It is the longest blade the UMaine Advanced Structures and Composites Centre has tested at the facility in the northeast of the country.
A spokesperson for the facility said it was one of only two sites in the US, which can test wind turbine components of this size. It also has the capability to test turbine towers and foundations.
Separatly, UMaine is leading the Maine Aqua Ventus consortium developing the Aqua Ventus 1 floating offshore turbine platform. The project missed out on a $47 million Department of Energy grant in May.
The university has a one-eighth-scale prototype of the floating platform, off the coast of Maine. It started operating last year and was the first offshore wind turbine to generate electricity for the grid in America.