A recent report (PDF) from the Transportation Department's Office of Inspector General found that contract towers are cheaper to operate than FAA towers. The contract towers also had a lower rate of safety incidents compared to similar FAA towers. "On average, a contract tower cost about $1.5 million less to operate than a comparable FAA tower, mainly due to lower staffing and salary levels," according to the OIG. The OIG made several suggestions to the FAA to improve the program, including strengthening financial oversight and implementing voluntary safety reporting systems at the towers.
Contract towers are used at 250 low-activity U.S. airports that otherwise wouldn't have air traffic services. The OIG based its cost comparison on 30 randomly selected contract towers and 30 FAA towers with a comparable level of operations. For the safety study, the FAA reviewed 240 of the contract towers, which reported a total of 197 safety incidents, compared to 362 incidents at 92 similar FAA towers. The OIG said the FAA should include contract towers in voluntary reporting systems for safety incidents, such as the Air Traffic Safety Action Program currently in place at all FAA facilities.