(Example of a taxonomy under development for Air Traffic Control at MIT. Lincoln Laboratory)

Air defense
RT: Air traffic control (ATC)

Air traffic control (ATC)
NT1: Air traffic control systems
  NT2: Airborne collision avoidance system
  NT2: Automatic dependent surveillance
  NT2: Automatic en route ATC
  NT2: Center TRACON automation system (CTAS)
  NT2: Cockpit weather information systems
  NT2: Corridor integrated weather system
  NT2: Display system replacement (DSR)
  NT2: Flight management systems
  NT2: Traffic and collision alerting system (TCAS)
NT1: Aircraft approach spacing
NT1: Aircraft tracking
NT1: Airport radar
  NT2: Airport surveillance radar (ASR)
  NT2: Mode S beacon radar
NT1: Collisions
  NT2: Bird-aircraft collisions
  NT2: Collision avoidance
    NT3: Airborne collision avoidance system
    NT3: Automatic dependent surveillance
NT1: Flight control
  NT2: Flight data
NT1: Ground based control
NT1: National Airspace System (NAS)
NT1: Runways
NT1: Traffic information service (TIS)
NT1: Traffic management
RT: Air defense
RT: Air transportation
RT: Aircraft
RT: Aircraft hazards
RT: Airline operations
RT: Airspace
RT: Attitude control
RT: Aviation meteorology
RT: Civil airspace
RT: Cold fronts
RT: Flight
RT: Navigation
RT: Surveillance radar
RT: Taxiing
RT: Transponders

Air traffic control systems
NT1: Airborne collision avoidance system
NT1: Automatic dependent surveillance
NT1: Automatic en route ATC
NT1: Center TRACON automation system (CTAS)
NT1: Cockpit weather information systems
NT1: Corridor integrated weather system
NT1: Display system replacement (DSR)
NT1: Flight management systems
NT1: Traffic and collision alerting system (TCAS)
BT1: Air traffic control (ATC)

Air transportation
RT: Air traffic control (ATC)

Airborne collision avoidance system
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)
BT1: Collision avoidance
  BT2: Collisions
    BT3: Air traffic control (ATC)

Aircraft
NT1: Aircraft approach spacing
RT: Air traffic control (ATC)
RT: Taxiing

Aircraft approach spacing
BT1: Air traffic control (ATC)
BT1: Aircraft

Aircraft hazards
RT: Air traffic control (ATC)
RT: Flight hazards

Aircraft tracking
BT1: Air traffic control (ATC)

Airline operations
RT: Air traffic control (ATC)

Airport radar
NT1: Airport surveillance radar (ASR)
NT1: Mode S beacon radar
BT1: Air traffic control (ATC)

Airport surveillance radar (ASR)
BT1: Airport radar
  BT2: Air traffic control (ATC)

Airspace
RT: Air traffic control (ATC)

Attitude control
RT: Air traffic control (ATC)

Automatic dependent surveillance
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)
BT1: Collision avoidance
  BT2: Collisions
    BT3: Air traffic control (ATC)

Automatic en route ATC
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)

Aviation meteorology
RT: Air traffic control (ATC)

Bird-aircraft collisions
BT1: Collisions
  BT2: Air traffic control (ATC)
BT1: Flight hazards

Center TRACON automation system (CTAS)
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)
	SN:	 The Center-TRACON Automation System, or CTAS, is a
    set of tools designed to help air traffic
    controllers manage the increasingly complex air
    traffic flows at large airports. The tools in CTAS
    benefit air traffic controllers by reducing stress
    and workload, and benefit air travelers by
    reducing delays and increasing safety.

Civil airspace
RT: Air traffic control (ATC)

Cockpit weather information systems
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)

Cold fronts
RT: Air traffic control (ATC)

Collision avoidance
NT1: Airborne collision avoidance system
NT1: Automatic dependent surveillance
BT1: Collisions
  BT2: Air traffic control (ATC)

Collisions
NT1: Bird-aircraft collisions
NT1: Collision avoidance
  NT2: Airborne collision avoidance system
  NT2: Automatic dependent surveillance
BT1: Air traffic control (ATC)
RT: Traffic and collision alerting system (TCAS)

Corridor integrated weather system
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)

Display system replacement (DSR)
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)

Flight
RT: Air traffic control (ATC)

Flight control
NT1: Flight data
BT1: Air traffic control (ATC)
RT: Flight paths

Flight data
BT1: Flight control
  BT2: Air traffic control (ATC)

Flight hazards
NT1: Bird-aircraft collisions
RT: Aircraft hazards

Flight management systems
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)

Flight paths
RT: Flight control

Flight tests

Ground based control
BT1: Air traffic control (ATC)

Landing aids
RT: Runways

Mode S beacon radar
BT1: Airport radar
  BT2: Air traffic control (ATC)

National Airspace System (NAS)
BT1: Air traffic control (ATC)

Navigation
RT: Air traffic control (ATC)

Runways
BT1: Air traffic control (ATC)
RT: Landing aids
RT: Taxiing

Surveillance radar
RT: Air traffic control (ATC)

Taxiing
RT: Air traffic control (ATC)
RT: Aircraft
RT: Runways

Traffic and collision alerting system (TCAS)
BT1: Air traffic control systems
  BT2: Air traffic control (ATC)
RT: Collisions

Traffic information service (TIS)
BT1: Air traffic control (ATC)

Traffic management
BT1: Air traffic control (ATC)

Transponders
RT: Air traffic control (ATC)