1. Airmanship Knowledge Learning Outcome 1 Air Traffic Control
Uncontrolled copy not subject to amendment
Airmanship Knowledge Learning Outcome 1 Air Traffic Control
Revision 1.00

2. Airmanship Knowledge Learning Outcome 1 Understand the types of airfield operations used for the control of aircraft

3. Contents Control Towers Controllers Communication Systems
Visual Communications
RADAR
Approach Aids

4. Air Traffic Control

5. Introduction
On RAF Airfields all movements of aircraft, both on the ground and in the air are monitored by Air Traffic Control (ATC)

6. The Control Tower
Is always in a prominent position in the aircraft manoeuvring area
Houses electronic & radio equipment and may also have a Bird Control Unit

7. The size & design of ATC Towers varies considerably.
The Control Tower
The size & design of ATC Towers varies considerably.

8. Aerodrome Controller Is in charge of movements: On the Ground
In the Air
Sometimes Called:
Airfield Controller
Local Controller
Movements include:
Aircraft
Vehicles
Pedestrians
Is also in charge of aircraft in the circuit, They always work in the control room, with their big glass windows, so they have uninterrupted views of the airfield.
On large airfields this is split in two as there is too much work for one person.
Aircraft movements on the ground up to the runway are controlled by
a controller called Ground.
Aircraft movements on the runway and in the local area are controlled
by a controller called Tower.

9. Approach Controller On light usage airfields On heavy usage airfields
The departures are separated
out under the Departures
Controller
They control aircraft:
departing the airfield
making instrument approaches
Both use RADAR displays, RT and landline communications
1. Controls aircraft departing the airfield circuit and those making instrument approaches.
2. May sometimes provide radar service to aircraft in transit through the area of responsibility of the airfield.
3. As most of the aircraft are out of sight of the field the approach controller does not need a window.
4. Instead he obtains information from RT , landline communications, and Radar displays

10. Runway Controller
For more effective control a Runway Controller may be used:
At small airfields with lots of take-offs and landings
They are in direct contact with Aerodrome/Local Controller
Caravan is painted in red and white squares, positioned to the left of the touch-down end of the runway in use.

11. Runway Controller
The Runway controller can refuse aircraft permission to move onto the runway, land or take-off in some circumstances

12. Runway Controller For example they might:
Prevent an aircraft from landing with its undercarriage retracted by firing a RED flare.
Stop an aircraft from taking-off which had for example a panel unlocked or a fuel leak, by showing a steady RED on the signalling lamp.

13. Runway Controller
Warn vehicles or aircraft on the ground to move clear of the landing area, by showing RED flashes on the signalling lamp.
Give permission to take-off, with a steady GREEN on the signalling lamp.

14. Communication Systems
Good Communications are essential to Air Traffic Control

15. Communication Systems
Swift and accurate contact is achieved through the use of:
Special Telephones
Tele-Talk Systems
Radio Telephony (RT) (Ground To Air)
Uses VHF and UHF to talk to aircraft and vehicles.
These frequencies provide clear lines of communications.
Each airfield and its section have their own frequencies.

16. Visual Communications
Stationary Object Hazard
Bad Ground Markers
0.61 metres
square

17. Visual Communications
Helicopter Operating Areas:
The ‘H’ is 4 metres high by 2 metres across
It may also have a box around the ‘H’.
Well clear of fixed wing aircraft OR

18. Radar
Stands For:
RAdio
Detection
And
Ranging

19. Radar Consists of a Transmitter and a Receiver
A short pulse energy is transmitted from an aerial and the receiver “listens” for an echo.

20. Radar
The receiver detects which reflections are from aircraft, and it can determine their position, direction of travel and speed.
This information is then displayed through a cathode ray tube onto a screen. In this way radar has become the “eyes” of air traffic control

21. Radar Aids
The two main radar aids likely to be seen at Royal Air Force airfields are:
Surveillance Radar
Precision Approach Radar (PAR)

22. Surveillance Radar
Is used both to monitor air traffic passing through an area and as an airfield approach aid.

23. Surveillance Radar
Enables the controller to locate the aircraft and direct it to a position and height near the airfield

24. Surveillance Radar Can be used for an airfield approach:
Surveillance Radar Approach (SRA)
The pilot hears directions to put him on the runway centre
line and also heights that he should be passing every mile i.e.
“On runway centre line at 5 miles, should be passing
1850Ft”

25. Precision Approach Radar
The controller has two screens, one for the aircraft’s elevation (height) and one for azimuth (left and right), relating to the approach path

26. Precision Approach Radar
The controller passes instructions by RT to the pilot to guide the aircraft down the correct glideslope and
centreline towards the touch-down point
The procedure is called a Ground Controlled Approach (GCA) or PAR Approach.
The pilot hears directions to put him on the runway centre
line and the ideal glidepath i.e.
“Left of centre line, come right 2 degrees, slightly low
on glidepath, not correcting”

27. Precision Approach Radar

28. Precision Approach Radar
PAR 2000 Radar

29. Radio Aids
The two main Radio Aids likely to be seen at Royal Air Force airfields are:
Digital Resolution Direction Finding (DRDF)
Instrument Landing System (ILS)

30. DRDF
It is a common airfield approach aid at small airfields but is seldom used at large busy airfields
It receives a carrier wave only transmission (no speech) from an aircraft and displays it on a CRT as a green line called a “trace”.
Enables the approach controller to tell the pilot what course to fly to the vicinity of the airfield for a visual approach
Controllers can direct the aircraft to a point above the airfield and from there control its descent through cloud (CDTC) to a height and position on the approach from which the pilot can either land visually or employ a runway approach aid.

31. Instrument Landing System
ILS is a runway approach aid:
Fixed transmitters on the ground send out a special pattern of radio signals
These define a radio beam that is like a pathway in the sky
The pathway then leads to the touch-down point on the runway

32. Instrument Landing System
Glidepath
ILS transmits 2 frequencies
90Hz signal is strongest, so aircraft is above the Glidepath
Localizer
Transmitter
Glidepath
Runway
90Hz
150Hz

33. Instrument Landing System
Glidepath
ILS transmits 2 frequencies
150Hz signal is strongest, so aircraft is below the Glidepath
Localizer
Transmitter
Glidepath
Runway
90Hz
150Hz

34. Instrument Landing System
Glidepath
ILS transmits 2 frequencies
Both signals are equal, so aircraft is on the Glidepath
Localizer
Transmitter
Glidepath
Runway
90Hz
150Hz

35. Instrument Landing System
Localizer
ILS transmits 2 frequencies
90Hz signal is strongest, so aircraft is right of the Localizer
Localizer
Transmitter
Glideslope
Runway
Runway Centre Line
90Hz
150Hz

36. Instrument Landing System
Localizer
ILS transmits 2 frequencies
150Hz signal is strongest, so aircraft is left of the Localizer
Localizer
Transmitter
Glideslope
Runway
Runway Centre Line
90Hz
150Hz

37. Instrument Landing System
Localizer
ILS transmits 2 frequencies
Both signals are equal, so aircraft is on the Localizer
Localizer
Transmitter
Glideslope
Runway
Runway Centre Line
90Hz
150Hz

38. 90Hz 150Hz 90Hz 150Hz Localizer Transmitter Glidepath Runway Localizer
Glideslope
Runway
Runway Centre Line
90Hz
150Hz

39. GPS Approach Some airfields have been approved for GPS Approaches
as long as the aircraft equipment has been approved.
The GPS Approach is flown on the same instruments as
an ILS Approach and gives the same indications.

40. Questions?

41. QUESTION
WHICH BUILDING ON AN AIRFIELD HOUSES THE PEOPLE
THAT MONITOR AIRCRAFT ON THE GROUND AND IN THE AIR?
A. AIR TRAFFIC CO-ORDINATION ROOM
B. AIRBORNE TRAFFIC CONTROL ROOM
C. AIR TRAFFIC CONTROL TOWER
C. AIR TRAFFIC CONTROL TOWER
D. AIR TRAFFIC CO-ORDINATION TOWER

42. QUESTION
WHICH OF THE FOLLOWING WOULD NORMALLY WORK IN
A GLASS WALLED ROOM IN A CONTROL TOWER
A. PAR CONTROLLER
B. AIR CONTROLLER
C. APPROACH CONTROLLER
D. AIRFIELD CONTROLLER
D. AIRFIELD CONTROLLER

43. QUESTION
HOW DOES AN APPROACH CONTROLLER RECEIVE
INFORMATION ABOUT AN AIRCRAFT
A. RT, LANDLINE COMMUNICATIONS AND RADAR
A. RT, LANDLINE COMMUNICATIONS AND RADAR
B. RADAR ONLY
C. RT ONLY
D. RT AND LANDLINE COMMUNICATIONS

44. QUESTION
WHAT COLOURED SIGNAL WOULD BE USED BY A RUNWAY
CONTROLLER TO CLEAR AN AIRCRAFT FOR TAKE-OFF ?
A. A STEADY RED
B. A FLASHING GREEN
C. A FLASHING RED
D. A STEADY GREEN
D. A STEADY GREEN

45. QUESTION
HOW DOES THE CONTROLLER PASS PAR INSTRUCTIONS
TO THE PILOT ?
A. RT
A. RT
B. RADAR
C. MORSE CODE
D. RF BEAM

46. QUESTION
WHERE DOES THE PAR ALLOW THE PILOT TO GUIDE
THE AIRCRAFT TO ?
A. TO THE DESIGNATED DISPERSAL AREA
B. TO THE CORRECT GLIDESLOPE AND CENTRELINE
B. TO THE CORRECT GLIDESLOPE AND CENTRELINE
C. TO AN AIRWAY IN CONTROLLED AIRSPACE
D. TO THE TAKE-OFF POINT

47. QUESTION
DRDF IS USED TO ?
A. DIRECT AN AIRCRAFT WHILE TAXYING
B. DIRECT AN AIRCRAFT AFTER TAKE-OFF
C. DIRECT AN AIRCRAFT TO THE VICINITY OF THE AIRFIELD FOR A VISUAL APPROACH
C. DIRECT AN AIRCRAFT TO THE VICINITY OF THE AIRFIELD FOR A VISUAL APPROACH
D. DIRECT AN AIRCRAFT TO THE RUNWAY TOUCHDOWN POINT

48. QUESTION
AN ILS APPROACH IS USED TO ?
A. TALK AN AIRCRAFT ONTO THE CORRECT GLIDEPATH AND CENTRELINE
B. FOLLOW ELECTRONIC SIGNALS ONTO THE CORRECT GLIDEPATH AND CENTRELINE
B. FOLLOW ELECTRONIC SIGNALS ONTO THE CORRECT GLIDEPATH AND CENTRELINE
C. APPROACH THE AIRFIELD FOR A VISUAL APPROACH
D. DEPART THE AIRFIELD

49. QUESTION
A GPS APPROACH IS DISPLAYED ON THE SAME INSTRUMENTS AS ?
A. A PAR
B. A DRDF
C. AN ILS
C. AN ILS
D. AN SAR