Chart Smart: VFR Sectional Concentrated Obstructions

What does the boxed, highlighted altitude figure indicate to the southwest of the Sidney Municipal Airport (KSNY) near Sidney, Nebraska? Note, there are several other examples of the same altitude figures on the chart.

The boxed, highlighted altitudes indicates the presence of concentrated obstructions that are part of a wind turbine farm. Concentrated obstructions of wind turbine farms are portrayed by an overlying hatched area and dotted outline to represent the approximate parameters of the farm. One or more single turbine symbols will populate the farm. A boxed elevation figure representing the MSL elevation of the highest wind turbine within the area is placed inside the farm or, if space is limited, just outside. In this examply, the elevation of the highest wind turbine is 5,248′. Pilots are reminded that wind turbine blades and/or blade tips are not lighted. Wind turbine obstruction lights are located on top of the nacelle (generator) at the hub of wind turbines, which in some cases can be 200-300’ below the rotating blade tips.

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Eric Radtke

It was his first airplane trip at age seven that made Eric decide to become a pilot. "While boarding the airplane, a flight attendant noticed my interest in the flight deck and urged me to go talk to the pilot. I give a lot of credit to that pilot for my career choice." Eric earned a bachelor’s degree in finance and went on to an airline career. He learned to fly at Sporty’s as part of the University of Cincinnati’s Professional Pilot Program, an initiative he later directed.Eric now manages Sporty’s media network including FlightTrainingCentral.com. In addition, Eric serves as a Captain in a Cincinnati-based corporate flight department.

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