ATCO Flashcards
FIR
London FIR
- LACC
- LTCC
- Military air traffic control
Scottish FIR
- MACC
- ScACC
- OACC
London FIR
LACC - en route traffic in London FIR. Air space over most of England and Wales
LTCC - Handles traffic below 24,500 feet flying to or from londons airports. One of the busiest in Europe borders of France and Netherlands
Military air traffic control - Military controllers provide services to civil and military aircraft operating outside controlled airspace (work closely with civilian controllers to ensure safety)
Scottish FIR
MACC - controls aircraft over much of the north of England, the midlands and north wales. From 2,500 feet up to 28,500 feet
ScACC - controls aircraft over Scotland, NI, N England and N sea from 2,500 up to 66,000 feet
OACC - controls airspace over eastern half of the N Atlantic from the Azores to a boundary with Iceland
What are air-traffic controllers responsible for?
The safe orderly and efficient movement of aircraft from the moment it leaves the departure gate to the aircraft arriving at its gate at its destination
What responsibilities will the role incorporate?
- Preventing collisions between aircraft in the air
- Assisting in preventing collisions between aircraft moving on the apron on the manoeuvering area
- Assisting in preventing collisions between aircraft and obstructions on the manoeuvering area
- Expediting and maintaining an orderly flow of air traffic
What is generated on the ATC computers when a flight plan is filed?
Callsign, route, altitude and speed of the intended flight amongst other details.
Either electronically or paper flight progress strip
What do the controllers use to monitor aircraft progression?
Paper or electronic flight progress strips in conjunction with radar and other displays. Either on the surface of the airport or in the proximity of the airfield or through an en-route sector
What do you controllers and pilots used to communicate?
VHF radio + any information issued by controllers must be read back by pilots
Do ATCOs communicate with each other?
Yes via telephone and computer. ATCOs must pass details of flights as they move from one sector to another.
UK must coordinate with ATCCs in Dublin, Shannon, Brest, Paris, Brussels, Maastricht and Copenhagen. Vice versa
What is an Aerodrome controller?
- Responsible for safety and movement of the aircraft on the airfield from the time it pushes back from stand to departing.
- Will issue instructions for the aircraft to taxi to and from the runway as well as clearances to take off and land
- Tower controllers will also issue routings and clearances to the aircraft prior to departure and ensure the safe movement of all vehicles moving around the airfield
- Busier units may spilt runway specific tasks from movement between the stands and the runway vicinity
What is an Approach controller?
Take over from area controllers as the aircraft is approaching the airport. Give clearance for aircraft to approach and sequence all approaching aircraft for efficient landing
- If using radar will issue headings, altitudes, speeds and other info.
- Spacing of aircraft depends on weather conditions, size of aircraft. Larger aircraft create more wake turbulence than smaller ones so approach controllers must provide correct turbulence wake separation.
What are Approach controllers? x2
At major fields there are holding facilities called ‘Stacks’ which aircraft may be required to enter if delays are expected. Heathrow and Gatwick have four and two stacks respectively
Approach controllers are often based at the airfield which they provide a service for. Although NATS provide the approach function for London airports from swanwick
When the aircraft is established on the final approach between 6-12 miles from the runway, aerodrome controllers will take over
What is an Area controller?
Responsible for the aircraft in the climb, descent and en-route phase of the flight.
Will issue levels, headings and speeds to separate aircraft to provide the most safe and expeditious routing to the exit point.
Agreement with next sector/controller along the entire route of the aircraft is a major function of the role and each aircraft will be transferred along the line according to set conditions every time it leaves and enters a new sector.
Two main categories of airspace
Controlled airspace
Uncontrolled airspace
What does controlled airspace involve?
Classes A,C,D,E
Class A
A - only IFR (instrument flight rules) is permitted. Most strictly regulated airspace where pilots must comply with ATC instructions at all times. Mainly airlines and business jets
Class C
C - Flight level (FL) 195 to FL 660. Both IFR and visual flight rules (VFR) traffic operates and requires clearance to enter, compliance with ATC mandatory
Class D
D - IFR and VFR use, ATC clearance is needed and compliance is mandatory, Control areas around aerodromes are class D and in the class D airspace a speed limit of 250 knots applies if the aircraft is below FL 100
Class E
E - IFR AND VFR use. IFR traffic requires ATC clearance and compliance with ATC instruction is mandatory for separation purposes. VFR traffic does not require a clearance to enter class E airspace
What is controlled airspace also divided by?
Divided by type, depending on where it is and the function it provides.
Aerodrome control zones
Afford protection to aircraft within the immediate vicinity of Aerodrome
Control areas
Situated above Aerodrome traffic zone (ATZ) and afford protection over a larger area to a specific upper limit
Terminal control areas
Normally established at the junctions of airways in the vicinity of one or more major Aerodromes
The London terminal control area
Example of terminal control area and deals with air traffic arriving and departing from London Heathrow, Gatwick, Luton, Stansted, London City, Northolt, Biggin Hill, Southend, Farnborough, and other minor airfields in the London area
What are Airways?
Airways are corridors of airspace connecting the Terminal control areas and link up with airways in other countries too.
Airways are normally 10 miles wide and have bases between 5000 feet and 7000 feet and the extend upward to a height of 24,500 feet.
Upper air routes (UARs) sit above airways. Their vertical limits are usually FL 250 FL 460. Civil and military aircraft operating above FL245 are subject to a full and mandatory Air Traffic Control Service
What is Uncontrolled airspace?
Within Class G airspace, aircraft can fly when and where they like. Subject to simple rules. Many pilots notify ATC of their presence and intentions and pilots take full responsibility for their own safety, although they can ask for help.
Services are available to pilot
Deconfliction service
Traffic service
Basic service
Services provided by ATC for pilots
Deconfliction service
Traffic service
Basic service
Alerting service - notify appropriate organisations regarding aircraft in need of S&R
Procedural service - non radar based service in which deconfliction advice is provided against other aircraft receiving a procedural service from the same controller.
Air traffic control over the Atlantic.
Shanwick Oceanic control area (based at prestwick) has shared responsibility. UK, PORTUGAL, the USA, CANADA, ICELAND.
Where is NATS responsible for? (Atlantic)
Responsible for the eastern portion of the Atlantic which stretches between latitudes 45 degrees north and 61 degrees North and westward to longitude 30 degrees west. Voice communication is maintained through HF (High frequency) radio, based in Shannon.
A pilot makes position reports usually every 10 degrees of longitude.
OACC and Atlantic
Relevant OACC construct a system of organised tracks every 12 hours to accommodate as many aircraft as possible on their most economic flight path.
Prestwick OACC is responsible for the westbound track system and Gander OACC, Canada for the eastbound track system
Prevailing wind is taken into account as airlines like to take advantage of a tailwind, which is more fuel economical and decreases travel time
Oceanic control track and separations
60 nautical miles between aircraft at the same level
10 minutes between aircraft at the same level on the same track
Aircraft separated by 1000 feet vertically in RVSM airspace
Separation
In controlled airspace, aircraft are separated by internationally agreed standards.
In the London terminal control area aircraft operating under radio control must be separated by three nautical miles from other aircraft the same had a lesson 3 miles apart they must be separated by minimum of 1000 feet
Separation 2
Outside of London terminal co troll airspace, aircraft operating under radar control must keep 5 nautical miles apart if they are at the same level or 1000ft vertically up to FL20. Above this vertical separation may continue to be provided up to FL410, subject to reduced vertical separation minima (RVSM) rules. Otherwise 2000fy should be applied
RVSM
NATS was at the forefront of introducing reduced vertical separation minima (RVSM)
Aircraft which have had their altimeters checked to a high degree of accuracy are allowed to fly across the Atlantic track structure with only 1000ft separation above FL290 and below FL410
IFACTS
Interim future area control tools support; became operational in 2012, helping NATS meet the projected demand of 3 million annual movements at Swanwick by 2015
IFACTS objectives
Increase capacity
Eliminate paper flight progress strips
Reduce the number of safety significant events
IFACTS Aims
To reduce the controllers workload by equipping them with tools to aid them in medium term confliction resolution
Tactical clearances
Trajectory prediction will also assist controllers by calculating where the aircraft will be in 18 minutes based on the aircrafts level, speed and heading
Controller can input any tactical clearances have the use of a separation monitor which helps monitor the traffic in their sector and displays interactions that are predicted to happen within the sector in the next few minutes
Tactical what if
IFACTS also allows the controller to check what might happen if a particular clearance were to be issued to an aircraft. Will superimpose on the radar screen the projected trajectories of the aircraft involved
Mode S
Mode S is an improvement on the current mode A and C
Provided the controller with the opportunity to view certain information, e.g. Selected flight level/indicated air speed/heading etc. Which the pilots have in the cockpit to aid with conformance monitoring and reducing RT for both controller and pilot
Time based Separation
2015 NATS was the first to introduce TBS on final approach, being initially deployed at Heathrow
Instead of distance between planes time was used.
The stronger the wind is, the quicker the vortex that is produced will be dispersed.
As wind speed increases the closer the aircraft can be positioned in trail on final approached therefore increasing the available landing rate
SESAR
Single European Sky ATM Research
European wide concept that aims to deliver a restructuring of airspace as a function of flows not borders to allow more direct routing for aircraft and closer intervention between ANSPs
This is to enable dynamic airspace management and a more efficient AT Management capability, ultimately creating additional capacity
Radar
The use of radar, both primary and secondary assists ATCOs in their main task of ensuring safe separation between aircraft
Primary radar
Basic information about position of aircraft in relation to the radar
Will show aircraft within its coverage, high terrain, certain weather and possibly large flocks of birds
Secondary radar
Selective and displays information from aircraft equipped with a transponder.
Aircraft are given a four digit code which displays the callsign, and height information to the CO
Navigational aids
VHF Omnidirectional range (VOR) which emits radial signals which aircraft can fly along.
There are 360 radials aircraft can fly toward or away from a VOR. Each radial represents 1 degree from 0-359 degrees
Non directional beacon or VOR
NDB emits a signal which pilots can fly toward. 25 nautical miles is the usual range where as a VOR has a much greater range of 125 nautical miles
Flight management systems
They can vary in complexity from the basic heading and altitude to the systems which can control the aircraft from departure to arrival
Approach controllers issue instructions to enable the aircraft to intercept the ILS ( instrument landing system). The ILS is a ground based radio guidance system which transmits two directional radio beams, the localiser and the glide path. Usual descent path for ILS is 3 degrees
