The next considerable determination is which type of radio controlled boat hull to choose. If your are planning a scale project, your selection will apparently be determined by the full-size vessel you want to model. But sport, racing and sailing boat hull types present very unusual personality. In general, there are two hull classifications: monoplane and hydroplane.
MONOPLANES Monoplane hulls contain one uninterrupted surface in contact with the water. Monoplane hulls can be separated into two subcategories: deep-V’s and shallow-V’s.
Deep-V’s. Largely monoplane hulls are deep-V’s. This conventional layout brings the keel to a sharp point well beneath the surface of the water. The underside of the boat is sloping 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 right power system and proper tweaking, these radio controlled boats are quite fast specially for newbees.
Shallow-V’s are the faster of the two monoplane types since they operate with a lesser amount of surface area in contact with the water. The shallower keel vee-angle produces a flatter bottom that causes less drag. The downside is that less contact with the water means a reduced amount of stability, so they are more difficult to control and require more accurate trimming. Shallow-vees are very widespread for entry-level racing, this type of radio controlled boat or the so-called Crackerboxes being the most common.
HYDROPLANES Hydroplanes have more than one surface in contact with the water. They include tunnel hulls, catamarans, outriggers and stepped hydros.
Tunnelhulls are most often related with full-size racing boats. They get their designation from the raised center portion of the hull. Two outer sections or sponsons sit in the water with a tunnel between them. As the boat gains momentum, 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 newbees.
Catamarans (cats) operate on the similar principle as tunnelhulls and fluctuate only in shape . They have more steeply angled sponsons much like deep-v’s monos with a tunnel along the center. A cat’s tunnel tends to be taller and narrower than a tunnelhull’s, so it takes longer to preserve stability. These also, are a good beginner design.
Outriggers are at the pinnacle 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; some even run at more than 90 mph! The problem is that they are intended to work best at full throttle. At slow speeds, they sit too low in the water and do not handle well. In addition, they are the least forgiving when it comes to setting the trim.
Stepped hydroplane hulls have notches perpendicular to the centerline that part the wetted surface into two or more sections. These notches get the radio controlled boat up on step sooner, and that improves performance. At speed, these notches reduce the wetted area, reducing drag. This hull type includes a diverse group, from straightforward deep-vees with little steps in the hull, to three-point hydro racers such as the full-size Miss Budweiser turbine-powered, unlimited hydroplane. At full speed, three-point hydros travel on 2 small areas of the forward sponsons and the centrally located propeller at the rear.
Any way you look at it radio controlled boats are a terrific way to spend a sunny afternoon. Take the time to enjoy the activity and spend time with your children and friends.
