A blade pitch drive comprising a driver sprocket, a driven sprocket, a toothed belt trained between the driver sprocket and driven sprocket, the toothed belt having a free span between the driver sprocket and driven sprocket, the free span having an arcuate form when the free span is in a slack condition, the toothed belt having a second span between the driver sprocket and driven sprocket in a tight condition when the free span is in a slack condition, and the free span operable as the second span and the second span operable as the free span according to an operating direction of the drive.
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