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Air Traffic Services Process Brief -- Criteria For Establishing Air Traffic Control Towers and the Contract Tower Program

Air Traffic Services Process Brief

Criteria For Establishing Air Traffic Control Towers and the Contract Tower Program

The Issue

Air traffic control towers (ATCTs) are established at airports to provide for a safe, orderly, and expeditious flow of traffic on, and in the vicinity of, an airport. Class D airspace surrounding the airport from the surface to 2,500 feet above the airport elevation (charted in mean sea level) is usually established in conjunction with a new ATCT. Many of the new control towers are part of the Federal Contract Tower Program.

The Importance to Our Members

Establishing a control tower at an airport that was previously uncontrolled will change the operating environment and procedures for pilots flying to and from the airport. Because air traffic operations are not the only factor to consider when establishing a control tower, pilots often have questions about the criteria the Federal Aviation Administration (FAA) uses to establish an air traffic control tower.


The FAA has the authority to establish control towers or discontinue control tower services through the National Airspace System when activity levels and safety considerations merit such action. Criteria for establishing a control tower was initially developed and published in 1951. Current guidelines lie with the FAA Office of Aviation Policy and Plans (APO-200). The general qualifications necessary to become a candidate site for establishment or discontinuance of a control tower are published in the Federal Aviation Regulations (FAR) Part 170, "Establishment And Discontinuance Criteria For Air Traffic Control Services And Navigational Facilities." The criteria and computation methodology are outlined in the FAA report titled " Establishment And Discontinuance Criteria For Air Traffic Control Towers" (Report No. FAA-APO-90-7).


According to FAR Part 170.13, the following criteria, along with general facility establishment standards, must be met before an airport can qualify for a control tower:

  1. The airport, whether publicly or privately owned, must be open to and available for use by the public as defined in the Airport and Airway Improvement Act of 1982;
  2. The airport must be part of the National Plan of Integrated Airport Systems;
  3. The airport owners/authorities must have entered into appropriate assurances and covenants to guarantee that the airport will continue in operation for a long enough period to permit the amortization of the control tower investment;
  4. The FAA must be furnished appropriate land without cost for construction of the control tower; and
  5. The airport must meet the benefit-cost ratio criteria specified herein utilizing three consecutive FAA annual counts and projections of future traffic during the expected life of the tower facility. (An FAA annual count is a fiscal year or a calendar year activity summary. Where actual traffic counts are unavailable or not recorded, adequately documented FAA estimates of the scheduled and nonscheduled activity may be used.)

The FARs specifically state that an airport is not guaranteed to receive a control tower, even if the airport meets all the criteria listed above. This is where the contract tower program comes in. The FAA, responding to an airport sponsor's request for an air traffic control tower, can elect to establish a contract tower. The FAA can either elect to pay for the service in its entirety, or enter into a cost-sharing agreement with the sponsor, depending on the results of the benefit-cost analysis. Typically, the airport sponsor is responsible for 10 percent of the cost of construction and operations.

The Benefit-Cost Ratio Explained

The FAA prescribes benefit-cost-based criteria for establishment and discontinuance of control tower facilities as part of its mission to maximize safety and efficiency throughout the airport and airway system consistent with available resources. Decisions to establish and operate control towers have been, and will continue to be, based on benefits exceeding costs of such actions.

The criteria and computation methods used in determining the eligibility of terminal locations for VFR tower establishment and discontinuance is based on economic analysis of the costs and benefits of a control tower. The criterion compares the present value of VFR tower benefits (BPV) at a site with the present value of VFR tower costs (CPV) over a 15-year time frame. A location is eligible for a control tower when the benefits derived from operating the tower exceed the installation and operation costs. This is the same as saying that values of benefits exceed costs, or BPV/CPV≥1.00.

Site-specific activity forecasts are used to estimate three categories of tower benefits:

  • Benefits from prevented collisions between aircraft.
  • Benefits from other prevented accidents.
  • Benefits from reduced flying time.

Explicit dollar values are assigned to the prevention of fatalities and injuries and time saved.

Tower establishment costs include:

  • Annual operating costs: staffing, maintenance, equipment, supplies, and leased services.
  • Investment costs: facilities, equipment, and operational start-up.

The Federal Contract Tower (FCT) Program

The FCT has been in place since 1982 and currently provides for the contract operation of air traffic control (ATC) services at over 225 airports. A centralized program office in Washington, D.C., manages the FCT Program. The office develops the policies and procedures that support the program, provides technical guidance to contractors, and ensures the safe, orderly, and expeditious movement of people and aircraft at each contract tower.

AOPA's Position

While the program has received high marks from the Department of Transportation (DOT) inspector general (IG), Congress, and the National Transportation Safety Board (NTSB), AOPA continues to monitor the progress and any expansion of the program to ensure our members receive an adequate level of service comparable to FAA-managed towers.

FAA Stated Cost Savings

The FAA and DOT state significant cost savings using contracted tower services over FAA-staffed control towers. The FAA reports the average operating cost for an FAA-staffed Level I tower is about $450,000 per year, compared to $250,000 for a contract tower (a Level I tower has a traffic density of 0 to 34.99 operations an hour, a measure derived from a formula that includes hours of operation, a specific number of high-count days per year, and other factors). Contractors can utilize part-time controllers, assign controllers to more than one facility, and adjust staffing to reflect seasonal variations in traffic. This flexibility efficiency is not available to the FAA. Costs are further reduced because most contract employees have previously been trained as air traffic controllers and funds are not required to move people to higher level facilities.

Associated Links

  1. Part 170 - Establishment and Discontinuance Criteria For Air Traffic Control Services and Navigational Facilities
  2. FAA Office of Aviation Policy and Plans (APO-200) Establishment and Discontinuance Criteria For Airport Traffic Control Towers (Report No. FAA-APO-90-7) (requires Adobe Reader)
  3. National Plan of Integrated Airport Systems Web site
  4. Contract Tower Association Web site

Updated Monday, December 05, 2005 12:15:15 PM