FAA staff spot approaching aircraft at the Fisk VFR Approach Control, west of Oshkosh. Ray Thyfault (far right) is one of two Operations Supervisors at Fisk Control. Photo by David Sakrison

If you fly VFR into EAA AirVenture Oshkosh, your first point of contact with Air Traffic Control (ATC) is a small group of controllers perched on a grassy hillside a few air miles southwest of Wittman Field. At Fisk Control, approach controllers ensure proper spacing of aircraft and direct each aircraft to a specific active runway.

Fisk Control began operation on Friday, July 25, at 6 a.m. and will continue to operate, from 7 a.m. to 8 p.m. (except during each afternoon’s air show), every day through Sunday, August 3. At times, during AirVenture, it will be the busiest ATC approach control center anywhere in the world.

Ray Thyfault is one of two Operations Supervisors at Fisk Control. He has been an EAA member for 35 years and an air traffic controller at the EAA fly-in for 16 years. During the rest of the year, he is a controller at the Kalamazoo, Michigan, tower. At Fisk, he supervises four-person teams of controllers. Sixteen such teams rotate during the event.

Each team works a half-day at Fisk (morning or afternoon). The teams also rotate through the Oshkosh control tower; the temporary tower at the Fond du Lac airport, south of Oshkosh; and the Mobile Communications Workstations (known affectionately to the controllers as "MooCoWs") abeam each active runway at Wittman Field. At Fisk, each team consists of a leader and "veteran" (each with at least three years of ATC experience at AirVenture), a "limited" with at least two years, and a "rookie" who is an ATC first-timer at AirVenture.

Under the AirVenture NOTAM (Notice to Airmen), all aircraft (except warbirds) coming to Oshkosh under visual flight rules (VFR) begin their approach over the city of Ripon, about 16 air miles to the southwest. They follow the Wisconsin & Southern rail line from Ripon to Fisk, in single file, maintaining one half-mile of horizontal separation, at 1,800 feet MSL (above mean sea level) and at a speed of 90 knots. Aircraft that are too fast to maintain 90 knots approach Fisk at 2,300 feet MSL and 135 knots. At Fisk, the controllers assign each aircraft to an active runway and direct them to a base leg. On Sunday morning, they were directing aircraft to follow the railroad to Runway 27 or follow Fisk Road to Runway 36.

Thyfault says having two runways helps the controllers maintain the half-mile separation, even when over-eager pilots get bunched up. "Having an alternate runway takes care of 90 percent of the issues," he said. The most common "issue" is aircraft spacing. "There’s a wide range of abilities and anxiety levels among the pilots flying into AirVenture," he explained, "but they are all eager to cooperate with us. We couldn’t do this job without the pilots and their cooperation."

You can visit the Fisk Control. Take U.S. Highway 44 West to Fisk Road, then head north about a mile to the controllers’ hilltop perch. "We get lots of observers out here," say Thybault. "It’s quite a show."