F5-M, or Marblehead (town in USA), has been a very popular class since a number of years. It is a constrction class, meaning everything not explicitely forbidden is allowed. This has lead over the years to yachts which have an enormous sailing potential and can sail very fast in different wind conditions. From next to low wind to up to stormy conditions, M-boats can handle nearly everything. With increasing wind speeds the sails get smaller and smaller in order to allow for save boat handling at the water. But as the wind increases, so does the fun sailing those boats.

The general dimensions of a Marblehead are: hull length of 1,27 m, the sail size is limited to a specific maximum area and is calculated by plugging the rig dimensions into a formula.

As a speciality, F5-M boats do not only come with the classical way of rigging, but also something known as “Swing Rig” has become popular. This special type of rigging is known for its ease of handling, which may be important, when you have to change sails because of changed wind conditions in less then 3 Minutes.