The next important decision is which style of radio controlled boat hull to pick out. If you’re planning a scale project, your option will obviously be determined by the full-size boat you would like to model. But sport, racing and sailing boat hull types present very special personality. In general, there are two hull classifications: monoplane and hydroplane.
MONOPLANES Monoplane hulls have one continuous surface in contact with the water. Monoplane hulls can be divided into two subcategories: deep-V’s and shallow-V’s.
Deep-V’s. Nearly all monoplane hulls are deep-V’s. This typical layout brings the keel to a sharp point well beneath the surface of the water. The bottom of the boat is angled upward steeply toward the hull’s sides, resulting in a radio controlled boat that knifes through the water with a relatively large wetted surface area. This style of hull is stable at every speeds and provides sharper steering response. The downside is that the extra hull surface that contacts the water causes drag that limits top speed. Still, as well as the correct power system and accurate tuning, these radio controlled boats are quite fast particularly for the beginner.
Shallow-V’s are the faster of the two monoplane types since they run with less surface area in contact with the water. The shallower keel v’s-angle produces a flatter bottom that causes less friction. The downside is that a reduced amount of contact with the water means a reduced amount of stability, so they are more difficult to control and require more precise trimming. Shallow-vees are very popular for entry-level racing, this type of radio controlled boat or the so-called Cracker boxes being the most common.
HYDROPLANES Hydroplanes maintain more than one surface in contact with the water. They involve tunnel hulls, catamarans, outriggers and stepped hydro’s.
Tunnel hulls are most often associated with full-size racing boats. They get their name from the raised center section of the hull. 2 outer sections or sponsons sit in the water with a tunnel between them. As the boat gains speed, air builds up in this tunnel and raises the boat higher out of the water. This reduces the surface area that contacts the water. This means less drag and higher speeds, while the relatively wide spacing of the sponsons maintains stability. This design provides a excellent balance of speed and handling for beginners.
Catamarans (cats) work on the similar principle as tunnel hulls and differ only in shape . They have more steeply angled sponsons much like deep-vee monos with a tunnel along the center. A cat’s tunnel tends to be taller and narrower than a tunnel hull’s, so it takes longer to preserve stability. These also, are a good beginner design.
Outriggers are at the highest of the performance ladder; their sponsons and main hull are separate pieces. This improves the airflow at high speeds, so outriggers are the fastest radio controlled boats; a number of even run at more than 90 mph! The obstacle is that they are designed to work best at full throttle. At slow speeds, they sit too low in the water and do not handle well. Also, they are the least forgiving when it comes to setting the trim.
Stepped hydroplane hulls contain notches perpendicular to the center line that partition the wetted surface into 2 or more sections. These notches pick up the radio controlled boat up on step sooner, and that improves performance. At speed, these notches decrease the wetted area, reducing drag. This hull type includes a varied group, from straightforward deep-vees with little steps in the hull, to 3-point hydro racers such as the full-size Miss Budweiser turbine-powered, unlimited hydroplane. At full speed, three-point hydro’s travel on 2 tiny areas of the forward sponsons and the centrally located propeller at the rear.
Any way you look at it radio controlled boats are a super way to spend a sunny afternoon. Take the time to enjoy the activity and spend time with your family and friends.