The Greeneville Municipal Airport Authority is exploring options for building new hangars at Greeneville Municipal Airport.The hangars being considered would be “box hangars” which are able to hold multiple airplanes, according to Greeneville Airport Manager Steven Neesen.The rough estimate for building the hangars as three separate units was $2.3 million, and the estimate for building the hangers side by side with dividing walls was $2 million.The idea was presented this week to the airport board.