journal k ayaker’s
CAN YOU HEAR ME NOW? PHOTO: RYAN CREARY
KAYAK Q&A BY CONOR MIHELL
BOOST YOUR RANGE ANDCHOOSE THE HULL THAT’S RIGHT FOR YOU
How can I boost the range of my VHF marine radio?
Handheld VHF marine radios work on a line of sight principle, with the transmission range being a function of the unit’s wattage. For ex- ample, a five-watt radio has a transmission range of about five nautical miles. Radio repeater stations placed in elevated areas along coastal re- gions greatly increase the range of transmission—this is why compact marine radios (and even basic weather radios) can pick up weather forecast broadcasts almost everywhere sea kayakers like to paddle. But dead zones do exist. Sea kayak instructor and
Paddlinghq.com
founder David Johnston had problems receiving forecasts and making a call to the coast guard to file a float plan on Lake Superior’s remote Michipicoten Island. “It’s minerals in the rocks that kill reception,” says Johnston. “We had to get offshore about half a kilometer to pick up the coast guard.” Similarly, hazy or cloudy weather can also reduce reception. Since radio waves are deflected and obstructed by landforms, going
offshore is the best way to boost range. Climbing to an elevated point can also work—the idea is to open up your VHF’s sight lines. John- ston points out a basic principle that can also improve transmission: hold the radio as vertical as possible to keep its antenna high. Length of antenna also dictates a radio’s range. If you’re headed far off the beaten path, consider purchasing a longer aftermarket antenna that’s compatible with your radio.
30 ADVENTURE KAYAK | SUMMER/FALL 2013
What are the pros and cons of hard-, soft- and multi-chine hull designs?
First, some terminology: chine refers to the area where the sidewall of the kayak meets the bottom of the kayak; a soft-chine boat exhibits gentle curves while a hard- or multi-chine boat has abrupt edges. The early skin kayaks of the Arctic relied on wooden ribs and longitudinal stringers for form—the latter being responsible for the single hard- chine, V-shaped hull of the Inuit or Greenland-style kayak and the multiple hard chines of the Aleutian baidarka design. It wasn’t until the advent of fiberglass and plastic that builders could design rounded and shallow-arch hulls without pronounced edges. According to Pygmy Kayaks’ John Lockwood, hard chines enable a
sea kayak to carve crisper turns. When the paddler shifts her weight to tilt the boat, the sharp angles of a hard- or multi-chine hull effec- tively become a curved keel. Think of what happens when you engage the edge of a parabolic ski or snowboard—it’s essentially the same phenomenon when a tilted kayak moves through the water. Lock- wood says that the turning motion is enhanced in a single hard-chine hull; these designs will also turn with less angle of tilt. Lockwood’s calculations demonstrate that a multi-chine hull has 3.2
percent less wetted surface (and therefore less water resistance) than a hard-chine hull, and so is about 3.2 percent more efficient. The difference between multi-chine and soft-chine hulls is even subtler. Ultimately, it comes down to personal preference, says Current Designs Kayaks found- er Brian Henry, “The difference is not drastic.” Still, he point out, “You’ll never find a performance surf ski or Olympic kayak with any hard chines.”
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