Non-Towered Airports: Exploring The Uncontrolled Skies

Non-towered airports, also known as uncontrolled airports, are airports without a control tower or air traffic control (ATC) unit. In the United States alone, there are close to 20,000 non-towered airports, compared to only about 500 airports with control towers. Non-towered airports present unique challenges and considerations for pilots, including the need to self-announce their location and intentions, follow recommended operations and communications procedures, and maintain situational awareness without the assistance of air traffic controllers. Examples of busy non-towered airports include SZP and CCB in Southern California, and Peter O'Knight and VDF near Tampa.

Pilots must obtain clearances from a remote air traffic control unit

Non-towered airports are airports without a control tower or air traffic control (ATC) unit. In the United States alone, there are close to 20,000 non-towered airports, whereas there are only about 500 airports with control towers. Airports with control towers that do not have 24/7 ATC service follow non-towered airport procedures when the tower is closed but the airport remains operational.

At non-towered airports, pilots must follow recommended operations and communications procedures for airports without a control tower. These procedures vary from country to country but typically include standard arrival and departure procedures, as well as common communications phraseology via radio transmissions over a common frequency. For example, a Common Traffic Advisory Frequency (CTAF) is used in the US, Canada, New Zealand, and Australia.

Clearances issued by ATC are based on known traffic and airport conditions. ATC authorizations are intended to prevent collisions between aircraft by allowing them to proceed under specified conditions within controlled airspace. While ATC provides these authorizations, the pilot-in-command is directly responsible for the operation of the aircraft and must request an amended clearance if the ATC clearance would cause them to deviate from a rule or regulation or place the aircraft in jeopardy.

Radio operators issue advisories, but aircraft must make radio contact

In aviation, a non-towered airport is an airport without a control tower or air traffic control (ATC) unit. In the United States, there are close to 20,000 non-towered airports, compared to just 500 airports with control towers. At non-towered airports, pilots follow recommended operations and communications procedures, which vary from country to country. These procedures may include standard arrival and departure protocols, as well as common communications phraseology via radio transmissions over a common frequency.

Radio operators, such as those from fixed-base operators, issue advisories to pilots regarding weather conditions, runway status, traffic, and other pertinent information. However, these radio operators cannot provide clearances or instructions. It is mandatory for aircraft to establish radio contact with the ground station before operating within the airport's control zone. Pilots must communicate their position and coordinate with other pilots to determine the safest approach, minimising the potential for conflicts with other aircraft.

Radio communication is critical in the ATC system, fostering a strong link between pilots and controllers. Pilots must acknowledge each radio transmission from ATC using their aircraft call sign and keep messages concise. Controllers need to understand pilots' intentions to effectively execute their duties. Similarly, pilots must comprehend controllers' instructions to ensure safe operations.

In some cases, pilots can obtain clearances through radio, phone, or a local flight service station. Departing aircraft may level off below controlled airspace before requesting clearance to climb further. Certain countries, like Canada and Norway, employ mandatory frequency airports (MF) or mandatory traffic advisory airports (MTAF), which function similarly to towered airports. Many non-towered airports utilise radio-to-ground operations like UNICOM to assist aircraft with arrivals, departures, or ground manoeuvres.

Pilots should be prepared for the additional time to receive an IFR clearance

Non-towered airports are airports without a control tower or air traffic control (ATC) unit. In the United States alone, there are close to 20,000 non-towered airports, compared to just 500 airports with control towers. When an airport's tower closes, it may revert to Class E to the surface, Class G airspace, or a combination of both, with a Class E Instrument Flight Rules (IFR) corridor down to 700 feet above ground level.

At non-towered airports, pilots must follow recommended operations and communications procedures. These procedures vary from country to country but may include standard arrival and departure procedures, as well as common communications phraseology via radio transmissions over a common frequency. For example, a Common Traffic Advisory Frequency (CTAF) is used in the US, Canada, New Zealand, and Australia.

Pilots should be prepared for the additional time it may take to receive an IFR clearance from center controllers when departing from a non-towered airport. There are several ways to obtain an IFR clearance at a non-towered airport:

• Calling Flight Service on a pay phone: In the past, pilots would have to call Flight Service on a pay phone, which could be located a mile or more away from the airport ramp. The briefer would then contact ATC and relay the clearance to the pilot. The pilot would then have to run back to the airplane and take off before the clearance expired.
• Using a cell phone: With the widespread availability of cell phones, pilots can now easily call for an IFR clearance from anywhere, even while sitting in the airplane at the end of the runway.
• Calling ATC directly: Since 2019, the FAA has been publishing phone numbers for ATC facilities that pilots can use to obtain clearances directly. These phone numbers are available in the chart supplement (the old A/FD) and most aviation apps.

In summary, pilots operating at non-towered airports should be prepared for potential delays in receiving IFR clearances. By utilizing modern communication tools and staying familiar with specific airport procedures, pilots can effectively navigate the challenges posed by non-towered airports.

Airports may be considered for a tower when traffic volume is too high

In aviation, a non-towered airport is an airport without a control tower or air traffic control (ATC) unit. In the United States, there are approximately 20,000 non-towered airports, compared to only 500 airports with control towers. Airports with a control tower that does not have 24/7 ATC service follow non-towered airport procedures when the tower is closed but the airport remains open, such as at night.

At non-towered airports, pilots follow recommended operations and communications procedures for airports without a control tower. These procedures can include standard arrival and departure protocols, as well as common communications phraseology via radio transmissions over a common frequency. For instance, a Common Traffic Advisory Frequency (CTAF) is used for radio communication in the United States, Canada, New Zealand, and Australia.

Non-towered airports may pose challenges for pilots, requiring them to maintain a high degree of situational awareness and cooperation with other pilots. Pilots must also rely on tools like radio communication and visual observation to ascertain the positions of other aircraft. Failure to use radios to report positions and intentions within the airspace can lead to hazardous situations and collisions, as seen in the 1996 incident at Quincy Airport in Illinois.

When the traffic volume at a non-towered airport becomes too high for safe and efficient operations, or when there is a significant mix of aircraft types and speeds, the consideration for adding a control tower arises. However, constructing a tower and paying controllers' salaries can be financially challenging. Additionally, aviation regulations or local opposition may pose further obstacles to establishing a control tower.

Non-towered airports have standard arrival and departure procedures

A non-towered airport is an airport without a control tower or air traffic control (ATC) unit. In the United States alone, there are close to 20,000 non-towered airports, compared to just 500 airports with control towers. Airports with control towers that don't have 24/7 ATC service follow non-towered airport procedures when the tower is closed but the airport remains operational, such as at night.

At non-towered airports, pilots follow recommended operations and communications procedures for airports without a control tower. These procedures vary from country to country but often include standard arrival and departure procedures, as well as common communications phraseology via radio transmissions over a common frequency. A common traffic advisory frequency (CTAF) is used in the US, Canada, New Zealand, and Australia. Pilots may obtain clearances by radio, phone, or through a company dispatcher or local flight service station. In some cases, departing aircraft may take off and level out below the floor of controlled airspace, then radio for a clearance to climb further.

Non-standard departures from non-towered airports can significantly increase the risk of collisions with inbound traffic. Pilots should adhere to standard departure procedures, such as taking off into the wind and climbing straight out before making any turns until 300 feet above the TPA. Pilots should also be prepared for the additional time it may take to receive an IFR clearance from center controllers. When approaching a non-towered airport, crews should keep their eyes outside the cockpit to visually identify other traffic and monitor radio communications to ascertain the positions of nearby aircraft.

The Federal Aviation Administration (FAA) in the US has closed approximately 170 air traffic control towers due to budget sequestration, resulting in busier airports becoming non-towered. This has led to an increased need for pilots to be familiar with specific information about their destination airport, such as the exact procedures for each airport listed in the FAA's Airport/Facility Directory, or A/FD.

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