Air Traffic Control and the National Airspace System (Part One)

The primary purpose of the ATC system is to prevent a collision between aircraft operating in the system and to organize and expedite the flow of traffic. In addition to its primary function, the ATC system has the capability to provide (with certain limitations) additional services. The ability to provide additional services is limited by many factors, such as the volume of traffic, frequency congestion, quality of radar, controller workload, higher priority duties, and the pure physical inability to scan and detect those situations that fall in this category. It is recognized that these services cannot be provided in cases in which the provision of services is precluded by the above factors.

 

Consistent with the aforementioned conditions, controllers shall provide additional service procedures to the extent permitted by higher priority duties and other circumstances. The provision of additional services is not optional on the part of the controller, but rather is required when the work situation permits. Provide ATC service in accordance with the procedures and minima in this order except when:

  1. A deviation is necessary to conform to ICAO Documents, National Rules of the Air, or special agreements where the United States provides ATC service in airspace outside the country and its possessions
  2. Other procedures/minima are prescribed in a letter of agreement, FAA directive, or a military document
  3. A deviation is necessary to assist an aircraft when an emergency has been declared

Coordinating the Use of Airspace

ATC is responsible for ensuring that the necessary coordination has been accomplished before allowing an aircraft under their control to enter another controller’s area of jurisdiction.

Before issuing control instructions directly or relaying through another source to an aircraft that is within another controller’s area of jurisdiction that will change that aircraft’s heading, route, speed, or altitude, ATC ensures that coordination has been accomplished with each of the controllers listed below whose area of jurisdiction is affected by those instructions unless otherwise specified by a letter of agreement or a facility directive:

  1. The controller within whose area of jurisdiction the control instructions are issued
  2. The controller receiving the transfer of control
  3. Any intervening controller(s) through whose area of jurisdiction the aircraft will pass

If ATC issues control instructions to an aircraft through a source other than another controller (e.g., Aeronautical Radio, Incorporated (ARINC), FSS, another pilot), they ensure that the necessary coordination has been accomplished with any controllers listed above, whose area of jurisdiction is affected by those instructions unless otherwise specified by a letter of agreement or a facility directive.

 

Operating in the Various Types of Airspace

It is important that pilots be familiar with the operational requirements for each of the various types or classes of airspace. Subsequent sections cover each class in sufficient detail to facilitate understanding regarding weather, type of pilot certificate held, and equipment required.

Basic VFR Weather Minimums

No pilot may operate an aircraft under basic VFR when the flight visibility is less, or at a distance from clouds that is less, than that prescribed for the corresponding altitude and class of airspace. [Figure 15-8] Except as provided in 14 CFR part 91, section 91.157, “Special VFR Weather Minimums,” no person may operate an aircraft beneath the ceiling under VFR within the lateral boundaries of controlled airspace designated to the surface for an airport when the ceiling is less than 1,000 feet. Additional information can be found in 14 CFR part 91, section 91.155(c).

Figure 15-8. Visual flight rule weather minimums.

Figure 15-8. Visual flight rule weather minimums. [click image to enlarge]

Operating Rules and Pilot/Equipment Requirements The safety of flight is a top priority of all pilots and the responsibilities associated with operating an aircraft should always be taken seriously. The air traffic system maintains a high degree of safety and efficiency with strict regulatory oversight of the FAA. Pilots fly in accordance with regulations that have served the United States well, as evidenced by the fact that the country has the safest aviation system in the world.

All aircraft operating in today’s National Airspace System (NAS) has complied with the CFR governing its certification and maintenance; all pilots operating today have completed rigorous pilot certification training and testing. Of equal importance is the proper execution of preflight planning, aeronautical decision-making (ADM) and risk management. ADM involves a systematic approach to risk assessment and stress management in aviation, illustrates how personal attitudes can influence decision-making, and how those attitudes can be modified to enhance safety in the flight deck. More detailed information regarding ADM and risk mitigation can be found in Chapter 2, “Aeronautical Decision-Making.”

Pilots also comply with very strict FAA general operating and flight rules as outlined in the CFR, including the FAA’s important “see and avoid” mandate. These regulations provide the historical foundation of the FAA regulations governing the aviation system and the individual classes of airspace. Figure 15-9 lists the operational and equipment requirements for these various classes of airspace. It is helpful to refer to this figure as the specific classes are discussed in greater detail.

Figure 15-9. Requirements for airspace operations.

Figure 15-9. Requirements for airspace operations. [click image to enlarge]

Class A

Pilots operating an aircraft in Class A airspace must conduct that operation under IFR and only under an ATC clearance received prior to entering the airspace. Unless otherwise authorized by ATC, each aircraft operating in Class A airspace must be equipped with a two-way radio capable of communicating with ATC on a frequency assigned by ATC. Unless otherwise authorized by ATC, all aircraft within Class A airspace must be equipped with the appropriate transponder equipment meeting all applicable specifications found in 14 CFR part 91, section 91.215. Additionally, beginning January 1, 2020, aircraft operating in the Class A airspace described in 14 CFR part 91, section 91.225, must have ADS-B Out equipment installed, which meets the performance requirements of 14 CFR part 91, section 91.227.

 

Class B

All pilots operating an aircraft within a Class B airspace area must receive an ATC clearance from the ATC facility having jurisdiction for that area. The pilot in command (PIC) may not take off or land an aircraft at an airport within a Class B airspace unless he or she has met one of the following requirements:

  1. A private pilot certificate
  2. A recreational pilot certificate and all requirements contained within 14 CFR part 61, section 61.101(d), or the requirements for a student pilot seeking a recreational pilot certificate in 14 CFR part 61, section 61.94.
  3. A sport pilot certificate and all requirements contained within 14 CFR part 61, section 61.325, or the requirements for a student pilot seeking a recreational pilot certificate in 14 CFR part 61, section 61.94, or the aircraft is operated by a student pilot who has met the requirements of 14 CFR part 61, sections 61.94 and 61.95, as applicable.

Unless otherwise authorized by ATC, all aircraft within Class B airspace must be equipped with the applicable operating transponder and automatic altitude reporting equipment specified in 14 CFR part 91, section 91.215(a) and an operable two-way radio capable of communications with ATC on appropriate frequencies for that Class B airspace area. Additionally, beginning January 1, 2020, aircraft operating in the Class B airspace described in 14 CFR part 91, section 91.225, must have ADS-B Out equipment installed, which meets the performance requirements of 14 CFR part 91, section 91.227.