ATS Services and Positions—Vocabulary Flashcards

Services Provided by ATS Personnel

  • ATS personnel provide four distinctive types of services to pilots, vehicle operators, and other air/ground traffic: information services, advisory services, control services, and alerting services.

  • All ATS personnel provide information and alerting services.

  • Air traffic controllers provide control services; flight service specialists provide advisory services.

  • Flight service specialists also provide control services, but to vehicles only.

  • Overview (Figure 1): the four distinct types of services provided by ATS personnel include Information Services, Advisory Services, Control Services, and Alerting Services.

    • Information Services: Flight Information Service Enroute (FISE), Pilot Briefing Service (PBS), Remote Airport Advisory Service (RAAS), Airport Advisory Service (AAS)

    • Control Services: Vehicle Control Service (VCS), Airport Control Service, Terminal Control Service, Area Control Service

    • Alerting Services: alerting safety services and SAR coordination

Information Services

  • All ATS units provide information services.

  • Flight service specialists and air traffic controllers keep pilots informed of information useful for safe operations.

  • Information service is provided before departure and during flight, inside or outside controlled airspace.

  • Information may include:

    • Traffic and advisory information

    • Adverse weather conditions

    • Unserviceability of navigational aids (NAVAIDs)

    • Alerting services

    • Flight hazards

Flight Information Service Enroute (FISE)

  • Provided by flight service specialists in Flight Information Centres (FICs).

  • Provides information about conditions along the route of flight that may affect feasibility or safety of operations.

  • Includes information relevant to flight safety, such as:

    • Serviceability of NAVAIDs

    • Hazards like lightning, birds, fuel dumping, unmanned free balloons, parachute descents

Pilot Briefing Service (PBS)

  • Focus: ensure pilots receive all pertinent aeronautical and meteorological information prior to flight.

  • Provided by flight service specialists in FICs.

Advisory Services

  • Advisory services refer to information essential for the safe and efficient movement of arriving and departing aircraft.

  • RAAS (Remote Airport Advisory Service) vs AAS (Airport Advisory Service): RAAS is provided remotely (example: Sydney, NS via Charlottetown FSS).

  • AAS provides local weather and traffic information, runway conditions, wind, altimeter, and emergency assistance; provided by flight service specialists.

Remote Airport Advisory Service (RAAS)

  • RAAS is similar to AAS but delivered remotely.

  • Example: RAAS for Sydney, NS is provided by flight service specialists at the Charlottetown Flight Service Station.

Airport Advisory Service (AAS)

  • Includes information on local weather and traffic, runway conditions, wind, altimeter, and emergency assistance.

  • Provided by flight service specialists.

Control Services

  • Control services ensure separation between aircraft in the air, between ground vehicles and aircraft on the manoeuvring area, and between aircraft and vehicles on the ground.

  • Users must comply with control instructions (e.g., change altitude, stop a vehicle) unless safety is jeopardized or the action cannot be completed.

  • Objective: maintain a safe, orderly, and expeditious flow of traffic under control while prioritizing safety; traffic should move smoothly.

Vehicle Control Service (VCS)

  • Designed to eliminate potential collisions between ground traffic and aircraft on the manoeuvring area.

  • Provided by ground controllers at airports with control towers and by flight service specialists at airport advisory sites.

Airport Control Service

  • Provided by airport control tower controllers to aircraft and vehicles on the manoeuvring area and to aircraft operating in the vicinity of an airport.

  • Examples: issuing a turn on takeoff, instructing a pilot to follow a specific aircraft, routing a vehicle operator, or denying a pilot’s request for a manoeuvre.

  • Delivered by airport controllers who may work ground control, tower control, clearance delivery, or combinations of these.

Terminal Control Service

  • Controllers provide terminal control service to ensure separation between IFR aircraft and IFR/VFR aircraft as they arrive/depart airports in their area.

  • Located at Area Control Centres (ACCs) and known as terminal controllers.

Area Control Service

  • Controllers provide area control service to ensure separation between IFR and some types of VFR aircraft in their area of responsibility as they progress between airports.

  • Located at ACCs and known as enroute controllers.

Alerting Services

  • Alerting services notify appropriate safety services organizations about aircraft in need of search and rescue aid, and assist such organizations as required.

  • Provided for both IFR and VFR flight plans; progress of every flight is monitored from filing to flight plan closure to ensure safe arrival.

ATS Surveillance

  • ATS surveillance is used in the provision of ATS services.

  • Air traffic controllers and flight service specialists keep pilots informed based on surveillance display information.

  • Surveillance is provided by any ATS unit/sector equipped with surveillance hardware.

  • Examples of information derived from surveillance: traffic information, weather presence, obstructions, restricted areas, unknown targets.

ATS Surveillance Control Service

  • Only provided by ATC units/sectors equipped with surveillance.

  • Involves controlling aircraft by providing heading instructions (vectors) to establish required separation using surveillance-derived information.

ATS Positions

  • When providing air traffic services, at least one but potentially several ATS positions are involved in communicating with the aircraft.

  • It’s important to understand each position’s function and the method used to identify it in radio transmissions.

  • Common positions include:

    • Flight Service Specialist

    • Apron Advisory

    • Ground Control

    • Tower Control

    • Clearance Delivery

    • Terminal Arrival (Arrival) Control

    • Terminal Departure (Departure) Control

    • Surveillance Enroute (Enroute/ACC) control

  • The slides introduce flight service specialists, apron advisory, and the other positions as part of the ATS workflow.

Information Services at a Flight Information Centre (FIC)

  • A Flight Information Centre (FIC) is a key part of flight planning serving a large area; there are five FICs in Canada.

  • An FIC is not tied to a single airport or FIR; staff are called flight service specialists.

  • Services provided 24 hours a day:

    • Conduct pilot briefings

    • Accept and process flight plans

    • Communicate in-flight information

    • Relay ATC clearances

    • Assist aircraft in emergency situations

    • Provide alerting services and search for VFR aircraft

    • Monitor navigational aids (NAVAIDs)

    • Issue notices on airport conditions, NAVAID serviceability, and surface weather reports

    • Perform surface weather observations at some locations

  • Pilots (IFR or VFR) may contact an FIC for information or to communicate important ATS information; VFR pilots may contact for weather updates/file position reports.

  • FIC staff are identified as RADIO when communicating on a frequency.

  • Phraseology example: "HALIFAX LONDON RADIO, THIS IS SPEEDAIR SIX-ZERO-ZERO."

Information Services at a Flight Service Station (FSS)

  • FSSs are typically located at smaller airports with lower traffic density; staffed by flight service specialists; larger/busier airports use controllers.

  • FSS staff provide services to aircraft/vehicles operating at the airport and aircraft in the vicinity.

  • At an airport FSS location, FSS staff provide:

    • AAS and RAAS

    • Vehicle control

    • Accept and process flight plans

    • Relay ATC clearances

    • Assist aircraft in emergency situations

    • Alerting/search for VFR aircraft

    • Monitor NAVAIDs

    • Perform surface weather observations

  • Some airports have Remote Communications Outlets (RCO) allowing RAAS to cover remote airports (e.g., Charlottetown to Sydney, 225+ km away).

  • Unlike tower positions where two people may be working, most FSS operate with a single position.

  • Position identification for FSS on radio: RADIO

  • Phraseology example: “CHARLOTTETOWN RADIO, THIS IS JAZZ EIGHT-SIX-TWO-SEVEN.”

Services Provided to Departing Aircraft

  • After pilots file flight intentions, the flight service specialist creates a Flight Data Entry (FDE) and provides pertinent airport information to the pilot.

Services Provided to Arriving Aircraft

  • Upon arrival intentions, the FDE is created, and the pilot is provided with traffic and current airport information.

  • The FSS updates pilots en route with traffic, weather changes, and airport conditions as the aircraft approaches.

  • Aircraft in both cases communicate on frequencies identified by the radio position RADIO.

  • Phraseology example for arriving/departing: “CHARLOTTETOWN RADIO, THIS IS JAZZ EIGHT-SIX-TWO-SEVEN.”

Airport Control Services

  • Tower controllers operate at airports with ATC services; typically include two positions: GROUND and TOWER; some sites also have CLEARANCE DELIVERY.

  • Tower controllers manage the flow of traffic on the ground and in the air within the control zone around the airport.

  • Depending on staffing/traffic, a tower controller may handle: Tower Control, Ground Control, Clearance Delivery, or combinations.

Apron Advisory

  • At large airports, apron advisory assigns gates (e.g., Gate 34), issues pushback instructions, and provides advisory information on aircraft/vehicle activity on the apron.

  • Not provided by NAV CANADA; identified as APRON when communicating on the radio.

  • Phraseology example: "TORONTO APRON, THIS IS AIR CANADA FIVE-ZERO-ONE."

Clearance Delivery

  • In busier towers, clearance delivery issues IFR clearances, provides airport information to IFR and VFR pilots, creates/amends/deletes FDE strips, forwards FDE to ground controller, answers/initiates phone calls, coordinates with agencies, and performs clerical tasks.

  • If both apron advisory and clearance delivery exist, pilots decide which to contact first.

  • Aircraft cannot taxi off an apron without clearance; after clearance, pilots switch to ground or apron advisory frequencies as appropriate.

  • Clearance delivery is identified as CLEARANCE DELIVERY on radio.

  • Phraseology example: "OTTAWA CLEARANCE DELIVERY, THIS IS WESTJET SIX-ZERO-FOUR."

Ground Control

  • Ground controllers provide services typically handled by clearance delivery: issue airport information, taxi authorizations, vehicle movement authorizations, and coordinate with tower controllers.

  • After the pilot’s intention is known, FDE is created and the ground controller issues taxi clearances to move from apron to runway.

  • When the aircraft reaches the hold line, ground control may instruct the pilot to switch to the tower control frequency.

  • Ground control is identified as GROUND on radio.

  • Phraseology example: "FREDERICTON GROUND, THIS IS ENCORE WESTJET THREE-FOUR-ZERO-SEVEN."

Tower Control

  • Tower towers always have a tower controller on duty during operating hours.

  • Tower controllers issue take-off and landing clearances, pass traffic, ensure separation, coordinate with ground ACC/tower, provide information and alerting services.

  • Tower control is identified as TOWER on radio.

  • Phraseology example: "PILOT: THUNDER BAY TOWER, THIS IS BEARSKIN FIVE-TWO-ONE. / TOWER: BEARSKIN FIVE-TWO-ONE, THUNDER BAY TOWER, CLEARED FOR TAKEOFF RUNWAY ZERO-SEVEN."

Services Provided to Departing Aircraft (Tower)

  • After takeoff clearance, aircraft may be instructed to change to an ACC (Area Control Centre) frequency or stay on tower frequency depending on circumstances.

Services Provided to Arriving Aircraft (Tower)

  • Tower arrivals receive landing clearances, then are instructed to contact ground or ACC after landing and taxiing as appropriate.

  • Phraseology example: "PITT MEADOWS TOWER, THIS IS CHARLIE GOLF ALFA SIERRA QUEBEC, SIX MILES NORTH INBOUND FOR LANDING." / Tower: "… RUNWAY ONE-EIGHT WIND ONE-SIX-ZERO AT TEN, ALTIMETER 3001, CLEARED STRAIGHT IN, REPORT TWO MILES FINAL."

Terminal Control Services

  • High-traffic airports are surrounded by Terminal Control Areas (TCA).

  • A terminal control sector is established inside a TCA to provide control for IFR and VFR flights; an adjacent enroute sector may also provide terminal control.

  • Controllers providing terminal control work at ACCs.

  • Terminal control sectors may contain up to three separate positions operating simultaneously:

    • Departure control (separating IFR departures)

    • Arrival control (separating IFR arrivals)

    • Terminal surveillance (separating all VFR flights)

Terminal Control Sector Positions

  • The main responsibilities of terminal controllers include:

    • Separating IFR from IFR traffic, IFR from VFR, and VFR from VFR ( workload permitting )

    • Issuing clearances and instructions

    • Receiving arrivals and handing off departures according to procedures

    • Passing traffic, providing weather information, issuing updated information

    • Coordinating with other terminal controllers as well as enroute and tower controllers

    • Providing alerting services

  • Terminal control areas typically extend from surface up to approximately FL230FL230 (approximately 23,000 ft) and horizontally within a radius of about 3526extmiles3526 ext{ miles} from the busiest airport (regional scope varies by airport).

Departure Control (within Terminal Environment)

  • After IFR clearance for takeoff by a tower controller, the aircraft is instructed to change to the departure controller’s frequency or the adjacent enroute sector if no terminal unit is associated with the airport.

  • Departure control expedites the flow of IFR traffic leaving a terminal control area.

  • Departure control is identified as DEPARTURE on radio.

  • Phraseology example: "VANCOUVER DEPARTURE, THIS IS CATHAY EIGHT-ONE-NINER."

Arrival Control (within Terminal Environment)

  • Arrival controllers expedite IFR traffic inbound to land at an airport within a terminal control area.

  • As the IFR aircraft nears the airport, it is instructed to change to a tower controller’s frequency.

  • Arrival control is identified as ARRIVAL on radio.

  • Phraseology example: "MONTREAL ARRIVAL, THIS IS AEROMEXICO SIX-THREE-SIX."

Combined Arrival-Departure Services

  • When traffic levels are low, arrival and departure control may be combined into a single position.

  • In that case, the position is identified as TERMINAL when communicating on a radio frequency.

  • Phraseology example: "MONTREAL TERMINAL, THIS IS PORTER FOUR-EIGHT-ZERO."

Terminal Surveillance Services

  • Some airports have high traffic volumes with IFR and VFR flights mixed in terminal airspace.

  • Terminal surveillance controllers may handle both arriving and departing IFR and VFR traffic, including transit traffic through the terminal airspace.

  • The procedures for changing frequency for VFR aircraft are similar to IFR procedures:

    • If VFR departures leave the terminal airspace, they are instructed to change to an enroute controller's frequency

    • VFR arrivals landing at the airport are instructed to change to a tower controller’s frequency

  • Terminal surveillance is identified as TERMINAL on radio.

  • Phraseology example: "CALGARY TERMINAL, THIS IS SKYHAWK FOXTROT UNIFORM ZULU ROMEO."

Area Control Services (Enroute)

  • Area control services are provided by enroute controllers to IFR aircraft and some VFR aircraft in specified control areas.

  • Enroute controllers work at Area Control Centres (ACCs).

  • As an IFR aircraft exits the terminal control area, it is instructed to change to the enroute controller’s frequency.

  • The primary role is to separate:

    • IFR from IFR

    • IFR from VFR

    • VFR from VFR (workload permitting)

  • Enroute controllers also provide:

    • Clearances and instructions

    • Arrival information

    • Traffic pass-through

    • Weather information

    • Updated information as received

    • Coordination with other enroute controllers and with terminal and tower controllers

    • Alerting services

  • Communication identifier: the enroute position is identified as CENTRE when communicating on radio frequency, and ACC name is used in radio communications (e.g., TORONTO CENTRE).

  • Phraseology example: "TORONTO CENTRE, THIS IS POLLOT FOUR-FIVE."

IFR Departures and Arrivals (Terminal vs Enroute)

  • Departing IFR aircraft sequence:

    • Tower controller clears for takeoff

    • If terminal control is established, the aircraft is instructed to change to the terminal controller’s frequency

    • On exiting terminal control, the aircraft is instructed to change to the enroute controller’s frequency

    • The aircraft is handed off successively to adjacent sector controls along its planned route until entering the sector serving the destination airport

  • Arriving IFR aircraft sequence:

    • Aircraft approaches the airport and is ready to land

    • If terminal control is established, the aircraft is instructed to change to the terminal controller’s frequency

    • If terminal control is not established, the aircraft changes to the appropriate tower or radio frequency as it approaches the control zone

How Work Is Organized at an Area Control Centre (ACC)

  • ACCs are staffed by both enroute and terminal controllers.

  • Canada is divided into 77 Flight Information Regions (FIRs); each FIR has its own ACC.

  • The seven FIRs are: Vancouver, Edmonton, Winnipeg, Toronto, Montreal, Moncton, and Gander.

  • Airspace controlled by each ACC is divided into specialties, and each specialty into sectors.

  • Sector shapes and dimensions are unique; the base of airspace can range from the surface up to FL600FL600 (about 60,000extftASL60{,}000 ext{ ft ASL}).

Moncton ACC and Its Specialties

  • The Moncton ACC has three specialties: Halifax Terminal, Maritime, and High.

  • Halifax Terminal specialty has a single sector: Halifax Terminal.

  • Maritime specialty is divided into five sectors: Moncton, Charlo, Cape Breton, Digby, and Saint John.

  • High specialty has 25 sectors including Sydney, Taffy, and Natash.

  • Figures illustrate the relationship (specialties and sectors) within the Moncton ACC.

Tracking PVL804: Charlo to Halifax (Provincial Airlines)

  • Example path for Provincial Airlines flight PVL804:

    • Charlo Airport to Moncton Centre (Moncton Centre, Maritime Specialty, Charlo Sector)

    • Progresses to Moncton Centre (Moncton Sector) as it moves south

    • Handover to Halifax Terminal Specialty to begin descent toward Halifax Airport

  • Flight deck dialogue examples:

    • ON DEPARTURE: "ENROUTE CONTROLLER: PROVINCIAL EIGHT-ZERO-FOUR MONCTON CENTRE, IDENTIFIED, CHARLO ALTIMETER TWO-NINER-NINER-ZERO."

    • DURING TRANSITION: "PROVINCIAL EIGHT-ZERO-FOUR MONCTON CENTRE, IDENTIFIED, NINER THOUSAND, DESCEND SEVEN THOUSAND ALTIMETER TWO-NINER-NINER-ZERO."

    • DESCENT INTO HALIFAX: "HALIFAX TERMINAL, THIS IS PROVINCIAL EIGHT-ZERO-FOUR." / Terminal controller: "PROVINCIAL EIGHT-ZERO-FOUR, HALIFAX TERMINAL, RUNWAY ZERO-FIVE, ALT IMETER TWO-NINER-EIGHT-EIGHT, DESCEND SIX THOUSAND."

Wrap-Up

  • The course section reviewed various ATS services and positions, how they function, and the method used to identify positions in radio communications.

  • Key takeaways:

    • Services provided by ATS personnel include information, advisory, control, and alerting services.

    • The objective of control services is safety, order, and efficient traffic flow.

    • Various ATS positions (FSS, FIC, apron advisory, ground, tower, clearance delivery, terminal, enroute/ACC) each have distinct roles and radio identification.

    • Information services at FICs and FSSs are essential for pilot briefings, flight plans, in-flight information, weather, and navigation aid status.

    • Airport operations involve a tiered structure of control: apron, ground, tower, terminal control (departure/arrival/terminal surveillance), and enroute area control.

    • Terminal and area control centres organize airspace into specialties and sectors to manage IFR and VFR traffic, with handoffs between sectors as flights progress.

    • Real-world examples (Charlo to Halifax PVL804) illustrate how aircraft are handed off from one sector/specialty to another within the ACC network.