A wind turbine blade came crashing to the ground Wednesday, halting energy production at a small-scale wind farm southwest of Wyanet because of what may be a defective design. In all, four turbines on Richard Shertz's property - all part of the AgriWind facility in central Bureau County - have stopped turning after a blade on top of one of the towers broke off about 9:30 a.m. "It was the loudest noise I've ever heard," he said. "I thought it was thunder."

Shortly after 9 a.m. Wednesday, a rotating blade on a wind turbine at Schertz's farm broke off, plunging to the earth in a cornfield about 150 feet west of the turbine. ...The spokesperson said the investigation into this turbine had just started, but the company was in the middle of a blade retrofit program across the United States to correct an "unfortunate" design issue in the first generation of this blade.