The HHs10y Class is a class of heavy switching locomotives designed by Reginald Thornton at the Eastern & Atlantic's Trenton Works.
The HHe9y Class was produced in the mid 20's that was used around New york for transfer work. In the late 1920's, the large marshalling yards on the E&A, especially in the hump yards around Roanoke, required much larger locomotives for switching work. Thus, the design was modified and went into produced as the HHs10y Class.
16 were built at the Eastern & Atlantic's Charlotte Works.