Consolidation Coal Company Mine No. 11, Aerovane Fan, East side of State Route 936, Midlothian, Allegany County, MD

Significance: The aerovane fan illustrates the evolution of mine ventilation in the United States during the first half of the twentieth century. It is an example of an axial flow fan. These fans generally replaced centrifugal fans for mine ventilation because of their small size and their ability to produce high air pressure at slower speeds. These improvements enabled these fans to provide improved mine ventilation and improve health and safety of mine workers. This aerovane fan, typical of mine ventilation fan designs of its period, was patented by Theodore L. Troller.
Survey number: HAER MD-87-B