’ infiltrate on board.

By way of information, let us quote for example all the Ferretti yachts (60 to 96 feet), Pershing (60 to 115), the Riva (44 to 122) are all of class A just like the Magellano range at Azimut including also the 66 Flybridge.

Ferretti yachts (500, 550, 670 fly and over), Pershing (7X and over), Azimut Yachts (62, 64, 66, 68 Fly and over, the Sport Series 7X and over, all Magellano) are Class A.  There are also other classifications such as RINA and American Bureau of Shipping, Bureau Veritas, Det Norske Veritas, Germanischer Lloyd, Lloyd Register, that are more precise regulations and we will cover this later in another article.

Below is the graph of the Beaufort Scale along with photos.

Do not hesitate to contact us for any additional information, team Ita Yachts Canada is at your disposal.

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Allied Yachting

Class Notations on Yachts – Classification Guide

9 December 2016

INTRODUCTION TO YACHTS CLASSES

Classification.

Rules are developed to establish standards for the structural strength of the large yacht’s hull and its appendages, and the suitability of the propulsion and steering systems, power generation and those other features and auxiliary systems which have been built into the ship to assist in its operation, and even pollution protection systems. A yacht may be maintained in class provided that, in the opinion of the Society concerned, it remains in compliance with the relevant Rules, as ascertained by a periodic or non-periodic survey(s). Today a vessel either meets the relevant Class Society’s Rules or it does not. As a consequence, it is either “in” or “out” of “Class”.

In summary, Class Notations on Yachts will tell you a lot about the building quality and condition of each vessel and its components on an annual basis, according to the excellence of its construction and its adjudged continuing soundness. A yacht that has been designed and built to the appropriate Rules of a Society may apply for a Certificate of Class from that Society or for a periodical survey (generally required every 5 years) meant for the Renewal of Class Certificate . Class Societies have often developed two separate sets of Rules for Commercial and Private Yachts . They can be applied to New Construction as well as Existing Yachts .

Classification Societies

Classification Societies play a fundamental role in today’s marine industry. A Society will act on behalf of ship-owners and builders to ensure high build quality and the safety of a ship’s main structural parts . Classification also provides a point of reference with regard to those who were involved in the supply chain including builders, charterers and insurers.

As an independent, self-regulating, externally audited, body, a Classification Society has no commercial interests related to ship design, shipbuilding, ship ownership, ship operation, ship management, ship maintenance or repairs, insurance, or chartering.

The process begins with the design and construction phases, focussing on the implementation and manufacture of key components as well as technical specifications. The standards which must be adhered to are dictated by the regulations of the chosen society and are published as rules, evolving continuously to incorporate new technologies and client requests via the advice of highly competent engineers and architects.

All Classification Societies waive liability for future faults as a surveyor can only record a vessel’s quality at the time of inspection; it is then the responsibility of the yacht owner to maintain the vessel and inform the society in the event of damage or structural alteration. Although the surveys are thorough, they do not cover all aspects of a ship’s build and operating service. This can include crew qualifications, navigational aids and manoeuvrability.

Classification Societies are often simply referred to as “Class Societies” or just “Class”. There are currently 13 members of the International Association of Classification Societies (IACS) , each with a unique set of rules, classification layouts and notations. Five of the biggest Classification Societies are listed below, along with their identifying signature, to denote a ship constructed under special survey in compliance with the Society’s rules, suitable for unrestricted sea-going service:

The marks following the Society’s standard signature are not interchangeable between organizations, meaning each letter or number will represent a different characteristic for each society. Each mark can be broken down to highlight a yacht’s capabilities, equipment or restrictions.

Each of the Classification Societies has developed a series of notations that may be granted to a vessel to indicate that it is in compliance with some additional voluntary criteria that may be either specific to that vessel type or that are in excess of the standard classification requirements.

The Classification of a yacht does not absolve the Interested Party from compliance with any requirements issued by Administrations and any other applicable international and national regulations for the safety of life at sea and protection of the marine environment such as SOLAS, ILLC, MARPOL, ILO or IMO.

Smaller vessels are categorized differently, adhering to different requirements and statutory regulations. With a heavier focus on passenger numbers and distance of operation from shore, the Maritime and Coastguard Agency (MCA) outlines guidance for UK vessels (up to 24 meters in length) which are used for charter or commercial use.

As RINA is today the most reputed Classification Society in the Mediterranean and a leader in the yachting certification business, developing and offering services of ships classification, certification, verification of conformity, inspection, and testing, we will hereby provide you with a summary of their more common Class Notations on Yachts , this will be helpful to identify these most peculiar symbols :

CLASS NOTATIONS – RINA

Main class symbol.

The main class symbol C is assigned to ships built in accordance with the requirements of the Rules or other rules recognized as equivalent and maintained in a condition considered satisfactory by the Society. The period of class (or interval between class renewal surveys) assigned to a ship is a maximum of 5 years.

Except for special cases, a class is assigned to a ship only when the hull, propulsion and auxiliary machinery installations, and equipment providing essential services have all been reviewed in relation to the requirements of RINA’s Rules.

With the 5 year class period is to be understood as being the highest class granted by the Society.

Construction Marks

The construction mark identifies the procedure under which the yacht and its main equipment or arrangements have been surveyed for the initial assignment of the Class.

Construction marks defined below are assigned separately to the hull of the yacht and its appendages, to the machinery installation.

The construction mark is placed before the symbol HULL for the hull, before the symbol MACH for the machinery installations, and before the additional Class Notation granted, when such a notation is eligible for a construction mark.

When the same construction mark is assigned to both hull and machinery, the construction mark is assigned globally to the ship without indication HULL and MACH after the main class symbol.

Hull Construction Mark (HULL)

  • Construction mark ✠ is assigned to the hull when it has been surveyed by RINA during its construction in compliance with the new building procedure.
  • Construction mark ✠ is assigned to the hull when it was built under the survey of another Society.
  • Construction mark ● is assigned to the hull in all cases other than those listed above.

Machinery Construction Mark (MACH)

  • The construction mark ✠ is assigned when the propelling and auxiliary machinery has been designed, constructed, certified, installed and tested in accordance with RINA Rules.
  • The construction mark ✠ is assigned when the propelling and auxiliary machinery has been designed, constructed and certified in accordance with the rules of another society and installed and tested under the survey of RINA.
  • Construction mark ● is assigned in all cases other than those listed above.

Navigation and Operating Notations

The navigation notation UNRESTRICTED NAVIGATION is assigned to a ship intended to operate in any area and any period of the year.

Restricted operating area notations are optional and will be marked accordingly like, for example, on a specified operating area or operation service within “x” miles from shore.

Additional Class Notations

An additional Class Notation expresses the classification of additional equipment or specific arrangement, which has been requested by the Interested Party. The assignment of such an additional Class Notation is subject to the compliance with additional rule requirements.

Some additional Class Notations, due to the importance of relevant equipment or arrangements, are assigned a construction mark. This is indicated in the definition of the relevant additional Class Notations. Class Notations which may be assigned to a ship are listed according to the category to which they belong:

Automated Machinery Systems (AUT)

AUT notations are relevant to automated machinery systems installed onboard ships.

Automated machinery systems (AUT – UMS (Y))

The additional Class Notation AUT-UMS (Y) may be assigned to yachts that are fitted with automated installations enabling machinery spaces to remain periodically unattended in all sailing conditions including manoeuvring.

Integrated Ship Systems (SYS)

SYS notations are relevant to the operation of integrated systems regarding navigation, machinery, communication and specific cargo, as applicable.

Centralised Navigation Equipment (SYS-NEQ)

The additional Class Notation SYS-NEQ is assigned to yachts which are fitted with a centralized navigation control system so laid out and arranged that it enables normal navigation and manoeuvring operation of the ship by two persons in cooperation.

Centralised Navigation Equipment (SYS-NEQ-1)

The additional Class Notation SYS-NEQ-1 is assigned when, in addition to the above, the installation is so arranged that the navigation and manoeuvring of the yacht can be operated under normal conditions by one person, for a periodical one-man watch. This notation includes specific requirements for the prevention of accidents caused by the operator’s unfitness.

Integrated Bridge System (SYS-IBS)

The additional Class Notation SYS-IBS is assigned to yachts which are fitted with an integrated bridge system which allows simplified and centralized bridge operation of all main functions of navigation manoeuvring and communication, as well as monitoring from the bridge of other functions related to specific cargoes and pollution; for passenger ships, heating, ventilation and air conditioning are also included in the monitored functions

Communication System (SYS-COM)

The additional Class Notation SYS-COM is assigned to yachts which are fitted with a local area network including the alarm, monitoring and control systems and computers used for management operations and external communication devices for reporting ashore navigation, maintenance and operational information.

Damage Stability (DMS)

The additional Class Notation DMS may be assigned to yachts complying with the damage stability requirements.

STAR Notation

General STAR is a System of Trace and Analysis of Records integrating rational analysis with data and records from ship-in-service concerning planned inspection and ship maintenance.

The additional Class Notation STAR-HULL is assigned to ships on which an Inspection and Maintenance Plan (IMP) for the hull is implemented.

The notation may be completed by the suffix NB when a structural tridimensional analysis has been performed for the hull structures, at the new building stage. The suffix NB is removed when the ship enters the STAR-HULL survey program through the implementation of the Inspection and Maintenance Plan (IMP).

The additional Class Notation STAR-MACH is assigned to yachts on which an Inspection and Maintenance Plan (IMP) for the machinery is implemented. This plan is based on a risk analysis review of the installation.

STAR Notation (STAR)

When yachts are granted both STAR-HULL and STAR-MACH, the two separate notations are superseded by the cumulative additional Class Notation STAR.

Crew Accommodation and Recreational Facilities (MLCDESIGN)

According to the Maritime Labour Convention 2006 Notation:

The additional Class Notation MLCDESIGN is assigned to yachts having crew accommodation and recreational facilities complying with the Maritime Labour Convention 2006 (MLC).

GREEN PLUS Notation (Eco-Friendly Yachts)

Issued in 2008 and updated yearly, the GREEN PLUS additional Class Notation has been revised in 2012 to cover new issues for seagoing ships and ships operated at a fixed location. The additional Class Notation GREEN PLUS is assigned to Eco-Friendly yachts compliant with the Society’s environmental protection framework of airborne gases, spillage/leakage of substances, oil, sewage, greywater, garbage disposal and noise mitigation systems to prevent pollution.

Safety Class Notation EFP (Bureau Veritas)

The following additional Class Notations are assigned to yachts complying with the requirements of this Section:

  • EFP-A : for yachts having Enhanced Fire Safety Protection in accommodation spaces,
  • EFP-M : for yachts having Enhanced Fire Safety Protection in machinery spaces,
  • EFP-C : for yachts having Enhanced Fire Safety Protection in cargo areas,
  • EFP-AMC : for yachts complying with all the requirements of this Section.

For more information on Class Notations on Yachts – Classification of Yachts , please feel free to contact Allied Yachting .

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Classification: Statutory certification explained

Is certification an unnecessary complication, the costs and hassle of which far outweigh the benefits, or a helpful and reassuring framework which sets the highest standards for structural and operational safety and safeguards life, property and the sea environment?

No one could possibly deny that the large yacht industry is, and has been for some time, in the throes of a boom in spite of a recent downturn since 2008. Some observers would suggest that this is in spite of all the new rules and regulations that seem set to dog the yacht owner’s every move. Others would suggest that it is through the introduction of rules and regulations such as the MCA’s Code of Practice for Safety of Large Commercial Sailing and Motor Vessels that the industry has been given the confidence to expand with such vigour, knowing that their investments are safer – both financially and physically – because of regulation.

Classification societies are non-governmental organisations or groups of professionals, ship surveyors and representatives that develop, publish and certify standards and technical rules to ensure an acceptable degree of stability, safety and environmental impact, among other things. They are authorised to certify yachts and vessels flagged virtually anywhere.

A classification certificate attests that the yacht complies with the standards developed and published by the issuing society

New construction and refit surveys carried out by a surveyor from the classification society under which the yacht is built are important inspections that take place at intervals throughout the duration of the project. They ensure that any and every installation, repair, upgrade or modification is carried out to the standards of that society. Classification surveyors are interested in the structural integrity of the hull, installation of equipment, stability, structural, engine and machinery surveys, electrical, electronic and ancillary equipment, rigging inspections, safety recommendations and ultrasonic thickness gauging.

Every owner has his own vision of what he wants his yacht to be and designers strive to deliver just that. The fulfillment of this vision in turn becomes paramount in the eyes of the building yard and others who represent the owner, so it is often the policies imposed in the form of building regulations and classification rules that act as the voice of reason. This ultimately allows a balance to be struck between the attainment of that vision and the safety and reliability embodied in the construction of a yacht built to class.

A classification certificate attests that the yacht complies with the standards developed and published by the issuing society. Periodic surveying of a yacht in service by the appropriate class surveyor, at intervals dictated by the appropriate classification society, is also required to ensure the vessel continues to meet the rules and thus maintain her in-class status. Should any defects that may affect class become apparent, or if damage is sustained between surveys, the owner or operators are required to inform the society concerned without delay.

Almost every yacht that is launched is bigger or in some way better than the last and, quite often, more complex than its predecessor

As independent, self-regulating bodies, classification societies have no commercial interest in design, building, ownership, operation, management, maintenance, repairs, insurance or chartering. Classification rules are not intended as a design code and, in fact, cannot be used as such. These are more generally covered by the flag state, which lays down standards, or codes of practice that dictate construction good practice.

Almost every yacht that is launched is bigger or in some way better than the last and, quite often, more complex than its predecessor. As this trend continues, so too is the involvement and role of classification societies increasing and evolving. But what exactly does classification entail, and how is it linked to the statutory requirements of the various flag states? These matters are often misunderstood, which can potentially result in a conflict of responsibility.

Classification

The classification process The classification of yachts may be regarded as the development and worldwide implementation of published rules and regulations which – in conjunction with proper care and conduct on the part of the builder, owner and operator – provides for the structural strength and, where necessary, the watertight integrity of the hull. The same rules cover any appendages to the hull itself.

Classification rules lay down regulations that govern the effectiveness, safety and reliability of the propulsion and steering systems and other features, as well as the auxiliary systems which establish and maintain basic conditions on board and ensure that guests and crew can be safely carried while the yacht is at sea, at anchor, or moored inside a harbour.

Owners sometimes see classification as an unnecessary complication offering no real advantage for the cost. Some even suggest that the classification societies exist simply to make a profit out of a yacht builder’s desire to build a saleable product.

‘This is a misconception and one that needs to be addressed,’ Paul Martin, a principal engineer at DNV, points out: ‘Classification societies are independent bodies without a commercial stake in the build, and are therefore in a unique position to make sure that the yacht meets requirements without considering commercial impact. This enables yachts to be built with safety of the yacht, her crew, other vessels and the environment given maximum priority, irrespective of cost.’

Owners sometimes see classification as an unnecessary complication offering no real advantage for the cost

‘Because most classification societies have enormous experience,’ he continues, ‘as well as a lot of data on the failure of various types of vessels, machinery and other connected disciplines, they can bring these to bear on new projects ensuring fees are justified, and at the same time enhancing safety against the most up-to-date maritime knowledge and good safe practice.’

Yachts are said to be ‘in class’ when the classification society believes that its rules and regulations have been complied with, unless it has granted a special dispensation from compliance for a particular aspect. In order to decide whether a vessel should achieve in-class status surveyors appraise design, surveys and reports on the vessel’s construction, machinery, apparatus, materials, components, equipment, production methods and processes of all kinds for the purpose of verifying their compliance with plans, specifications and rules, codes of practice, or their fitness for particular requirements.

Class surveyors can also provide other technical inspection and advisory services relating to yachts and maintain these provisions during periodical visits to ascertain that the vessel is complying with classification society regulations at all times. Any modification which would affect class must always receive prior approval by the society.

When a yacht is going to be built to class, construction plans and all particulars relevant to the hull, equipment and machinery have to be submitted for the society’s approval before the work commences. Subsequent modifications or additions to the scantlings, arrangements or equipment shown on the approved plans must also be submitted for appraisal.

Implementation Statutory aspects deal with issues such as stability, life-saving appliances, pollution prevention and structural fire protection. Generally there are quite clear dividing lines between class and statutory requirements, although there are a few exceptions.

Flag states

The flag state, or nationality, of a yacht is important because it controls which country has the right to prescribe and enforce laws governing her operation. A ship must sail under the flag of a single state. The most common method by which a ship is granted the nationality of a state is by formal registration of the ship with that state.

Upon registration the ship acquires rights and duties as a result of registration which vary depending upon the state and the conventions and treaties to which it is party.

The rights will normally include action in an international court if there is a violation of international law against the vessel by another state, and representation at international conferences and organisations.

The duties include the upholding of the law of the flag state aboard the vessel, wherever she may be in the world.

Quality flags will also provide a recognised reputation for excellence, helping the vessel to avoid lengthy Port State Control inspections in foreign ports, and give worldwide support from embassies and consuls of that state and the protection of its navy.

International Maritime Organization

Statutory regulations are not only produced by the marine administrations of countries, but also the International Maritime Organization (IMO).

While some marine or flag administrations have the ability and knowledge to produce their own legislation, this is not true for the majority of countries. As shipping is an international business an international organisation is needed to regulate statutory issues. The United Nations established the IMO for the purpose of adopting the highest standards concerning matters of safety, navigation, and pollution prevention. The IMO held its first meeting in 1959 and now comprises 165 flag state members.

The United Nations established the IMO for the purpose of adopting the highest standards concerning matters of safety, navigation, and pollution prevention

The IMO’s purpose is to facilitate the general adoption of the highest practical standards in matters concerning maritime safety, efficiency of navigation and the prevention of marine pollution from ships among governments. Since its inception the IMO has introduced 40 conventions and protocols, although it is the responsibility of member countries to put these regulations into effect.

Statutory Implementation

The process of statutory implementation begins with the development and adoption of regulations by working groups at the IMO. Before these regulations come into force they have to have been accepted by a certain percentage of the IMO’s member states. This can take some time as each country has to introduce these statutory regulations as part of their maritime law before they can actually become mandatory on the ships registered in those countries.

It is important to understand that the IMO can adopt international legislation but that it remains the prerogative of the flag state to implement and enforce it. If a yacht registers with a country that has accepted these regulations then the yacht and her operators have to comply with them.

Maintenance of compliance is verified by a regular survey regime, which is the responsibility of the flag administrations and normally carried out by flag surveyors.

Not all flag administrations have the expertise or manpower to carry out the survey regime themselves, and they often delegate this work to classification societies

This arrangement means that the same class surveyor can issue certification on behalf of a flag state for compliance with, amongst other things, the MCA Large Yacht Code and Load Line Conventions. The class surveyor can also handle issues covered by the various annexes contained within the MARPOL Regulations, such as the prevention of oil, sewage and air pollution.

Class surveyors are often empowered by the state to inspect and certify crew accommodation, safety equipment, safety radio requirements, safety of navigation requirements, international tonnage, Suez and Panama Canal Tonnage Certification, and United States Coast Guard compliance. They are also frequently called on to service the requirements of SOLAS whenever a yacht becomes liable to comply with it.

Clearly, classification and statutory certification often go hand-in-hand where statutory certification requires classification of the yacht, and where a classification society requires valid statutory certification for the class to be valid.

In the preparation of this article the authors gratefully acknowledge the help they received from:

Engel JW de Boer – Service delivery manager, Lloyd’s Register, Rotterdam, The Netherlands

Mario Dogliani – Corporate affairs and communication, RINA, Genoa, Italy

Jean-Jacques Juenet – Commercial manager, Bureau Veritas (BV), Paris, France

Paul Martin – Det Norske Veritas (DNV), Houston, USA

John Guy – Merlin Corporate Communications, London, UK

Nick Gladwell – Regs4yachts, Southampton, UK

Originally published: May 2008.

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Yacht Classifications

  • By Dudley Dawson
  • Updated: July 17, 2009

ytgjul17perf525.jpg

Let’s take a peek into the dark back corner of a London pub a couple hundred years ago, when Britain was the unquestioned ruler of the sea, as a group of Lloyd’s of London insurance underwriters licked their financial wounds from the latest loss of a cargo ship to Davy Jones’s locker. They’d had enough, and proposed to form an independent society to make ships safer by developing standards for construction, operation, and maintenance. Thus was born Lloyd’s Register of Shipping, no longer affiliated with Lloyd’s of London, but still the granddaddy of maritime classification societies.

The concept was so successful in improving safety and cutting losses that spinoffs and imitators soon appeared in other seagoing nations. There are now ten full members and one associate member of the International Association of Classification Societies ( www.iacs.org.uk ). Not all of them class yachts, and of those who do, not all class smaller yachts. The American Bureau of Shipping (ABS), for instance, does not class yachts under 24 meters, or about 79 feet, in overall length.

Each society also has different sets of rules and guides, several of which will be applicable to any given yacht. While national codes, such as the U.S. Coast Guard regulations, and international treaties, such as SOLAS, are mandatory, classification is in most cases voluntary. A shipowner or yachtowner elects to have his vessel classed in order to better assure a certain level of sound design and construction, and consequently, to reduce insurance premiums and losses.

Although there are differences in the details, the societies have much in common. Each issues written rulebooks and guides for use by designers, reviews and approves the vessel plans in advance of construction, and employs dedicated surveyors to assure that the vessel is built in accordance with the plans. There are also periodic inspections by this same corps of surveyors throughout the vessel’s service life to check that it is being maintained to the required standards.

The voluntary nature of classification creates a number of possibilities for a yacht owner. He can pick and choose from the several classification societies that cater to yachts. For instance, an American owner having a fast yacht built in Holland could choose to have it classed by the Norwegian society, DNV (Det Norske Veritas). This is where those detail differences come in, as some designers consider the DNV construction rules for high-speed vessels to be more realistic than those drafted by some other societies. Such shopping for classification is commonplace, and that’s why you’ll find surveyors for each society in each shipbuilding nation. In an Italian yard, for instance, you might find an ABS surveyor working on one vessel and a Lloyd’s inspector working on another, alongside the first. In some cases, where the surveyors are independent, or “non-exclusive” in society parlance, you might find him wearing a DNV jumpsuit one day and ABS coveralls the next.

In addition to choosing his classification society, an owner can choose the level of involvement he wants with classification. Full classification means plan approval before construction, inspection and approval of both construction and installed equipment (anchors, engines, generators, etc.), and periodic inspections and required maintenance after delivery. An owner can also add various options, including most recently, an environmentally based endorsement of the yacht as “green.”

All of this comes at a price, of course, both in meeting the initial requirements and in continuing costs. Some owners view any financial outlay as justified in protecting their vessel and those aboard; others elect to have the yacht designed and built to class, and then drop the class designation when fees and mandated maintenance expenses begin to exceed the savings in insurance premiums.

Finally, an owner can opt to have his designer and builder use the written classification standards as a guide in the construction of his new vessel, without actually contracting with the society. This avoids some of the expenses of questionable value, such as factory testing and equipment certification. Then an independent non-society surveyor or project manager can oversee the construction up to delivery, and the captain, vessel management firm, or favorite boatyard can track maintenance requirements. It’s not official, but it’s still classy.

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Blog | Owner’s Guide to Yacht Classification

Yacht classification is a system used to categorize yachts based on various factors such as size, construction, and intended use. The specific classification categories and requirements can vary between different yacht classification societies, but some common classifications include:

  • Pleasure Yacht: A yacht intended for leisure use, typically not engaged in commerce.
  • Charter Yacht: A yacht that is available for hire for pleasure use, also known as commercial yacht.
  • Large Yacht: A yacht that exceeds a certain size or gross tonnage.
  • Small Commercial Yacht: A yacht that is used for commercial purposes but does not exceed a certain size or gross tonnage.
  • Passenger Yacht: A yacht that is used to carry passengers for hire.
  • Workboat: A yacht or vessel intended for work-related use, such as a survey vessel, cable layer, or other specialty use.
  • Ocean Going: Yachts that are able to make ocean passages and are built and equipped to meet the requirement of such voyages
  • Coastal: Yachts that are intended to operate in coastal and sheltered waters and meeting less stringent requirement than ocean going yachts.

The main differences between yacht classification societies are their specific rules, regulations, and requirements for yacht classification. While many societies have similar overall goals of ensuring that yachts meet certain standards of design, construction, and maintenance, they may have slightly different interpretations of these standards and how they should be applied.

Some societies may have stricter or more detailed rules and regulations than others. For example, one society may have more stringent requirements for fire protection, while another society may place more emphasis on stability calculations.

Another difference is the type of yachts they cover and the services they offer. Some societies focus primarily on pleasure yachts, while others also cover commercial yachts and workboats. Societies may also offer different levels of classification, such as “unrestricted” or “restricted” class, and this might vary depending on the intended use of the yacht.

Lastly, some societies have a more global presence than others, or have more experience or expertise in certain types of yachts or regions. This can be important for yacht owners who plan to take their vessel to different parts of the world and may need to comply with different regulations in different countries.

In short, yacht classification societies are similar in their overall goals, but they can have different rules, regulations, and requirements for yacht classification, different services and different areas of focus. Yacht owners should research and compare different societies to determine which one is the best fit for their specific needs and intended use of the yacht.

There are several yacht classification societies that provide certification and inspection services for yachts and other small vessels. Some of the most well-known include:

  • American Bureau of Shipping (ABS)
  • Bureau Veritas (BV)
  • Germanischer Lloyd (GL)
  • Lloyd’s Register (LR)
  • RINA (Registro Italiano Navale)
  • Det Norske Veritas (DNV) now known as DNV GL

These organizations are responsible for ensuring that yachts and other vessels meet certain standards of design, construction, and maintenance, and they issue certificates of compliance to vessels that meet these standards. They also conduct periodic inspections to ensure that vessels continue to meet these standards over time. Some of them also provide additional services such as collision avoidance, navigation and stability calculations and other specialized services.

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Understanding Yacht Classifications – Definitions, Explanations, and Regulations

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Yacht classifications, also known as classification societies or class societies , are an important part of maritime safety. These classifications dictate the design, construction and ongoing maintenance of large commercial vessels and yachts.

The classifications provide highly detailed and technical standards that cover the yacht’s hull, its engines, and key safety systems.  The application of common safety requirements to personal vessels like yachts is something relatively new, so the procedures are constantly evolving. Typically, it is dependant on the service and the flag of the yacht.

Standard Yacht Types

Before discussing the different types of yacht classifications, it’s important to understand the different yacht types. Yachts are typically segmented based on the overall length and how many passengers they can accommodate. The standard yacht classification types are large yachts or luxury sailing yachts, commercial yachts, and private yachts.

Large Yachts

Large yachts, also known as luxury yachts, is the largest classification type for yachts. A large yacht has a load line length equal to or over 24m or about 80 feet. Just about every flag administrations have adopted safety codes for large yachts. Therefore, this is the only yacht definition having a universal meaning in the international regulatory framework of yachts.

Commercial Yachts

Commercial yachts are ones that are used for commercial use, whether it be sport or charter. These ships do not transport or carry any cargo and carry no more than 12 passengers.

All flag states require that commercial yachts are certified in accordance with a specific large yacht safety code. The most widely used safety code is the MCA Large Commercial Yacht Code (LY2) published in 2004.

Private Yachts

Private yachts are typical pleasure vessels used for the recreational and leisure purpose of its owner and his guests.  In some cases, they are also known as cruising yachts.

What Is A Classification Society?

Classification societies are organizations that set the rules that govern the construction, maintenance, and operation of yachts and vessels. Currently, there are 13 members of the International Association of Classification Societies . Classification societies were first started when insurance underwriters at Lloyd’s of London set standards for the ships that they would ensure.

As a result, Lloyd’s Register of Shipping (LR) was the original classification society. While many of the 13 members do not classify yachts, they cover everything from container ships to supertankers.

The main class societies involved in yachting are the American Bureau of Shipping, Bureau Veritas, Det Norske Veritas, Germanischer Lloyd, Lloyd’s Register, and RINA.

What Is A Flag State?

A vessel’s flag state is the jurisdiction or nationality under whose laws the vessel is registered or licensed. The flag state has the authority and responsibility to create regulations for vessels registered under its flag. These typically involve those relating to the inspection, certification, and issuance of safety and pollution prevention documents for a vessel.

Different flag administrations may perform inspections on the safety aspects of yachts using their own inspectors or use classification societies or other recognized organizations to perform these inspections.

The main flag authorities in the yachting industry are the UK-MCA, Cayman Islands, Isle of Man, Malta, the Marshall Islands, Italy, and Luxembourg.

What Is The Classification Process

The first step of classification involves the assessment of a yacht’s designs and regular inspections during the construction or conversion of a yacht. Once it is confirmed that all standards have been met, a certificate of classification is issued.

The certificate details the standards met, the intended use for the vessel, and whether the vessel should be used only in sheltered waters. The certificate is evidence that a yacht meets industry standards but isn’t necessarily a guarantee of seaworthiness.

Maintaining classification is achieved through regular surveys. These surveys, also known as ‘special’ surveys, typically take place every five years. These surveys assess things like the thickness of the hull, possible fractures, and other potential damage. They also consider the condition of electrical systems, machinery, and equipment.

Mandatory Classification Certificates

There are a variety of different classification certificates. The number and type of the mandatory certificates for a given ship will depend on its size.

International Tonnage Certificate This expresses the internal volumes of the yacht in gross tons. Unlike displacement tonnage, this does not quantify the weight of a vessel.

Large Yacht Code Certificate This certificate covers navigational and signaling equipment, life-saving appliances, fire protection, means of escape, and manning and crew accommodation.

Class Certificate This mainly deals with the yacht’s hull, machinery, electrical equipment, and outfitting.

International Load Line Certificate This certificate covers the weather-tightness of the yacht.

Safety Radio Certificate This certificate only applies if gross tonnage exceeds 300GT. It covers radio communication and distress installations.

MARPOL Annex I Certificate This certificate only applies if gross tonnage exceeds 400GT and covers the disposal of oil and bilge water.

MARPOL Annex IV Certificate This certificate only applies if gross tonnage exceeds 400GT or the yacht is certified to carry more than 15 people and covers the disposal of sewage from ships.

MARPOL Annex V This certificate covers the disposal of rubbish and applies to all ships.

MARPOL Annex VI  This is applicable if gross tonnage exceeds 400GT as well as to all main and auxiliary engines with a power exceeding 130kW. It concerns the emissions from main and auxiliary engines (NOx and SOx).

Safety Construction and Safety Equipment These cover machinery, electrical parts, life-saving and navigational equipment for yachts with a gross tonnage above 500GT.

International Safety Management Certificate This only applies to yachts with a gross tonnage greater than 500GT. A certified management company is requested to carry out this service, preparing operational manuals, procedures for drills, and taking care of the maintenance of the yacht and its installations.

International Ship and Port Security Certificate This only applies to yachts and ships with a gross tonnage greater than 500GT and covers the anti-piracy certification. A certified management company is requested to provide ashore assistance and establish onboard procedures and operational manuals.

Keeping Your Yacht Up To Classification

Tess Electrical has years of experience in maintaining yachts and commercial vessels. We deal with vessels 125’ and above, which have more complex systems dictated by Classification, Flag State and Insurance requirements. Even if vessels are not classed, we can still maintain them to those standards.

Give us a call or send us an email to speak with one of our experienced marine engineers about developing a maintenance strategy for your yacht today.

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How to configure AIS transponder with web interface?

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White Paper on New Class B “SOTDMA” technology

Many people are unaware of the recent approval of a new AIS Class B “SOTDMA” technology that sits nicely between the two existing Class A and Class B technologies.

Clear online information about Class B “SOTDMA” still seems to be in short supply, so we have produced a White Paper on this new “Class B+” technology, highlighting its benefits, how it compares to Class A and Class B and what types of boats and applications should consider installing this new generation of Class B+ transponders.

A full copy of the White Paper can be downloaded by clicking here .

1 – Background

AIS (Automatic Identification System) is now one of the most widely used and significant navigation safety technologies since the introduction of radar. The system was originally developed as a collision avoidance tool to enable commercial vessels to ‘see’ each other more clearly in all conditions and improve the helmsman’s information about his surrounding environment.

Explanation of the new AIS Class B SOTDMA

AIS does this by continuously transmitting a vessels identity, position, speed and course along with other relevant information to all other AIS equipped vessels within range. Combined with a shore station, this system also offers port authorities and maritime safety bodies the ability to manage maritime traffic and reduce the hazards of marine navigation.

Due to the great safety benefits offered by AIS, the fitting of a Class A transponder was made compulsory throughout the world in 2002 for all vessels over 300 gross tonnes or that carried more than 12 passengers. For smaller vessels that fell outside of the mandate, a Class B transponder was defined which allowed fishing and leisure vessels to fit a lower power/cost transponder that worked on the same AIS network and could receive and transmit signals to the Class A transponders fitted to commercial vessels.

AIS transponders are now commonly seen on many leisure vessels and with the approval of personal AIS SARTs for use as Man Overboard systems, in conjunction with Search and Rescue vessels/helicopters now fitting SAR transponders, AIS is becoming an important part of the Global Maritime Distress and Safety System (GMDSS).

Another new AIS application is vessel tracking, with websites like Marine Traffic and AISLive that collect and display thousands of AIS targets from their shore based AIS reception networks, and global satellite reception via companies such as Orbcomm , exactEarth and Spacequest .

Many national marine authorities are installing special Aids to Navigation (AtoN) transponders that can replace traditional Buoys and Beacons and transmit local weather/tidal information to passing vessels, while some large and busy harbours or shipping areas use AIS as part of their Vessel Traffic Services (VTS) to manage and control shipping movements.

It is this continuous expansion of the global AIS network, that has led to the approval of a new Class B technology that sits half way between the original Class B technology and the Class A technology found on commercial shipping. This new technology does not supersede or replace the original Class B transponders, but it does offer significant improvements for some types of vessels and applications. For the purposes of this White Paper, we will refer to this new technology as Class B+.

2 – How AIS Works

To fully appreciate the benefits of this new Class B+ technology, it is necessary to understand how AIS works.

An AIS transponder consists of a GPS receiver and a VHF “Data” Radio. The transponder takes its GPS position and transmits this in Digital Form on two VHF channels dedicated to AIS (161.975MHz and 162.025MHz).

In order that multiple AIS transponders can “play nicely together” and avoid all of the devices transmitting at the same time, causing interference and loss of data, AIS transponders use a system called Time Division Multiple Access (TDMA). This is a similar system to that used in mobile phones, where each AIS transponder claims a very short 26.6 millisecond “time slot” where it transmits its information. The claiming of Class A time slots uses “Self Organised” TDMA where multiple transponders know how to claim and reserve time slots and what to do if there is a dispute with another transponder trying to claim the same time slot.

The system works well and allows up to 4500 ships to work within close proximity of one another, automatically giving priority based on distance apart, i.e. as the number of vessels increases, the ones furthest away do not get a time slot.

When Class B transponders were introduced, they used a slightly different technology called “Carrier Sense” TDMA where the Class B transponder listens to the Class A transponders and as soon as it detects an empty time slot, grabs it and makes its transmission. Occasionally a Class A transponder will “steal” a time slot from a Class B transponder and the system is designed that Class A transponders always take priority over Class B, so the Class B transponder will have to delay its transmission and start listening again for another empty slot.

The number of transmissions that a transponder makes and the type of data it sends varies, based on its Class (A or B), its speed, whether it is manoeuvring and its navigation status. The Class A transponder of a fast-moving ferry may output its position every couple of seconds while a Class B equipped pleasure vessel will only transmit every 30 seconds, whilst underway.

As previously mentioned, the AIS data is transmitted over two channels of the VHF frequency range and a Class A transponder transmits at 12.5 Watts while an original Class B transponder only transmits at 2 Watts which –  to put this in to perspective – is a third of the power of a hand-held VHF that transmits at 6 Watts.

This 2 Watt transmit power restricts Class B transmissions to an absolute maximum range of about 8-10 Nautical Miles and also means that traditional Class B transmissions are often not received by the AIS Satellites that provide global vessel tracking.

3 – The New Class B+ Technology

The new Class B+, often referred to as “Class B SOTDMA” or “Class B 5W”, has been defined to bridge the gap between Class A and Class B transponders, offering some clear advantages for some types of vessels and applications.

Class B+ uses the same SOTDMA technology as Class A and therefore has the same priority when it comes to reserving a time slot, guaranteeing that it will always be able to transmit, even in busy AIS congested waters. For fast moving vessels this is important as a missed transmission can result in a vessel moving a long distance before it next manages to send a transmission.

Another feature that the new Class B+ technology it has taken from Class A, is the increased and automatic changing of transmission rates depending upon speed. Unlike Class A, the update rate is unaffected by whether the vessel is manoeuvring, but as the vessels speed increases, the number of transmissions increases so that other vessels get a clearer and more up to date view of where the boat is.

For slow moving vessels the increased update rates of Class B+ are not so important, but a fast power boat travelling at say 23 knots, will move 360 meters in 30 seconds, which is the update rate of a normal Class B transponder. On a Class B+ vessel travelling at 23 knots or more, the update rate is 5 seconds, so (using the above example) only 60 meters would be moved between updates.

Finally, Class B+ transponders have a higher power transmission 5 Watts instead of 2 Watts and this not only increases the range over which the  vessel’s transmission will be received, assuming good antenna height and performance, but it also significantly improves the AIS Satellite reception, enabling global tracking.

4 – Comparison of AIS Classes

The following tables have been created to provide a “side by side” comparison of the three different classes of AIS.

Class A, B and B+ Functionality

As can be seen from the table above, in normal operation a Class A transponder transmits at a much higher power than a Class B. In “real-life” terms a well installed Class B transponder should be able to transmit up to 7-8NMs whilst a Class A transponder maybe seen as far as 20-25NMs away. With its 5W output, a Class B+ will be better than a Class B (2W), but not x2.5 better, typically 10-12NM should be seen.

As illustrated in the following table, Class B and B+ transmit the same data, a sub-set of the data transmitted by a Class A transponder.

Class A, B and B+ Transmitted Data

Finally, the table below shows the different data transmit rates of the three systems. As can be seen, Class A transponders have several different transmit rates, based on speed, manoeuvring and Nav Status, whereas the Class B+ transmission rate is purely based on speed.

Comparing Class B+ to the original Class B, it can be seen that the simple two update rate (underway or stationary) of the original Class B has been expanded and increased in Class B+. For any boat that regularly travels at over 15 knots and particularly for boats capable of travelling at over 23 knots, the increased transmission rates offered by Class B+ are an important benefit.

Class A, B and B+ Transmit Rates

5 – useful links.

If this White Paper has encouraged you to learn more about AIS or even purchase an AIS system for your boat, then the links below should be of interest…

  • Digital Yacht’s website where you can find the latest information on our AIS products.
  • All About AIS website for more information on AIS systems
  • Wikipedia article on AIS
  • IMO website that details the global carriage requirements of AIS
  • US Coast Guards website on AIS
  • Maritime Traffic website leading online AIS website

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B+ is an interesting development in AIS for small craft but raises a few questions: 1/ Are these transmissions backward compatible with older AIS receivers eg: they do not show up small craft as large ships , 2/ If a large ship filters out class B does that include B+, 3/ If there is a lot of class A traffic, does the B+ traffic have a lower priority, ie: the faster update rate is a target and not necessarily guaranteed, 4/ Assuming enough processing power is available, could some existing class B transceivers be software upgraded ( not the power output ) to support class B+ or is the requirement that B+ must be at 5W, 5/ with 4dB more power and more frequent transmissions B+ transceivers are presumably more power hungry, how much extra is this in practical terms ?

Hi Dean, Some really good questions which I will try and answer: 1) All Class B+ transmissions are backward compatible and will be received by all Class A, traditional Class B and AIS receivers. Also Class B+ equipped vessels will not appear as large ships just because they use the same SOTDMA technology – Class B+ uses the same boat categories as Class B i.e. Pleasure Craft, Sailing Craft, Fishing, etc. 2) Class B and Class B+ are seen as being the same type of AIS transmission and although they will always be received by the Class A transponders on large vessels, in theory they could be “filtered out” or not displayed on a large vessel ECDIS (chart plotter). 3) Class B+ has the same priority as Class A and will take priority over a traditional Class B in busy shipping areas. 4) As far as I am aware no Class B units can be software upgraded to Class B+ but Digital Yacht will soon be announcing a cost effective upgrade path to Class B+ for their existing Class B transponder owners. 5) In reality, due to the very short transmissions (26mS) Class B and Class B+ transponders have pretty much the same power consumption (around 0.25A at 12v)

Will the Digital AIT 5000 (B+) display AIS targets & information on my Garmin 7200 chart displays?

Yes the good news is that our latest AIT5000 and AIT25000 Class B+ transponders will work with all AIS compatible chart plotters either via NMEA0183 or NMEA2000, depending upon what interface(s) the chart plotter has. There is no change in the way a Class B+ transponder interfaces to other equipment, it is just the underlying AIS transmission technology that has changed.

Best regards PAUL

Shouldn’t the chart showing the difference in “Class A, B and B+ Transmitted Data” indicate Class A vessels transmit “ETA + Destination + Draught NO NO” be corrected to show YES NO.

Well spotted, glad to see someone has accurately read our White Paper and you are 100% right.

I have corrected and updated the White Paper to V1.01.

Thank you for your feedback.

The AIT5000 kit includes a external GPS Antenna. 1. Is this GPS antenna required when boat already has a external GPS antenna connected to chart plotter via NMEA2000 ? Regards John

I am afraid that all Class B(+) AIS Transponders must have their own GPS receiver and antenna. This was stipulated in the International Class B AIS Transponder specification, to ensure that all transponders can work autonomously, with no reliance on other equipment that may fail or be turned off.

The latest AIT5000 has a very sensitive GNSS receiver and many dealers mount the antenna below deck on GRP hulled boats. As long as it is mounted vertically with just fibre-glass above it, you should get good performance and can use the GNSS Status page of proAIS2 to check reception before bolting everything down in their final resting place.

I’m a sailor and tipicaly the boatspeed in good windconditions is 6 -7 knt. In that case I don’t see a difference between class B and B+. Is this correct? The article is focused on the advantage of class B+ for fast traveling leisure boats, but I wonder what about the visibility of low speed vessels. Is it a risk that fast moving vessels don’t see slow moving vessels in time due to the fact that the signal of a class B transponder has a lower priority than class A and B+? If that is true is the installation of a class B+ transponder on slow moving vessels an advantage for the visibility on fast moving vessels?

Best regards, Johan Snijders

For a slower moving yacht, you are correct, there is less benefit in having a Class B+ compared to the original Class B, but the extra power 5W versus 2W should give you better transmit range (typically an additional 2-3 NMs) and the SOTDMA technology will ensure that you are always getting a transmission slot even when surrounded by hundreds of AIS equipped vessels.

A slow moving yacht with Class B+ is transmitting at the same rate as a normal Class B and I think there would have to be an awful lot of AIS equipped vessels in the area and transmission slots in very limited supply, before the normal Class B became noticeably less visible to fast moving vessels.

That said, the number of AIS transponder equipped vessels is only going to increase and it might be worth investing in Class B+ to be sure that you get the best future performance.

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AIS B+ explained: How to see and be seen on the water

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A new generation of AIS B+ transponders claims to make leisure boats more visible. We explain how

Automatic Identification Systems (AIS) may have originally been conceived as a collision avoidance system for commercial shipping but in recent years they have become a popular safety aid for leisure boats as well.

Not only does AIS allow you to see and be seen, even when out of sight due to darkness, fog, land or range, but it is also becoming a useful navigation tool now that transponders are being fitted to beacons, buoys and other aids to navigation. AIS SARTs (Search And Rescue Transponders) have also been approved for use as man overboard devices, which can be picked up by SAR helicopters as well as AIS-equipped surface craft.

Until recently, however, AIS has operated a distinct two-tier system: Class A transponders, which are mandatory on all vessels over 300GT or carrying more than 12 passengers, and Class B transponders that allow smaller fishing and leisure vessels to fit a lower power, lower cost transponder.

The trouble is that leisure boats equipped with AIS B transponders may not be quite as visible as you think, especially in busy areas with multiple AIS targets. Now a change in the rules and a new generation of AIS B+ transponders has helped level the playing field, so what are the changes and how do they affect potential buyers?

How AIS works

To help explain the changes you first need to understand how AIS works. An AIS transponder consists of a GPS receiver and a VHF data radio. The transponder transmits this GPS position in digital form on two VHF channels dedicated to AIS (161.975MHz and 162.025MHz).

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In order to avoid multiple devices transmitting at the same time, AIS transponders use a system called Time Division Multiple Access (TDMA). Each transponder communicates with others in the area to avoid clashes and claim its own short 26.6 millisecond time slot. The system allows up to 4,500 craft to operate in the same vicinity, automatically giving priority to those that are closest and therefore likely to be at greater risk of collision.

ais-explained-AIS-transmitting.jpp_274722762_491406861

All AIS equipped boats are constantly communicating with each other using short bursts of VHF transmissions

However, the way different classes of transponder get their time slot varies. Class A transponders use a system called Self Organised Time Division Multiple Access (SOTDMA), which enables them to negotiate with other Class A transponders to reserve a time slot and book future ones. Class B transponders use a different technology called Carrier Sense Time Division Multiple Access (CSTDMA).

This allows Class B transponders to listen in to Class A transponders and grab an empty time slot to make their transmission. The system is designed so that Class A transponders always take priority over Class B ones, meaning that a Class A transponder will occasionally steal a time slot from a Class B one and force it to delay its transmission until another empty slot appears.

The number of transmissions that a transponder makes varies according to several different parameters, including Class (A or B), speed, navigation status and whether it is manoeuvring. The Class A transponder of a fast-moving ferry may output its position every couple of seconds while a Class B-equipped pleasure vessel will only transmit every 30 seconds.

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A Class A transponder also transmits at 12.5W while a Class B transponder only transmits at 2W – a third of the power of a 6W handheld VHF. This restricts Class B transmissions to a maximum range of 8-10 nautical miles and means that traditional Class B transmissions are often not received by the AIS satellites that provide global vessel tracking.

AIS B+ explained

The new Class B+, otherwise known as Class B SOTDMA or Class B 5W, bridges the gap between Class A and Class B transponders, offering clear advantages for some types of vessels and applications.

Class B+ uses the same SOTDMA technology as Class A and therefore has the same priority when it comes to reserving a time slot, guaranteeing that it will always be able to transmit, even in busy AIS congested waters.

It also increases the transmission rate in line with your speed (but is unaffected by other manoeuvres), giving other vessels a clearer and more up to date view of where you are.

ais-explained-Princess in fog_274768012_491406861

While an AIS transponder is no replacement for a radar, it can help you be seen by commercial traffic

For displacement motor boats the more frequent updates may not make a big difference, but a planing power boat travelling at 23 knots will move 360 metres in the 30 seconds it takes one of the older Class B transponders to transmit its next signal (or 0.5nm at 30 knots). On a boat equipped with a Class B+ transponder travelling at 23 knots or more, the update rate is 5 seconds, so would only travel 60 metres between updates.

Finally, Class B+ transponders have a higher power transmission of 5W instead of 2W, which not only increases the range over which it will be received by other boats (assuming there is good antenna height and performance) but also significantly improves the ability of AIS satellite receivers to track your position.

Which type should I fit?

The answer depends on the type of boat you have, the sort of cruising you do and the budget you’re prepared to spend. The cheapest solution is to fit an AIS receiver or download one of the many apps that use shore-based reception networks.

This is fine for showing AIS traffic in your vicinity and allowing you to communicate with them using their MMSI number, but it doesn’t make your boat visible to other AIS users.

Class A transponders are at the opposite end of the scale but cost around £2,000, have an integral AIS display and could be considered overkill on a smaller boat that is predominantly used for coastal cruising .

ais-explained-Ship in fog Poole_274768022_491406861

At night or in fog it can be very hard to see what’s going on around you, especially if it’s shielded behind a headland or another larger craft

It’s also something of a myth that big ships have the option to ‘switch off’ Class B transmissions in busy areas. There is no filter option on commercial or leisure AIS receivers, so provided it picks up a Class B transmission, it will trigger collisions risk alarms just like a Class A one. Only when overlayed onto a big ship’s ECDIS screen can the ship’s master choose to filter out the visual clutter of Class B targets (but not the transmission itself).

For smaller craft a Class B ‘black box’ transponder costing around £500 and linked to a multi-function display should be fine. However, the limited range and frequency of transmissions could prove a drawback, particularly on faster craft or those venturing further afield where the higher transmission power will significantly improve the ability of AIS satellites to track your position once out of range of surface-based VHF. In these circumstances spending the extra £150-£200 for a Class B+ transponder makes good sense.

None of them should be seen as a replacement or alternative to a radar because they don’t pick up land, squalls or other boats and obstacles that don’t have a transponder fitted.

Digital Yacht, Raymarine , Simrad, Garmin and Ocean Signal all offer Class B+ transponders for around the £700 mark. If you’re looking to fit AIS for the first time or to upgrade an existing Class B set, a Class B+ transponder looks like the logical next step.

Thanks to Digital Yacht for their assistance with compiling this article.

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Comparing Class B AIS Transceivers

Icom vs. vesper: which ais-b transponder is best for cruisers.

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The popularity of Automatic Identification Systems (AIS) has grown exponentially in recent years, particularly among small- to mid-sized cruising sailboats. Lower costs have played a big hand in this, as has increased participation (the more boats with AIS, the more boats there are to see); however, the primary driver remains boat owners looking to increase safety.

Comparing Class B AIS Transceivers

Photo by Frank Lanier

AIS transceivers help skippers navigate high-traffic areas by painting an overview of marine traffic and providing important information about nearby commercial ships and other vessels that are AIS-equipped. AIS is a seemingly simple system that transmits dynamic information about a vessels speed, course, and position plus static information including the vessels name, call sign, and Mobile Maritime Service Identity (MMSI) number over marine VHF frequencies.

AIS transceivers are split into Class A (commercial) and Class B (recreational), and they broadcast information from every 2 to 30 seconds. Class A transceivers have a maximum VHF power output of 12.5 watts, are required to broadcast more data than Class B units, and must update data more frequently than Class B. Class B transceivers are designed to provide a similar yet limited service, at a lower cost, to smaller vessels not required to carry a Class A unit. Class B units transmit less data at a slower rate using a 2-watt transmitter. AIS listen-only devices, like the Raymarine AIS250 and SI-TEX/Nasa Marine receiver we tested (March 2007), receive AIS broadcasts but do not transmit any information.

Class B transceivers relay vessel information, position data, course over ground, speed over ground, heading, status, and even offer a means of direct dialing another boat via VHF channels by utilizing a provided MMSI number and select VHF channels. For specifics on the AIS broadcast data types and frequencies, check out this article on www.practical-sailor.com.

While not a replacement for radar, AIS benefits from the propagation characteristics of VHF, allowing it to see around and behind objects such as large ships, small islands, rocks, etc.-assuming whatever is behind these objects is equipped with AIS.

AIS transceivers can be useful search-and-rescue tools. Like an activated EPIRB, they offer the Coast Guard and other rescue personnel the boats exact location and amplifying information. They also can be used to track the latest generation of AIS-based man-overboard beacons like those we reviewed in the May 2013 issue.

Our last look at AIS units was in September 2009, when we evaluated the Navico NAIS-300 and the West Marine AIS1000. Both were Class B devices capable of sending and receiving AIS data. Each relied on compatible chartplotters, multi-function displays, or PCs to display their information. The NAIS-300 received a Recommended rating, while the AIS1000 was named Budget Buy.

In our August 2010 issue, contributor Joe Minick reported the pros and cons of using an AIS receiver with a PC display as a collision tool while cruising near Turkeys Dardanelles Strait. Fast-forward three years (a lifetime in the world of electronics), and standalone AIS units with integral displays have come into their own, at comparable prices to the non-display units we tested previously.

What We Tested Our latest evaluation compared Class B transceivers from two key players in the AIS market. From Icom, a global company whose product line includes communications equipment and products based in the marine, avionics, land mobile, and wide-band receiver industries, we tested the MA-500TR. New Zealand-based Vesper Marine, a relatively new company that has steadily garnered a worldwide reputation for quality and innovation, submitted its WatchMate 850 for testing.

Comparing Class B AIS Transceivers

Photo courtesy of Icom

Both transponders will pick up signals from AIS-equipped search-and-rescue transponders (SARTs) or man-overboard (MOB) beacons, but how they display the signals may differ. The WatchMate 850 clearly explains that these distress signals are displayed with a special icon and an alarm will sound, but Icom does not address it in the MA-500TRs owners manual. We were unable to test this or to get confirmation from Icom, but its likely the SART icons appear like other AIS targets.

AIS transponders use GPS signals to get position data and VHF signals to send and receive other data. Of our test products, only the WatchMate 850 features an internal GPS antenna. The 500TR must be networked with a chartplotter to get position data. Neither of the tested AIS transponders comes standard with a VHF antenna, so users have two choices: Buy and install a dedicated VHF antenna for the AIS device or use a splitter to connect the transceiver to an existing VHF-radio antenna. Depending on the hardware, this latter option could potentially affect signal strength. Vesper Marine offers a specialized AIS/VHF splitter, the SP160, which the company claims has no signal-strength loss. (We recently tested the SP160 and will be reporting on it in an upcoming article.) Other companies like West Marine and Digital Yacht also market splitters designed for AIS connections, but we have not yet tested them.

For advice on where to mount an AIS-VHF antenna, click here .

How We Tested The Icom and Vesper Marine units went head-to-head in bench tests and field tests while cruising the waters of Hampton Roads, Va., an AIS-target hotspot with a steady stream of recreational, commercial, and military vessels.

The products were rated on AIS functions, control capabilities, user-interface, filtering capability, display quality, and screen visibility, both belowdecks and in bright sunlight. Other rating considerations included power consumption, networking ability, water resistance, ease of use, and installation requirements; price and warranty also were factored in final ratings.

Unlike VHF radios, transmitting on the AIS devices is automatic, low-wattage, and too fast for testers to effectively measure power output or consumption while transmitting, so we relied on manufacturer-provided measurements for these specs. (See Value Guide.)

Icom 500TR The MA-500TR (681) is a Class B AIS transponder designed for non-SOLAS vessels (non-commercial pleasure craft, work boats, and small vessels, etc). The 500TR receives dual AIS channels (87B and 88B) simultaneously and receives both Class A and Class B AIS information. Vessel information (boat MMSI, name, type, position, speed, course, etc.) is automatically transmitted at fixed intervals or under base station control.

The 500TR features a full dot-matrix display with adjustable backlight and contrast. It looks similar to a mini-radar display with north-up and course-up options, as well as display ranges from 0.125 nautical miles to 24 nautical miles.

Comparing Class B AIS Transceivers

Photos by Frank Lanier and courtesy of Vesper Marine

The front of the 500TR has 11 pushbuttons that control various functions. These include a dedicated MOB button, an essential feature on chartplotters and handy feature on AIS units. Pressing the 500TRs MOB button drops a waypoint flag icon that you can steer back to. The power button serves double duty, also providing easy adjustment of display brilliance and contrast. All of the controls and their respective functions were fairly intuitive and straightforward.

Operationally, the 500TR has a number of collision-risk management functions, such as a list of local targets, as well as a danger list of targets you could potentially collide with. The Target list shows all detected AIS-equipped vessels and targets sorted by distance, from closest to farthest; this is updated every 5 seconds.

The Danger list shows all vessels within 6 nautical miles CPA (closest point of approach) and 60 minutes TCPA (time to CPA) from your vessel. These parameters are not user-adjustable; however, they can be sorted by CPA or TCPA. The CPA is user adjustable between 0.1 and 6 nautical miles, in 0.1 nautical miles increments, while the TCPA can be adjusted from 1 to 60 minutes, in 1-minute increments. Additionally, the Detail screen shows all available information about the selected AIS target (name, MMSI, etc).

As a target vessel enters the CPA / TCPA range, its displayed icon blinks and an alert beep is sounded; an external speaker can be added to make the collision alarm easier to hear when away from the unit.

The 500TRs compact size and waterproof rating (IPX7, or submersible to 3 feet for 30 minutes) mean it can be mounted at the helm, in the cockpit, or belowdecks at the nav station. Testers found the 500TR display easy to read belowdecks, in direct sunlight, and while wearing polarized sunglasses. Backlighting and contrast adjustments were easy to use and effective.

When connected to a compatible Icom VHF radio, the 500TR provides an easy means of making individual DSC calls to another boat without having to manually input MMSI numbers. Simply select a vessel using the cursor keys, then push the 500TRs DSC button.

Other 500TR features include the ability to store up to 100 waypoints in memory and to receive, display, and store DSC safety-related messages from Class A AIS transponders (up to 20 automatically stored in memory).

The back of the unit contains connectors for a GPS receiver, VHF antenna, power connections, and an NMEA plug. The 500TRs data output uses the NMEA 0183 format for easy connectivity to most current radars, chartplotters, and navigation systems. Theres also a cloning cable receptacle that allows users to connect the unit to a computer, conceivably creating a repeater display.

For troubleshooting and operational checks, the 500TR has a diagnostics page that allows you to check both monitor operation and transponder health.

Another useful feature is that the transmit function can be turned off, essentially converting the 500TR to a receive-only unit. This is done by pressing down the left and right arrow keys simultaneously until a transmit off message appears on the screen; to resume transmitting, simply reverse the process; we did not find directions for doing this in the owners manual.

The 500TR comes with an external GPS antenna, a NMEA connector cable, mounting bracket kit, and DC power cable.

Bottom line: The 500TR has a lot to offer, including a three-year warranty, but when compared to the WatchMate 850, its limited target-filtering ability and its external GPS antenna requirement held it back. But, its almost $100 less than its competitor (and costs less than some current display-less Class B transceivers), so it gets the Budget Buy pick.

Vesper Marine WatchMate 850 A driving philosophy behind the WatchMate 850 is the ability to reduce screen clutter by focusing on important targets. Target filtering is based on a user-selected combination of target speed, range, CPA, and TCPA, enabling users to reduce screen clutter by filtering targets that are moored, stationary, or moving away. Alarm and filter settings are grouped into profiles (harbor, coastal, offshore, etc.) and can be activated with a single selection. This allows you to pre-set set the various parameters to suit your preferences, then toggle between the groups as desired.

Targets are organized by collision-risk priority, with higher-risk targets at the top of the list, and can be stepped through in order of preference, as can the complete list of targets.

With great filtering options comes great responsibility to ensure targets of interest are not inadvertently filtered out by setting values too high (speed, for example) or too low (say, for range). Testers liked that the total number of targets tracked is always displayed, regardless of how aggressively you have them filtered. They also liked that when viewing a targets details, a press of the CPA button displays a plot showing the targets relative position to your vessel, at the time of their closest point of approach. This allows users to see whether a crossing target will pass ahead or astern. While the 500TR displays the CPA of a selected target, the WatchMate 850 actually advises you on whether to turn port or starboard to avoid a potential collision.

Unlike the Icom, the WatchMate 850 features an internal GPS receiver and GPS patch antenna, which greatly simplifies installations with a clear view of the sky; an optional externally mounted GPS antenna can be purchased for belowdeck installations. Testers marveled at the compact size of the WatchMate external GPS antenna, especially compared to the 500TRs GPS antenna.

Another useful tool is the anchor watch feature. Using heading information, the WatchMate 850 determines the location of the bow when dropping the hook, providing greater accuracy than just using the position of the GPS antenna (which is typically located at the stern). Theres also a screen that lets you fine-tune the physical location of the GPS antenna, providing even greater accuracy.

The WatchMate 850 can broadcast and receive safety and emergency messages to and from all AIS-equipped vessels within VHF range. It can also be placed in silent mode, which keeps the AIS and GPS receivers operating normally but switches off the automatic transmission of your vessels position and details, rendering the device a listen-only unit.

Like the 500TR, the 850 can initiate direct DSC calls to a target when connected to a compatible VHF radio without the need to manually enter MMSI numbers. Its USB connection also means it can easily be connected to onboard computers, providing both GPS and AIS data to any PC charting application.

Comparing Class B AIS Transceivers

Testers liked the AIS Status screen, which provides a host of information that can be used to verify proper operation or while troubleshooting. Additionally, the WatchMate 850 continuously monitors its transceiver performance, and if a problem is detected, an error alert pops up on the display and an audible alarm sounds.

The WatchMate 850 does not have a dedicated MOB or waypoint-entry button; in fact, there is no mention of any waypoint or MOB entry features in the owners manual. Its a feature we liked on the 500TR, and one that would be a good addition to the WatchMate, in our opinion.

The 850 is advertised as being compatible with all AIS search and rescue / MOB devices. If an AIS-SART or AIS-MOB is triggered, the WatchMate 850 sounds an alarm, displays a special icon, and provides continuous position updates as well as bearing and range to the SART or MOB. It can also be configured to activate an external alarm, buzzer, or other indicator.

The WatchMate has four control buttons and a power button. The control buttons grant access to a soft-key user interface designed to provide faster access to functions with fewer button pushes than a traditional menu-driven interface.

The fear with any piece of gear combining numerous functions with few control buttons is that operation beyond the basics may not be particularly intuitive. Testers were pleasantly surprised at how easy it was navigate the WatchMates menus without reaching for the manual, even when drilling down to the more advanced functions.

The rear of the WatchMate 850 has plugs for connection to an external GPS, VHF antenna, NMEA input/output connections, and a waterproof USB connector-the latter two allow you to integrate the AIS data into chartplotters or computer-based tracking systems respectively.

The WatchMate 850 features an easily viewable, grayscale, LCD display with adjustable backlighting and contrast, and a display range from 0.25 nautical miles to 48 nautical miles. Its screen is significantly larger than the 500TR. Even though some screen area is taken up by the soft keys (displayed along the right side), theres still a lot of dedicated display area remaining for a unit of this size. Testers found the display easy to read in al lighting conditions.

The WatchMate 850 is rated IPX7 like the 500TR, so it too is a good candidate for below- or above-deck installations. The package includes a protective cover, bracket and flush mount hardware, USB data cable, and a CD with the owners manual and other assorted data.

Bottom line: The WatchMate 850 provides a wealth of user-adjustable settings and customizable options with regards to AIS filtering and display. The ability to prioritize targets based on CPA, TCPA, bearing, range, etc., is a definite plus in the war on screen clutter. Its our Best Choice for an AIS-B unit with an integral display.

Conclusion Both the 500TR and the WatchMate 850 performed as advertised and will allow users to detect, track, and (hopefully) avoid other AIS-transmitting vessels. Screen clutter can quickly become an issue when navigating a busy harbor, however, and the WatchMate 850 had the upper hand in resolving this challenge.

Vespers WatchMate 850 simply brings a lot more to the table in terms of features, options, and display customization than the 500TR. Its numerous targeting options allow users to reduce target overload and see the forest in spite of all the trees, so to speak. Testers also like that it has an internal GPS and like the 500TR, it can easily be patched into existing VHF antennas.

The Icom 500TR is a solid, well-built unit that works well and is intuitive. Extensive filtering options will not be as much of a priority for sailors who don’t frequent crowded harbors-or may not be worth the extra $100-and for those boat owners, the 500TR, our Budget Buy pick is worth considering.

Regardless of the unit that best suits your needs, AIS is arguably the most important collision-avoidance tool to hit the maritime world since the advent of radar. It doesn’t give you X-ray vision, but it can sure seem that way when monitoring AIS-equipped vessels located behind headlands, larger targets, and other traditional radar-blind spots.

The keywords here of course are vessels equipped with AIS. Despite AISs growing popularity, there are still a large number of vessels out there with neither the mandate nor desire to have AIS onboard, including a high percentage of the worlds small craft and military vessels.

Prudent seamanship practices (such as maintaining a proper watch) and radar should be your first line of defense against collisions. AIS is a powerful anti-collision tool, but it should be only one of multiple instruments in your navigational toolbox, one that is used with full knowledge of its limitations.

Comparing Class B AIS Transceivers

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The last time you’ve looked at AIS units was 2009 what kind of crap is that you need to update this right away this is completely ridiculous so, after all these years, you haven’t done a second review.14 years Between reviews is shameful. I’m not going to renew my subscription.

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AIT1500 – AIS Transponder with built-in GPS & NMEA 0183

$ 749.95

“Entry level AIS Transponder with industry standard NMEA0183 interface and internal GPS antenna that makes installation aboard smaller fibreglass (GRP) boats much quicker and easier.”

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KEY FEATURES

The AIT1500 is an ultra-compact Class B Transponder with two outputs; NMEA 0183 and USB, allowing it to work with the majority of existing and legacy AIS compatible chart plotters or computer software packages on the market today. Featuring a remote silence button option, two NMEA 0183 Inputs and Outputs, integral USB cable, four status LEDs and a new rugged ABS plastic enclosure, the AIT1500 is the perfect small boat AIS transponder.

Configuration of your vessel’s fixed data, such as MMSI, call sign, boat name, dimensions etc. is made easy with the included Windows and Mac compatible proAIS2 software*. Once configured, the unit will provide AIS data to a PC or Mac running suitable navigation software or a dedicated chart plotter, such as the latest Garmin, Raymarine, Navico, Standard Horizon and Furuno units.

As well as transmitting your own vessel’s position so that other AIS equipped vessels know where you are, the AIT1500, when connected to an existing VHF antenna (via a splitter) or dedicated AIS antenna, will receive all AIS targets within range of your boat – typically up to 30NM.

For optimum AIS performance on sailing yachts, we recommend our SPL1500 Splitter featuring “Zero Loss” technology which allows you to use your boat’s existing VHF antenna at the top of the mast for maximum range.

* Except US where dealer programming required

NOTE – AIS target range, like VHF range is dependent upon a number of installation factors such as; antenna gain, antenna height and size of ground plane. Ranges in excess of 20 miles should be possible if all of these factors are perfect.

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SPECIFICATIONS

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  • Class B AIS Transponder with built-in GPS & NMEA 0183
  • Shares the same latest generation AIS technology as our AIT2000 and AIT3000 units
  • Internal GPS antenna for easy installation on fibreglass (GRP) hulled boats
  • Built-in high performance 50 channel GPS receiver (ideal also as a backup GPS)
  • USB Interface for simple plug and play connection to a PC or Mac
  • High speed NMEA output (38,400 baud) – compatible with industry standard plotters
  • Low Speed NMEA output (4,800 baud) – for providing GPS data to DSC VHF radio
  • Low Speed NMEA Input (4,800 baud) – for multiplexing additional NMEA0183 data
  • Requires VHF antenna or dedicated AIS antenna (available as optional accessory) or splitter (SPL1500)
  • Remote Silence Switch option
  • Supplied with programming software for user programming*
  • Easy to install black box solution

ProAIS2 V1.20 Mac OSX Zip

Proais2 v1.20 windows zip, ait1500 quick start v1 01 eng pdf.

An AIS which sends and receives data is known as a transceiver (or often called a transponder). There are also simple devices called AIS receivers which pick up transmissions and decode for displaying on a compatible chart plotter or PC based navigation system – or even an iPad or tablet.

AIS transponders will allow you to receive data from vessels close to you, but will also allow you to continuously transmit your vessel’s identity, position, speed and heading, as well as other relevant information, to all other AIS-equipped vessels within your range.

To transmit its position, an AIS transponder must have its own GPS antenna. All our AIS transponders are supplied with a GPS antenna or have a built-in GPS antenna.

To help you choose the right AIS transponder for you, here are a few keys that may help you out:

  • Receive targets on a plotter – if you want to receive only AIS targets on a plotter then you have the choice between the AIT1500, AIT1500N2K, AIT2000 and AIT2500. The AIT1500 or AIT1500N2K have a GPS built into the transponder and is therefore recommended for fibreglass boats up to 30 feet. The AIT1500 only has an NMEA 0183 interface while the AIT1500N2K has a NMEA 2000 interface. The AIT2000 (class B) and AIT2500 (class B+) both have an external GPS antenna and can therefore be installed on any type of boat. They both also have an NMEA 0183, NMEA 2000 and USB interface.
  • Receive AIS targets on software or applications – If you only want to receive AIS targets on navigation software or applications, then we recommend the iAISTX. This is an AIS transponder with an external GPS antenna and a built-in WiFi server.
  • Receive AIS targets on a plotter AND software/applications – To receive AIS targets on a plotter and software/applications at the same time, we recommend the AIT5000 (Class B+). The AIT5000 is the most complete AIS transponder with a certified zero loss VHF antenna splitter, NMEA multiplexer, external GPS antenna and WiFi server.
  • AIS for rental boats – if you are looking for an AIS receiver or transponder that you can put in your suitcase and want to use when renting a boat then the Nomad is the right AIS transponder for the job. It is the only portable AIS transponder that has a built-in GPS, is USB powered and comes with a portable VHF antenna.

Now that you have an idea of which AIS transponder you need, you will also need to choose between Class B or Class B+ AIS transponder.

There are 3 types of AIS transponders: Class A, Class B and Class B+ :

  • Class B AIS Transponder is for recreational craft installation and is a simplified, lower powered 2W transceiver which is normally a black box and uses a connected chart plotter to display local AIS targets. It transmits every 30 seconds regardless of vessel speed and can’t transmit additional data like destination port.
  • Class B+ AIS Transponder (also called Class B SOTDMA or Class B 5W ) is a new standard that utilises SOTDMA format transmissions which offer a 5W power output (2.5 x more powerful than a regular Class B), a guaranteed time slot for transmission in busy traffic areas and faster update rates depending upon the speed of the vessel. It’s ideal for ocean sailors requiring the best possible performance and future proof satellite tracking applications, fast power boats and smaller non-mandated commercial vessels.
  • Class A AIS Transponder must have a dedicated (and type approved) display to show the location of nearby AIS targets and transmits at 12.5W. Data is sent at up to every 2 seconds depending upon the vessel speed and the display also allows for data to be inputted to the transmission such as vessel destination. A Class A device is normally used on commercial vessels as its Type Approved to IMO specifications.

If the AIS transponder doesn’t have a built-in VHF splitter (i.e. AIT5000), there are 2 options: either install a dedicated VHF antenna for AIS or install an antenna splitter so that the main VHF antenna is used for both VHF radio and AIS.

For those who want to use their existing VHF antenna, then we recommend the use of a certified zero loss VHF antenna splitter such as our SPL1500 and SPL2000. Please do not use a non-zero loss certified VHF antenna splitter. They are inexpensive, but they can destroy your AIS transponder.

For those who want to install a VHF antenna dedicated to AIS, then we recommend a VHF antenna tuned to AIS frequencies. The AIS transmission and reception works on 2 dedicated channels which use the frequencies 161.975 and 162.025 MHz (channel 87B and 88B). VHF frequencies in the maritime environment use frequencies from 156.0 to 162.025 MHz and most VHF antennas are designed to provide maximum gain on channel 16 (156.8 MHz). You can now find antennas on the market dedicated to AIS frequencies such as the HA156 antenna.

These antennas, dedicated to AIS frequencies, offer maximum gain at 162 MHz (which is the centre between the 2 AIS frequencies 161.975 and 162.025 MHz). So if you install a VHF antenna instead of a VHF antenna splitter for your AIS receiver or transponder, then choose an AIS frequency VHF antenna to compensate for the loss due to the installation of the antenna lower down than the main VHF antenna at the top of the mast. The graph below shows how a dedicated AIS frequency antenna (162 MHz) provides a better VSWR and therefore a better transmission and reception.

The AIS transponder can be configured with the free PC/Mac software called ProAIS2. The ProAIS2 software can be downloaded free of charge directly from our website. The functionality of the proAIS2 software is the same on Windows or Mac.

Installation of the proAIS2 software, also installs the USB drivers and we recommend not plugging the transponders USB cable in to the PC/Mac until after you have installed proAIS2. Once the installation is complete, plug the USB cable in to the computer to complete the USB driver installation. The transponder receives enough power from the USB connection to power the processor and ancillory circuitry required to configure the transponder, however the GPS will not get a fix, the NMEA interfaces will not be working and the transponder will not transmit while on USB power.

Digital Yacht are not the only company that supply proAIS2 with transponders, but to our knowledge, we are the only company to produce a video showing how to configure and diagnose Class B transponders with it. So we hope that not only Digital Yacht users but owners of other brands will benefit from this video.

Please note that the MMSI number cannot be changed once the product has been configured. To change the MMSI number, you must reset the product and for that, please contact us.

To find out how to use the proAIS2 software to configure an AIS transponder, please watch the video below: https://www.youtube.com/watch?v=FTiMynP8KDs

If you want to stop transmitting your position, you can either fit a physical silent switch on the AIS transponder or you can stop the AIS transmission through the ProAIS2 software.

You can stop the AIS transmission of our iAISTX & AIT5000 with their built-in web interface. Easy to stop the AIS transmission with your smartphone.

This is a very valid question. Especially if you have spent a few hours installing the transponder then knowing that it is working OK is very important. Using the proAIS2 configuration software allows you to see if the GPS position is OK. You can monitor the AIS reception of other vessels. As well as ensure that there are no errors or alarms. However, if you are new to AIS, there is always that nagging doubt as to whether other vessels are seeing you.

The best test of a Class B transponder is to ask someone else in your marina, who has AIS, to check that they are receiving you on their system. If your vessel is stationary, then a transponder will only transmit every 3 minutes. This increases to every 30 seconds when your speed over the ground (SOG) is greater than 2 knots. Therefore, do allow some time for them to detect you. Also when they first receive your transmission, the only data they will see is your position, speed, course and MMSI number. It can take up to 6 minutes to receive your “Static Data” (boat name, call sign, vessel type, dimensions, etc.). This is normal and is the way the AIS system regulates the amount of data being transmitted.

The other increasingly common method of testing an AIS transponder is to look on one of the online “live” AIS websites and the most popular of the free services is MarineTraffic.com

However, it is important for you to be aware of the limitations of these online sites. As a result, do not assume that you will always be picked up by them. Each of the different online services are only as good as their network of AIS receiving stations. In many cases enthusiasts/volunteers operate these. In some areas the coverage is great but there are definitely “holes” in coverage.

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Cruising the Moskva River: A short guide to boat trips in Russia’s capital

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There’s hardly a better way to absorb Moscow’s atmosphere than on a ship sailing up and down the Moskva River. While complicated ticketing, loud music and chilling winds might dampen the anticipated fun, this checklist will help you to enjoy the scenic views and not fall into common tourist traps.

How to find the right boat?

There are plenty of boats and selecting the right one might be challenging. The size of the boat should be your main criteria.

Plenty of small boats cruise the Moskva River, and the most vivid one is this yellow Lay’s-branded boat. Everyone who has ever visited Moscow probably has seen it.

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This option might leave a passenger disembarking partially deaf as the merciless Russian pop music blasts onboard. A free spirit, however, will find partying on such a vessel to be an unforgettable and authentic experience that’s almost a metaphor for life in modern Russia: too loud, and sometimes too welcoming. Tickets start at $13 (800 rubles) per person.

Bigger boats offer smoother sailing and tend to attract foreign visitors because of their distinct Soviet aura. Indeed, many of the older vessels must have seen better days. They are still afloat, however, and getting aboard is a unique ‘cultural’ experience. Sometimes the crew might offer lunch or dinner to passengers, but this option must be purchased with the ticket. Here is one such  option  offering dinner for $24 (1,490 rubles).

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If you want to travel in style, consider Flotilla Radisson. These large, modern vessels are quite posh, with a cozy restaurant and an attentive crew at your service. Even though the selection of wines and food is modest, these vessels are still much better than other boats.

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Surprisingly, the luxurious boats are priced rather modestly, and a single ticket goes for $17-$32 (1,100-2,000 rubles); also expect a reasonable restaurant bill on top.

How to buy tickets?

Women holding photos of ships promise huge discounts to “the young and beautiful,” and give personal invitations for river tours. They sound and look nice, but there’s a small catch: their ticket prices are usually more than those purchased online.

“We bought tickets from street hawkers for 900 rubles each, only to later discover that the other passengers bought their tickets twice as cheap!”  wrote  (in Russian) a disappointed Rostislav on a travel company website.

Nevertheless, buying from street hawkers has one considerable advantage: they personally escort you to the vessel so that you don’t waste time looking for the boat on your own.

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Prices start at $13 (800 rubles) for one ride, and for an additional $6.5 (400 rubles) you can purchase an unlimited number of tours on the same boat on any given day.

Flotilla Radisson has official ticket offices at Gorky Park and Hotel Ukraine, but they’re often sold out.

Buying online is an option that might save some cash. Websites such as  this   offer considerable discounts for tickets sold online. On a busy Friday night an online purchase might be the only chance to get a ticket on a Flotilla Radisson boat.

This  website  (in Russian) offers multiple options for short river cruises in and around the city center, including offbeat options such as ‘disco cruises’ and ‘children cruises.’ This other  website  sells tickets online, but doesn’t have an English version. The interface is intuitive, however.

Buying tickets online has its bad points, however. The most common is confusing which pier you should go to and missing your river tour.

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“I once bought tickets online to save with the discount that the website offered,” said Igor Shvarkin from Moscow. “The pier was initially marked as ‘Park Kultury,’ but when I arrived it wasn’t easy to find my boat because there were too many there. My guests had to walk a considerable distance before I finally found the vessel that accepted my tickets purchased online,” said the man.

There are two main boarding piers in the city center:  Hotel Ukraine  and  Park Kultury . Always take note of your particular berth when buying tickets online.

Where to sit onboard?

Even on a warm day, the headwind might be chilly for passengers on deck. Make sure you have warm clothes, or that the crew has blankets ready upon request.

The glass-encased hold makes the tour much more comfortable, but not at the expense of having an enjoyable experience.

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Getting off the boat requires preparation as well. Ideally, you should be able to disembark on any pier along the way. In reality, passengers never know where the boat’s captain will make the next stop. Street hawkers often tell passengers in advance where they’ll be able to disembark. If you buy tickets online then you’ll have to research it yourself.

There’s a chance that the captain won’t make any stops at all and will take you back to where the tour began, which is the case with Flotilla Radisson. The safest option is to automatically expect that you’ll return to the pier where you started.

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Flotilla Radisson Royal

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Most Recent: Reviews ordered by most recent publish date in descending order.

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Flotilla Radisson Royal - All You Need to Know BEFORE You Go (2024)

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