Introduction

Monohulls:  These hulls have a bottom surface which offers a single continuous wet surface when running, The hull is one piece and  shaped like a "V" when viewed bow/stern.  Their large inner space eases the installation of driveline and motor components.  Monohulls can be further divided into 3 primary categories.

• Deep-Vee:  These handle rough water amazingly well by using its hull shape to carve through waves rather than trying to ride over them.  They have an angle (Vee) between a horizontal plane and the hull that varies from 16º to 28º.
• Shallow V Hulls have angles that are not higher than 16º.  Because of this design they are faster than Deep Vees due to less surface area in the water.  The downside is they can be more tricky to adjust and run and do not handle the rough water as well.
• Crackerbox hulls  have a flat to 3 degree V hull.  By design the crackerbox tends to side-slip on turns and requires a bit of skill to drive well.  These must be run on smooth water.

Hydroplane: The term hydroplane in the most general sense simply defines a hull that runs on more than one wetted surface. In other words, a hydro is anything that isn't a mono.  These boats have been designed to trap a cushion of air beneath the hull to lift them and thus reduce the amount of boat in contact with the water. Hydroplanes can be further divided into 4 primary categories.

• Unlimited 3-point Hydro:  These are a comprised of a hull with two sponsons at the front and normally running on the prop at the rear end, thus the name 3 point hydro.  The two sponsons are joined by an elevated section that traps air and lifts the hull. They are fast boats and very critical to adjust and drive.
• Catamaran: The catamaran hull consists of two hulls called sponsons joined by an elevated superstructure containing the drive and control components . The elevated superstructure creates a tunnel and the wind passing through the tunnel creates a lifting effect on the hull reducing drag and increasing performance. Catamaran hulls are typically fast and easier to drive than other hydro hull types.
• Tunnel Hulls:  Tunnel hulls are a small catamaran type hull using an outboard motor. Due to the weight of the motor at the rear of the hull tunnel hulls are less stable than a catamaran. The tunnel hull flies on the cushion of air in the tunnel and is more difficult to trim and drive than the catamaran and are very vulnerable to a blow over.
• Outrigger:  The only type of R/C boat not based on a full size boat, the outrigger or rigger is the fastest type of hull.  Electric powered models have exceeded 120 MPH. The rigger consists of two small sponsons attached with metal or composite "booms" to a rectangular center section containing the drive and control assembly. They may or may not have sponsons at the rear.

Stepped Hulls

Hull steps are transverse breaks in the bottom plane, straight or fan shaped. They create a clean break in the planing surface for reduced skin friction. Like a transom, a step ends a planing surface and the theory is that it causes the water to miss contact with forward portion of the following plane. Substantial reduction in wetted surface under relatively smooth water conditions can thus be achieved. There must be a clean break of the water as it leaves the step; with air behind it. If not the step will create drag and even suction.