Special spark plugs ignite Idaho business

Published 9:00 pm Sunday, September 28, 2003

SPOKANE — SmartPlugs Inc. delivered five 500-watt generators to the U.S. Army last week. That tiny delivery could ignite the Sandpoint, Idaho, company’s future.

Mark Cherry says he is confident the generators can do the two things the military wants of its hand-carried units in the future: one, the ability to burn jet fuel, and two, do so with exhaust too cool and quiet to be detected at 400 yards.

The secret is a spark plug that does not spark.

Cherry invented the Smart Plug, which can replace conventional spark plugs in almost any internal combustion engine. It’s already been tested successfully in 100 aircraft, recreational and automotive engines.

The plug acts something like a miniature diesel. Screwed into a cylinder head where a spark plug would normally go, the Smart Plug is actually a small cylinder with a catalytic stem in the center.

The tip of the heated stem ignites fuel vapors, which send jets of flame into the engine’s main combustion chamber. Those flames touch off fuel in the engine’s main combustion chambers far more effectively than a spark plug does.

Engines run more efficiently and cleanly using almost any kind of fuel. A van at the University of Idaho is running on Aqauhol — 70 percent ethanol and 30 percent water.

Even more remarkably, the Smart Plug works even if the engine loses electric power. The heat created in the combustion process keeps the catalyst hot enough to sustain the ignition process.

That virtue has opened up the first commercial market for the Smart Plug: experimental airplanes. Kits are available for two types of engines that command about 40 percent of that market. The plugs astound airshow attendees who see engines run without magnetos, a frequent source of engine failure.

The market for the plugs could be much broader, but for now, SmartPlugs will focus on aviation and a few other vertical markets, and finish the "proof of concept" trials for the Army.

Success could result in orders for 1,000 generators per year for several years. Cherry says a consultant for the British army has also inquired about the generators.

Cherry has always been confident of his technology, but recognizes the tremendous inertia of industries that have relied on the spark plug for 140 years. The Smart Plug will have to touch off more than jet fuel.

"It’s like turning a supertanker," he says. "We’re building the team to make it succeed."