In a grassy field at the north end of Boulder Municipal Airport, I find Alfonso Ossorio sitting atop a picnic table, watching with childlike wonder as motorless glider planes land on the runway. Dressed in an Army green expedition shirt and khakis, Ossorio has a sturdy build and a thick shock of graying hair. The 55-year-old doesn’t look like an atmospheric scientist or an aerospace engineer or any of the other science and technology professionals who tend to gravitate toward sailplaning for its brainy aspects. And he isn’t one. He tells me that before he fell in love with planes without engines—sometimes called sailplanes, sometimes called gliders—he used to fly commercial jets and helicopters for a Fortune 100 company. “Piloting a glider is the toughest flying challenge I’ve ever had,” Ossorio says. “The others are run by gas. You keep a glider up in the air by using your smarts to read the sky; it’s like playing chess with Mother Nature.”

After we watch a pilot-in-training touch down in front of us, Ossorio introduces me to the glider—a glossy white carbon-fiber and fiberglass ship with a 66-foot wingspan—I’ll be flying in today. During 17 years of living along the Front Range, I’d often admired the sleek vessels that silently soar over the Flatirons. But it wasn’t until feeling the pressure to do something epic for my 40th birthday that I booked a flight.

The snug, dual-control cockpit where Ossorio and I will sit, one behind the other, looks claustrophobically small. It’s so tiny, in fact, that there’s no room for a real door; instead, the roof of the plane pops open like a hatch. “Climb in like you’re getting into the bathtub,” Ossorio says. I lower myself in and squirm to fit my legs around the instrument panel. Ossorio shuts the clear plexiglass canopy and settles into the seat behind me. For a moment, I feel like Maverick in Top Gun. That is, until I remember I’ve willingly traded twin engines capable of propelling a plane to Mach 2 for a motorless aircraft and an emergency parachute backpack.

Get Your Glide On

Three sailplaning clubs are located within a 75-minute drive of Denver.

Soaring Society of Boulder launches gliders every weekend in the spring, summer, and fall at Boulder Municipal Airport. The public is welcome. While SSB is a members-only club and doesn’t provide commercial flights, Mile High Gliding—which operates out of the same airport—offers introductory rides starting at $99.

Black Forest Soaring Society, located at Kelly Airpark in Elbert, provides glider rides starting at $95 for 15 minutes. The flights offer a bird’s-eye view of the U.S. Air Force Academy and the Front Range.

Colorado Soaring Association owns Owl Canyon Gliderport about 20 miles north of Fort Collins. In the summer, you’ll find this group flying every weekend. Besides offering rides to the public ($95 for about 30 minutes), CSA also offers classes for newcomers interested in learning to fly.

Aeronautical engineers have been experimenting with gliders since the late 1800s, but it wasn’t until shortly thereafter that people began using them for sport. Not surprisingly, Germany became the world leader in sailplaning because of the ban prohibiting the country from constructing, or even flying, military power planes after World War I. (Civilian power planes were limited as well.) Soaring gained traction in the United States in 1930 when pilot Frank Hawks flew a glider cross-country from San Diego to New York. The Soaring Society of America, the umbrella organization for the sport here, held its first meeting in 1932.

But it wasn’t until 27 years later, in 1959, that seven pilots living along Colorado’s Front Range formed the Soaring Society of Boulder (SSB). A nonprofit, volunteer organization dedicated to furthering the pastime, the SSB—and other clubs like it in the area—takes advantage of a phenomenon most residents of the Denver metro area never even notice: thermals, or rising currents of air.

In fact, the Front Range is known as a mecca of sorts for glider pilots because unlike in many other places, soaring is a year-round pursuit here. Typically, June, July, and August are peak gliding months because thermals primarily exist in the summertime, when warmer ground air rises up to meet cooler air above, creating lift, the force that opposes the weight of the plane and holds it aloft. But along the Front Range, we experience two additional types of lift—ridge and wave—that can develop at any time of year thanks to our unique mountains-meet-the-plains topography. Ridge lift occurs here when the wind blows from the east and strikes the foothills, deflecting air upward. Wave lift is a natural oscillation caused by wind flowing over a mountaintop. “Riding waves gets pretty wild,” Ossorio says, explaining that waves, which generate 3,000 vertical feet of lift per minute (about twice as much as even the most powerful thermal), are the strongest form of energy gliders use. “I refer to wave flying as surfing the Banzai Pipeline,” he says. “It’s a lot of energy, so you better know what you’re doing.”

Over the years, I’d been told that gliders provide the closest approximation to flying like an eagle or a red-tailed hawk, both of which I hope to spot today while riding the air currents above Boulder. Glider pilots keep their planes in the sky by balancing the natural forces of lift, gravity, drag, and thrust, just like birds do with their bodies. In addition to standard aviation instruments such as compasses, altimeters, and airspeed indicators, sailplane pilots rely on variometers, hypersensitive vertical speed indicators, to measure the climb or sink rate of the sailplane. The “vario,” Ossorio tells me, enables him to detect if he’s entering a rising or falling air mass.

As we prepare to take off, I begin a silent prayer requesting that we do not encounter any unanticipated falling air masses. But my entreaty is interrupted as the tow plane—a retired Pawnee crop duster with a 200-foot rope hitched to the glider—rumbles to life in front of us. “You get motion sick?” Ossorio asks as we move down the runway. “Sometimes,” I answer honestly.

Within seconds, we’re airborne, floating behind the Pawnee as it climbs into the sky over northeast Boulder. The plane veers right and we veer with it, the Eastern Plains stretching out to my left. I stare out the right side of the canopy and watch Boulder’s buildings and homes shrink to the size of Monopoly pieces. At the southernmost edge of town, the Pawnee makes a sharp right and we fly straight for the mountains.

“Drop the tow,” Ossorio instructs me. I reach for a yellow knob and hesitate, glancing at the rope that’s connecting our glider to the engine-powered plane in front of us. I remind myself to breathe, then pull the knob. The rope releases and falls away from us. The Pawnee banks left and disappears. The only sound now is the wind.

In Boulder, and elsewhere for that matter, sailplaning is regarded as a predominantly intellectual pursuit. Joining one of the local clubs isn’t terribly expensive, and, as such, pilots often get together to geek out on the latest technology and techniques developed to push the limits of distance, height, and speed. But in the air with Ossorio, I’m admittedly more interested in the scenery than in the science. At an altitude of about 9,000 feet, we’re above the haze, and the view is crystal clear. Ossorio points the glider north, tracing the rocky ridgeline of the foothills. To my left, forested hillsides give way to the high Rockies, their snowcapped peaks stretching to the horizon. To my right lies the city of Boulder, and beyond it, expansive golden plains punctuated by an occasional glimmering lake. I catch sight of a hawk, wings spread, cruising on the same invisible current of air we are.

“We’re getting some good lift right now,” Ossorio says, “about two to three knots.” My stomach turns as we rise, then circle back to buzz a half-dozen hikers waving to us from the summit of 8,461-foot Bear Peak. It’s thrilling—and a bit nauseating. Ossorio asks if I’m up for some aerobatics—sailplanes can do loops, rolls, and wingovers, just like ordinary airplanes—but I confess that I’m dealing with impending motion sickness. Ossorio is kind enough not to push me and offers an unexpected way to avoid getting airsick: “Come back and learn to fly,” he says. “It’s different when you’re the driver.”

After a 30-some-minute flight, Ossorio swerves right to bring us back to the airport. As we head for home, I remember Ossorio telling me earlier that our sailplane has a 44:1 glide ratio: It can glide 44 miles horizontally for every mile of altitude. I spy the Boulder Municipal Airport and figure we must be closer than 44 miles. But before I can ask Ossorio, movement on the wing catches my eye. The spoiler flaps open, creating the drag that will prevent us from overshooting the landing.

We touch down much more smoothly than I expect, and I’m full of questions about how Ossorio orchestrated the landing. He leads me back to the picnic table to explain the technique, but a handful of other pilots gather to chat and ask about my ride. A 32-year-old engineer named Ben Jordan from Louisville tells me he’s working on his PVT-G (a private pilot’s license for gliders), while two other pilots talk about the exploits of a club called SoaringNV out of Minden, Nevada. The vibe is relaxed and jovial. I get the sense the north side of the Boulder Municipal Airport is a popular hangout in the summer. Ossorio confirms it and says, “Welcome to the club.”

Jayme Moye is a Boulder-based freelance writer who frequently contributes to the magazine. Email her at