The International One Metre (IOM) is a class of Radio Sailing Boat used for racing under the ISAF Racing Rules of Sailing.
It is a measurement-controlled box rule originally created by the ISAF-RSD (now the IRSA) in 1988 in an attempt to harmonise the various one metre rules created around the world. The IOM Class Rules specify a standardised sail plan and control of the other major performance dimensions (displacement, length, and draught) while allowing some freedom in hull, fin, and bulb design.
The IOM is now the largest and arguably most competitive of all radio sailing classes.
The International One Metre Class Association was formed in 2003 as an owners association to support the class and promote racing. This function was originally carried out by the IRSA (previously known as the ISAF-RSD). The continuing association with IRSA entitles the class to hold World Championships officially recognised by the International Sailing Federation.
For more about the design development of the IOM over the years you might enjoy reading the Graham Bantock’s long running series of articles that include illustrations from Lester Gilbert. A world champion radio sailor, Graham has made significant contributions to model yachting and the IOM class as a designer, sailmaker, and supplier of components to the world from his UK company that are distributed globally. His articles provide a class history of performance at the major international regattas with a decidedly technical comparison analysis. They were published in Seahorse Magazine and Acquaint, a UK Model Yachting publication:
Some observations on the list of Worlds podium finishers below: