By Bob Woodward
It wasn’t that long ago that confusion reigned in whitewater kayak design. While every kayak designer seemed to have a similar goal in mind, each took a different design path to get there. Now there’s more similarity within each category of whitewater kayak design, the different categories being traditional (old school), play/rodeo (new school), hybrid (old/new school combinations), and steep-creek boats.
Kayaks based on a traditional design will generally be eight and a half to nine feet and longer in length. They’ll feature rounded (displacement) hulls. This was the accepted hull shape for decades and is still the shape of slalom boats used in the Olympics.
A displacement hull is rounded along its bottom and more rounded along its sides (chines). This hull shape is fast through the water and ideal for carving turns, surfing, and ferrying. The hull’s initial stability may be a bit tippy, but once moving in whitewater, the boat becomes more stable.
Put a slight amount of rocker (bow-to-stern upsweep) into a displacement hull, top it with a rounded deck, and you have a good river-running/big-water boat. Match that same hull shape with a relatively flat deck fore and aft, and you have a river-running boat that also offers some play characteristics.
New-school play/rodeo boats are generally around seven feet in length but can be as short as five feet nine inches. Play/rodeo boats feature flat planing hulls and squared-off steep sides (hard chines). The hull’s flatness makes for superb surfing and fast spinning. The harder chines allow the boat to move more freely through the water for trick moves. Combine hard chines with a flat hull and you get a more stable boat when doing cartwheels, aerial blunts, and other stunts.
Play/rodeo boats have depressions or channels cut into their hulls at the bow or stern or along the edge where the chines meet the hull. These help break surface tension between the water and the hull, making a boat looser for initiating tricks.
The latest play/rodeo boat hulls are turned dramatically up at the bow and stern. This allows the boat to spin more quickly. Flattened ends also help the boat slice through the water, particularly on vertical moves. Play/rodeo boats have excellent initial stability as well as reliable secondary stability when put on edge.
Combining design elements from the old and new schools are the hybrids. These boats are longer, like traditional ones, but with modified hulls that are slightly rounded, with just a touch of flatness, and have harder-than-traditional chines. Hybrids are designed for beginner use and to serve as transition boats for longtime paddlers interested in progressing slowly from a displacement-hull boat to a new flat-hulled play/rodeo design.
A more direct offshoot of traditional designs is the steep-creek boat. A steep-creeker is easy to recognize by its bulbous shape (higher volume) with pronounced bow-to-stern rocker. Rocker makes the boat turn and react faster. The boat’s added volume makes it ride high in turbulent waters and resurface following submersion after running a big drop. Some steep-creek boats have rounded displacement hulls, while others have flat or modified flat hulls.
One characteristic that all modern whitewater boats share, regardless of design, is a larger cockpit. Once cockpits were small, and hard to get into and out of. Today, they are both longer and wider, for easy access and egress.
Another shared characteristic of most contemporary kayaks is roominess. Despite the constricting appearance of many designs, paddlers have plenty of room for legs and feet. This was accomplished primarily by raising the cockpit section so paddlers can sit with their legs in a more ergonomic bent-knee position rather than stretched out flat.
Being able to adjust thigh braces and backband while seated in the boat is also an improvement shared by most high-end whitewater kayaks.