Rapid expansion in passenger traffic has led to increasing commercial use of the south side of the airport. This was previously used for general aviation, but is now used for freight, mail and corporate flights. This is partially due to difficulties obtaining departure and arrival slots for light aircraft traffic, which need to be separated from larger aircraft to protect against wake turbulence. As part of the Airport Master Plan, the south-side area is to be expanded with maintenance facilities including new hangar and apron areas.