A radio-controlled boat is a boat or ship model controlled remotely with radio control equipment. Type Fun sport Electric sport boats are the most common type of boat amongst casual hobbyists. Hobby-quality boat speed generally start at around 20 mph and go up from there, and can be just as fast or faster than their internal-combustion counterparts, with the latest in lithium polymer and brushless motor technology. Ready-to-run speedboats from AquaCraft, ProBoat and OffshoreElectrics can reach speeds over 40 mph out of the box and with modifications can reach well into the 50-60 mph range. These types of boats are referred to as "hobby grade" and can be found only at hobby shops and retailers. "Toy grade" boats which are obtained through mass consumer retailers, are generally much slower and their maximum speeds are usually less than 15 mph. Scale Scale boats are replicas of full-size boats. They are to scale of the full sized ones. They can be small enough to fit into your hand, or large, trailer-transported models weighing hundreds of pounds. More often than not they are a miniaturized version of a prototype, built using plans and/or photos, although there are variants that utilize freelance designs. An offshoot of this style of marine RC's is radio-controlled submarines. Sailboats Sailboats use the power of the wind acting on sails to propel the boat. Model sailboats are typically controlled via a multi-channel radio transmitter in the hands of the operator with a corresponding receiver in the boat. By changing the position of the two joysticks on the transmitter signals are sent over two separate channels on a single radio frequency (assigned to the individual boat/operator). On the boat, the radio receiver is connected to two battery-powered electric motors or servos. Signals from the radio transmitter are interpreted by the radio receiver and translated into instructions to change the position of the servos. One servo controls the position of both main and jib sails together (allowing the sails to be trimmed), the other the position of the rudder (allowing the boat to be steered). Racing sailboats The racing of radio-controlled yacht racing is governed by the same International Sailing Federation - Racing Rules of Sailing that are used for full-sized crewed sailing boats (with the inclusion of Appendix E, that introduces special rules to govern the radio-controlled sport). Vane controlled boats sail under their own rules. There are four international