Sanctioned in 1998. The International One Metre is the fastest growing class in the world. The rules in this class are identical to those used throughout the globe. The class has a one-design rig and weight minimums, but the hull design is very much developmental. One meter long, with a sail area as large as a Marblehead. 39.37" long (One meter)

The versatile International One Metre (IOM) is one of the most popular class in the radio sailing world, and many USA sailors enjoy regular travel for competition. Others prefer local sailing, and local fleets are the class backbone. USA's annual Nationals began in 1998. The class formed in the late 1980s, specifying three (3) one-design rigs with the hull/foils controlled by box rule. This format encourages evolution and created our highly refined fleet of today, where creative skippers continue to test new ideas. We race in the lightest breeze up to very strong winds and waves, where we need our smallest rig up to 35-40 knots. The hull weight limit allows amateur designers/builders to carefully create competitive IOMs and test their mettle against the best commercially available. Besides our plethora of purchase options, we have a recent global boom in home-built woody hulls now too. While the most skilled skippers usually win the regatta, no single design dominates our World Championships on even years.

The Marblehead (or simply "M") is a 50 inch long yacht providing exciting performance and the ability to handle most sailing conditions if rigged properly. This development class is restricted in overall length and sail area. It has spawned two sub-classes, the "American Marblehead" and the "Classic Marblehead". The Marblehead is considered the leader in the use of advanced construction materials and techniques. 50" long, 800 sq. inches sail area.

The M or Marblehead Class, sometimes called the "50/800", is a high-performance development class designed by Roy L. Clough of Marblehead, MA in the 1930's as the largest model that would conveniently fit in a standard American car of the time.

It has grown into an International Class, with competitive fleets worldwide.

M's are considered the largest "high tech" R/C model class with active designers/builders and steadily growing numbers of participants. Think of them as the "Formula One" of radio- controlled race boats.

It is a development class (unless specifically prohibited, "anything goes") with the main restrictions being a hull length of 50 inches and a sail area of 800 square inches. The class has matured over the years to produce a high-performance model that can be sailed in a wide range of conditions by changing rigs.

The hull and rigs tend to use advanced materials and techniques. Boats are available from several suppliers who can provide them from basic kit form to fully assembled. There is also an active used boat market at the local level. Many older designs can be made locally competitive with simple updates. The M Class has a large ownership base, with over 3000 registered hulls in the US with that many or more worldwide. It is sailed in most areas of the country. Competition is available from local club to international level.

To get started, first register your boat with the Class Secretary.

Once you have registered your boat, a "measurement certificate" will be required if you want to compete in organized regattas. To obtain this certificate, an official Class Measurer will perform a detailed examination and measurement of the hull, appendages, sails, and rigs and if all are found to comply with class rules, a certificate will be issued.

Registering an M Class

1. Become an AMYA member and obtain your AMYA membership number. No registration number will be issued without an AMYA membership number.

2. Complete the AMYA Yacht Registration form contained in Model Yachting. Include your e- mail address on the form. Make out a check for $10 to Bruce Andersen and mail it with the Yacht Registration form to him. Do not make out the check to AMYA - registration funds are used for Marblehead Class expenses and are not part of the AMYA.

3. If you are transferring ownership include the existing registration number and previous owner's name.

4. You will be issued a new sail number if this is a new registration, or a card with the old sail number in your name if this is a transfer of ownership of a previously registered boat. A new number may be issued if the provenance of the hull is unknown.

One Design Sanctioned in 1995. Also called "One Design One Meter". The ODOM is based on a U.S. One Meter design. This small-sized yacht's kit must be initially purchased from the manufacturer. Sails are strictly controlled, but may be purchased or made from scratch. This one design class allows no variations. The class is managed by a class association. 39.37" long.

Odom is a One Design Class. See the Class Rules for specifications. Length 39 3/8". Weight 7 1/4 lbs. height bottom of bulb to masthead 75". Comes in 12 hull colors. Minimum construction time. Good entry level boat. Handles strong puffs, choppy water, and points well.

One Design Sanctioned in 1997. Large one-design modeled after full-size "Maxi" boats. 2000 sq. in. of sail, 30 pounds displacement and is 79" long.

Performance is the name of the game and these boats will get up on plane in a breeze, particularly on a reach. Many top sailors will attest, including Nationally ranked IOM skippers; this is as close to "real boat" sailing as you will find in a R/C model boat.

The boat is 79" in overall length, 63" at the waterline with a 15" beam and carrying 2,000 square inches of sail on a fractional rig. The minimum weight of the boat is 30 pounds, although most boats in the fleet are closer to 32 pounds (up to 35 lbs). The keel bulb weighs in at 19 pounds.

As a one-design class; the hull form, rudder and rig/sail dimensions are controlled by rule. That said there are opportunities for significant innovations in electronics and sail control; two channel boats are competitive as are boats operating with up to 7 channels. Additional features include powered boom vangs (introduced by Adrian Olson), powered backstay tension and jib trim in order to provide improved on the water sail control, similar to a "real boat". Multiple rigs are not required and the boat moves well across the wind ranges to 20+ knots.

There have been 80+ boats built to date, primarily by George Ribeiro and Adrian Olson. George Ribeiro is the current builder of record. He offers build kits to various stages of completion. George's coordinates are (831) 247-1428, george.sail@icloud.com and 360 Fiesta Way, Watsonville, CA 95076.