More than 30 controllers and supervisors all work at the top level of the tower, meticulously managing approaching and departing air traffic, 24 hours a day, seven days a week.
At any given time, up to nine controllers can be up top managing air traffic operations and talking with pilots.
The tower cab itself has 1,162-square feet of floor space, with a 360-degree view of the airport, 19 stories up. Just below the top level of the tower sits the Phoenix TRACON, or Terminal Radar Approach Control.
A different set of controllers in the TRACON monitor and talk with aircraft approaching Sky Harbor or aircraft passing through Arizona airspace, along with supporting smaller airports.
The air traffic control tower at Sky Harbor ranks between the 8th and 12th busiest tower in the country.