PORT TREVORTON -- Standing at the edge of the runway, Ron London guides his model helicopter through the air. Like a jazz guitarist, he improvises on the spot, guiding the chopper into a variety of flips, spins and barrel rolls.

His friend, Bill Allenbaugh, stands a few feet back, admiring the show.

"Oh man," says Allenbaugh, a less-experienced model helicopter flier. "The outside blade (on the helicopter) spins at the speed of sound. So if they hit you, they'll kill you. Chop you in half. It's not a kid's toy."

He makes it look easy, but according to London, flying a model helicopter requires a steady hand and mind.

"I've been flying (model) planes for 23 years, these for two," he said, gesturing at the gas-powered helicopter sitting on the ground. "(Helicopters) are much more difficult."

If you flub the controls on a plane, it'll continue to glide for a while before you lose control, he said, but "with a helicopter, you let go of the sticks, you've got to guide this all the way. It's non-stop work to fly a helicopter."

Popping open the cockpit, London pointed to the chopper's four internal computers, each of them controlling a different part of the helicopter.

But that's where the fun of flying a helicopter comes from, he said, "the challenge."

London and Allenbaugh drove down from Dubois Sunday morning to take part in the Susquehanna Valley Modelers model airplane fly-in at the club field off Winding Road.

Club president David Bailey said the group has been holding fly-ins going on 30 years now. About a dozen people turned out for Sunday's fly-in, but Bailey said membership has been down as of late.

"This year it's slacked off quite a bit," he said. "I don't know if it's the economy or what ... It's easier to get into model flying now than it ever was."

While he was flying, the linkage on the wing of one of Bailey's planes came loose and he momentarily lost control. Fortunately, he was able to pull it out of a spin and land it safely.

"I usually don't crash," he said as he crouched over the plane later, tightening the linkage. "So (my collection) grows over the years. I have around 10."

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