Communication Theory Flashcards
Notes
- Unless safety will be compromised, pilots shall not change an ATC assigned heading, or alter route without first advising and obtaining a response from the controller.
- Prior to entering an ATZ, you should be in radio contact with the aerodrome ATSU.
ATM Structure:
What are the two main divisions of aerodromes?
- Aerodromes with ATC, where ATC clearances are required to operate on the aerodrome
- Aerodromes with either FIS or A/G, to provide information. There may of course be no radio at all. At FIS, A/G or no-radio aerodromes, you are completely responsible for aerodrome operations and ATC clearances are not required (nor available); however you should advise others of your movements.
The five key R/T positions are:
- Parked Position
- Holding Position
- Downwind
- Final
- Runway Vacated
What are the seven types of Airspace Classes?
The whole reason for the existence of controlled airspace is to protect commercial IFR traffic, by providing an environment within which all traffic and their intentions are known.
Class A Airspace: Allocated to the busiest airspace, e.g. TCA, major upper-level airways, and not available to VFR pilots
Class B Airspace: Not currently allocated in the UK
Class C Airspace: Allocated above FL195 but also below FL195 in certain Control Areas, VFR flights are rarely permitted in Class C Airspaces.
Class D Airspace: Allocated to less-busy controlled airspace; VFR flights are allowed with prior flight notification.
Class E Airspace: Only allocated to some aerodrome in Scotland. Similar to class D airspace, but doesn’t require prior flight notification and within Class E airspace VFR flights are provided with either a Basic or Traffic Service.
Class F Airspace: None currently allocated in the UK.
Class G Airspace: All previously unallocated airspace, uncontrolled and known as the Open FIR (Open Flight Information Region).
Explain what a A/G Radio is at an aerodrome:
An Air/Ground radio station is an information ATSU staffed by a radio operator who has qualified for a CAA certificate of competency to operate on aviation frequencies.
An A/G radio station is designated in radio calls by its name followed by the word Radio and in some cases Traffic.
An A/G radio station operator is not authorised to issue ATC clearance, nor will an A/G radio operator go as far as to say “Take off at your discretion”, as would an aerodrome FISO. However, like FISOs, A/G operators may pass clearances on behalf of other agencies.
AN A/G radio operator can provide:
- Limited Information regarding known traffic, weather and unserviceabilities at the aerodrome.
- Alerting Service
At an aerodrome with an A/G radio station you do not require ATC clearance to operate, nor is there anyone authorised to issue clearance. You should, however:
- Take advantage of the information that the A/G radio station operator can provide; and
- Advise the A/G of your planned movements.
Explain what a Flight Information Service is at an aerodrome:
An Aerodrome Flight Information Service (FIS) is an information ATSU staffed by licensed Flight Information Service Officers (FISOs). FISOs are licensed and regulated by the CAA, though not to the same extent as air traffic controllers.
A Flight Information Service at an aerodrome is designated in radio calls by its name followed by the word Information.
The Main purpose of a FIS is to assist pilots to operate safely and efficiently, in the ATZ surrounding an aerodrome. If you are operating in the ATZ you should be in contact with the relevant ATSU, which in this case will be the FIS.
A FIS is not authorised to issue ATC clearances but may request pilots to make position reports.
A FISO can provide:
- Basic Service
- Alerting Service
At an aerodrome with a FIS instructions are given to aircraft moving on the apron and certain parts of the manoeuvring area. With regard to the runway and in the air, the pilot makes the final decisions, such as how best to join the traffic pattern, when to line up, take off and land.
It is good airmanship to:
- Take advantage of the information the FISO can provide; and
- Advise the FISO of your planned movement.
Explain what an Air Traffic Control Service is at an aerodrome:
An ATC aerodrome is just that. It has an active control tower staffed by highly qualified air traffic controllers, and provides an Air Traffic Control (ATC) service. ATC is, of course, authorised to issue ATC clearances.
Each air traffic controller has completed a demanding CAA course, is licensed, and is closely supervised by the CAA. They may have sophisticated equipment, such as radar, available for their use.
An ATC unit is designated in radio calls by its place name followed by its function. For instance, there are several ATC frequencies at Manchester airport, such as Manchester Ground, Manchester Tower and Manchester Approach. Other ATC units are Director, and Radar.
An ATC unit can provide:
- Air Traffic Control service
- Basic Service
- Alerting Service
Explain what an Area Control Center is:
An ACC can provide:
- Air Traffic Control Service, to aircraft operating in controlled airspace on Airways, and in controlled ATZs.
- Air Traffic Advisory Service, to aircraft flying on Advisory Routes
- FIS & Alerting Service
Explain what an Alerting Service is:
In the event of an accident, they can alert search and rescue (SAR) services if necessary.
Explain what an Advisory Service is:
The objective of the air traffic advisory service is to make information on collision hazards more effective than it would be in the mere provision of flight information service. It may be provided to aircraft conducting Instrument Flight Rules (IFR) flights in advisory airspace or on advisory routes (Class F airspace).
What does LARS stand for and mean?
Lower Airspace Radar Services, when flying in the UK uncontrolled airspace up to and including Flight Level 100 within 30nm of the nominated LARS Units, radar services are available to assist pilots in discharging their collision avoidance responsibilities. The services are either a Deconfliction Service or a Traffic Service.
Explain what a Basic Service is:
The Basic Service allows a pilot maximum autonomy and is an Air Traffic Service provided to give advice and information useful to the safe and efficient conduct of flights.
Flight Rules and Meteorological Conditions - IFR flights in Class G airspace and VFR flights in Class G and E airspace, but may not be appropriate for flights in IMC.
Such items may include:
- Weather Information
- Changes in the serviceability of facilities
- Conditions at aerodromes
- General aerial activity
Explain what a Traffic Service is:
The Traffic Service is a surveillance-based ATS where in addition to a Basic Service, the controller provides specific radar-derived traffic information to assist a pilot in avoiding other traffic.
Flight Rules and Meteorological Conditions - IFR flights in Class G airspace and VFR flights in Class E and G airspace.
Traffic Information - Relevant traffic information will be passed and will be updated if the traffic continues to constitute a definite hazard, or if requested by the pilot.
Deconfliction - Traffic avoidance is ultimately the pilot’s responsibility.
Terrain - The pilot is responsible for terrain clearance.
Headings - Pilots may operate under their own navigation or the controller will provide headings for positioning, sequencing or navigation assistance.
Levels - The pilot may select his own operating levels or he will be provided a level allocation for positioning, sequencing or navigational assistance.
Response to Traffic Information - “Traffic in sight” or “Traffic not sighted”
Explain what a Deconfliction Service is:
The Deconfliction Service is a surveillance-based ATS in addition to the Basic Service. The controller will provide specific radar-derived traffic information and will issue headings and/or levels aimed at achieving planned deconfliction minima against all observed traffic in Class F and G airspace.
The deconfliction minima are: 5nm laterally or 3,000 feet vertically, against unknown or uncoordinated traffic. Between aircraft working the same controller, this may be reduced to 3nm and 1000 feet (some military units may apply 500 feet vertical separation).
CAP 774 stresses that because of controller workload or frequency congestion the ability of a controller to pass deconfliction advice may be reduced or the timeliness of the information affected. Also, a reminder is included of the unpredictable nature of traffic outside controlled airspace and a caveat that achieving the minima is not guaranteed.
Flight Rules and Meteorological Conditions - IFR flights only.
Traffic Information - Traffic Information will be passed together with headings and/or levels aimed at achieving the deconfliction minima.
Deconfliction - Controllers will pass traffic information together with headings and/or levels aimed to achieve the deconfliction minima. Traffic avoidance is ultimately the pilot’s responsibility. Should a pilot elect not to act on instructions, he accepts responsibility for initiating any subsequent collision avoidance against that particular conflicting aircraft.
Terrain - The service is only provided at or above the ATCU’s terrain-safe level. If a pilot requires descent below that level a deconfliction service will no longer be provided - pilots can expect a Traffic Service instead.
Headings - Pilots may operate under their own navigation or the controller will provide headings for positioning, sequencing, navigational assistance or to achieve the deconfliction minima.
Levels - Controllers will normally provide level allocations for positioning, sequencing, navigational assistance or to achieve the deconfliction minima.
