The document discusses air traffic control and services. It aims to prevent collisions between aircraft during flight and on the ground through separating aircraft laterally and longitudinally based on distance and time. It describes control areas like aerodromes and traffic zones. It also discusses flight level assignment, area navigation systems, routes and waypoints to guide aircraft along planned paths.

1. AIRTRAFFIC SERVICES
UNIT 2
DINESHBABU V/AP/NIET

2. PURPOSE OF AIRTRAFFIC
CONTROL
• Preventing collision between aircrafts during
flight
• Preventing collision between aircrafts during
surface movement in the maneuvering area.
• Guide the aircrafts to fly clear-off all
abstractions
• Schedule the flights to maintain an orderly
flow of air traffic ,safe and efficient operation.
DINESHBABU V/AP/NIET

3. CONTROLAREAS
• Aerodrome A defines area on land or water are
used either wholly or partially for the arrival ,
departure and surface movement of aircraft
• Aerodrome Traffic Zone (ATZ)-Airspace of
defines dimensions established around an
aerodrome for the protection of aerodrome traffic
• Aerodrome Traffic all traffic in the maneuvering
area of an aerodrome and all aircraft flying in the
vicinity of an aerodrome
DINESHBABU V/AP/NIET

4. OBJECTIVE OF ATS
• Prevent collision between aircrafts during flight
operation irrespective of the airspace
• Prevent collision between aircrafts during ground
maneuvering in the aerodrome operating area.
• Give guidance to pilot to maintain separation
from obstacles.
• Manage the flight schedules and expedite an
orderly flow of aircraft.
• Provide advice and information useful for the safe
and efficient conduct of flights
DINESHBABU V/AP/NIET

5. DIFFERENT PARTS OF AIRTRAFFIC
SERVICES
• Area control services
• Approach control services
• Aerodrome control services
• Air traffic advisory services
• Flight information services
• Alerting Services
DINESHBABU V/AP/NIET

6. Assignment of cruising levels
/minimum flight altitude
• Minimum altitude is assigned to each aircraft
in ATC routes to ensure at least 1000 ft vertical
clearance above the height obstacle within
18km on each side of center line of route.
• Pilot should fly a/c in accordance with the
route specified by ATC. Deviation in this pilot
should get clearance from ATC –below lower
altitude cruising level is not permitted
DINESHBABU V/AP/NIET

7. Assignment of cruising levels
/minimum flight altitude
DINESHBABU V/AP/NIET

8. Guidance for selection of flight level
• Flight levels are specified in flight plans
– Above transition altitude in terms of flight level
– Below transition altitude in terms of altitude
• Minimum flight altitude:
– the aircraft should not decent below minimum safe enroute altitude
except
• Initial approach of aircraft in the aerodrome and position of a/c positively
established by reference to radio /ATS radar
• System of cruising level
– All VFR flights fly above 3000ft from the ground or water
– All IFR flights should fly as specified in the Chart and flight plan
– During approach ,pilot should follow ATC specified level (curing level
is not applicable )
– The flights which flies above FL150 (15000ft) ,should be conducted as
IFR flights
DINESHBABU V/AP/NIET

9. ATC routes and significant points
• It is designed by different numbers ,codes, alphabets for
easy of identification of pilots and ATC
– Easy reference (without geological coordinates)
– Related to specific structure of airspace
– Required level of navigation performance accuracy
– Indicate route is used for specific type of aircraft
• Requirements
– It should be in simple and unique manner
– Used by both ground and airborne automation system
– Should be brief by operationa
DINESHBABU V/AP/NIET

10. Area navigation system (RNAV)
• It is the method of IFR navigation that allows an
aircraft to choose any course within a network of
navigation beacons ,rather than navigate directly to and
from beacons.
• Area navigation used to be called "random
navigation“(RNAV)
• RNAV can be defined as the method of navigation that
permits aircraft operation on any desired course within
the coverage of station referenced navigation signal or
within the limits of a self contained system capability
or a combination of these.
DINESHBABU V/AP/NIET

11. Working of RNAV system
• It consists of
– VOR & DME equipments to receive signals from
VOR/DME stations for landing Surfaces .For oceanic
operations, Inertial Navigation System (INS) were used .
– Computers for processing
– CDI (course direction indicators & HSI ( Horizontal
situation Indicators ) to guide the pilot along his planned
route in two dimensions.
• The computer reproduce the aircrafts performance
parameters.
• They collect the ideal vertical flight paths for climb and
decent to arrive over places at particular altitude
DINESHBABU V/AP/NIET

12. FMS
• FMS (Flight Management System )- Auto pilot
system-Fourth Dimension can also controlled by
FMS
– The crew select a series of waypoints which are
planned or turning points
– Theses points can be defined from one or more pairs of
VOR or DME stations.
– The computer then calculates and displays directions
on the CDI or HIS to pilot to keep the aircraft on the
track between the last way points and the next
DINESHBABU V/AP/NIET

13. RNP
• RNAV is now one of the navigation techniques of
performance based navigation PBN; Required
navigation performance (RNP) is used.
• RNP is a type of PNB that allows an aircraft to fly
a specific path between two 3D defines points in
Space.
• A navigation specification that includes a
requirement for on-board navigation performance
monitoring and alerting is referred to as an RNP
specification-Not this called RNAV
DINESHBABU V/AP/NIET

14. Separation with respect to distance
and time
• Vertical Separation Minimum
A nominal 1000 feet below FL290 and a
nominal 2000 feet at or above FL290
A nominal 1000 feet when both aircraft are
RVSM compliant and operating within
designated RVSM airspace.
DINESHBABU V/AP/NIET

15. • C limb and descent
An aircraft may be cleared to a level previously occupied by another
aircraft after the latter has reported vacating it, except when:
– Severe turbulence is known to exist; or
– The aircraft concerned are established at the same holding pattern; or
– The difference in aircraft performance is such that less than the applicable
separation minimum may result; in which case such clearance shall be
withheld until the aircraft vacating the level has reported at or passing
another level separated by the required minimum.
• Pilot in direct communication with each other may, with their
concurrence, be cleared to maintain a specified vertical separation betwee
• Step climb and descents
The step climb / descent procedure may be used for simultaneous climb /
descent of the aircraft to vertically separated levels provided that the
lower / higher aircraft is progressively assigned levels that provide vertical
separation with the higher / lower aircraft. n their aircraft during ascent or
descent.
DINESHBABU V/AP/NIET

16. VMC (visual metrological condition )
climb and decent
• When so requested by an aircraft and provided it is agreed by the
pilot of the other aircraft, an ATC unit may clear controlled flight,
including departing and arriving flights, operating in airspace
Classes D and E in VMC during the hours of daylight to fly subject to
maintaining own separation to one other aircraft and remaining in
VMC. When a controlled flight is so cleared, the following shall
apply:
a) Clearances shall be for a specified portion of the flight at or
below 10,000 feet, during climb and descent;
b) Essential traffic information shall be passed; and
c) If there is possibility that flight under VMC may become
impracticable, an IFR flight shall be provided with alternative
instructions to be complied with in the event that in VMC cannot be
maintained for the term of clearance.
DINESHBABU V/AP/NIET

17. Horizontal separation
• The three types of horizontal separation are:
a) Lateral separation;
b) Longitudinal separation;
c) Radar separation.
• Lateral separation
When the aircrafts are over different
geographic locations as determined visually or
by reference to a navigation aids
.
DINESHBABU V/AP/NIET

18. Lateral separation –same navigation
aids
• VOR
Both aircraft are established on radials
diverging by at least 15 degrees and at least
one aircraft is 15 NM or more from the facility.
DINESHBABU V/AP/NIET

19. Lateral separation –same navigation
aids
• NDB
Both aircraft are established on tracks to or from
the NDB, which are diverging by at least 30
degrees and at least one aircraft is 15 NM or more
from the facility.
DINESHBABU V/AP/NIET

20. Lateral separation –same navigation
aids
• DR (dead reckoning)
Both aircraft are established on tracks diverging by at
least 45 degrees and at least one aircraft is 15 NM or
more from the point of intersection of the tracks, this
point being determined either visually or by reference
to a navigational aid and both aircraft are established
outbound from the intersection
DINESHBABU V/AP/NIET

21. Longitudinal separation
• For the purpose of application of longitudinal
separation, the terms same track, reciprocal tracks
and crossing tracks shall have the following
meanings:
• a) Same track: same direction tracks and
intersecting tracks or portions thereof, the angular
difference of which is less than 45 degrees or more
than 315 degrees, and whose protection areas
overlap
DINESHBABU V/AP/NIET

22. • Reciprocal tracks
Opposite tracks and intersecting tracks or portions
thereof, the angular difference of which is more
than 135 degrees but less than 225 degrees, and
whose protection areas overlap.
DINESHBABU V/AP/NIET

23. • Crossing Tracks
Intersecting tracks or portions thereof other than
those specified in a) and b) above.
DINESHBABU V/AP/NIET

24. Longitudinal separation minima
based on time
Aircraft at the same cruising
level
DINESHBABU V/AP/NIET

25. Longitudinal separation minima
based on time
• 10 minutes, if navigation aids permit frequent
determination of position and speed
• 5minutes separation is maintained in some special cases
• 3mins separation is maintained if the preceding aircraft is
maintained true airspeed faster than succeeding aircraft by
74kmph (40NM)
DINESHBABU V/AP/NIET

26. DINESHBABU V/AP/NIET

27. Aircraft climbing or descending
• Traffic on the same track
• 15 minute separation
DINESHBABU V/AP/NIET

28. 10 minute separation
DINESHBABU V/AP/NIET

29. 5 minute separation
DINESHBABU V/AP/NIET

30. DINESHBABU V/AP/NIET

31. DINESHBABU V/AP/NIET

32. Reciprocal track
DINESHBABU V/AP/NIET

33. ATC CLEARANCES
• PURPOSE
– Efficient flow of airtraffic
– Prevent collision /accident by scheduling the
flights in maneuvering area.
– Issue of flight plans and routes
– Information related to clearance is transmitted to
pilot in advance for compliance within a time
framework
DINESHBABU V/AP/NIET

34. CONTENTS OF ATC
• ATC clearance contains
– Flight plan
– Clearance limit
– Route of flight
– Flight levels and change of levels
– Departing aircraft
• After clearance from departing aerodrome –information is passed to
ATC unit and destination aerodrome
– En-route aircraft
• After clearance issued by departing a/c-adjacent ATC unit for clear
for specified point for specific period
• ATC clearance unit should give clearance whenever it is necessary
DINESHBABU V/AP/NIET

35. Clearance limit
• Significant point in controlled airspace or
aerodrome
• Limit can be extended to destination
aerodrome –a/c is report to each reporting
points
• In Intermediated stops, a/c must get assured
clearance from that ATS and ATC units
• If a/c is in uncontrolled airspace ,limit
boundary is up to controlled airspace
DINESHBABU V/AP/NIET

36. Clearance for flight route and Levels
• Route of flight
– Routes of clearances are specified in flight plan
– When a/c is following standard routes this clearance is specified as
„cleared via departure‟ and „cleared via arrival‟ is used
– Mostly all a/c offered direct route unless traffic density arises
• Levels
– Place or time for climb/decent is also intimated whenever required
– Instructions for dept and arrival levels is given to pilot
– If particular level is effected then subsequent level is intimated to pilot
– Clearance related to particular change in level
DINESHBABU V/AP/NIET

37. Clearance of request for change in
flight plan
• Whenever the traffic condition does not permit for
request of change the word “UNABLE” is used.
• Whenever the alternate flight plan or flight level is
intimated to pilot ,the details of procedure which
includes
– New route /level
– Time and point at which it rejoin previous route
DINESHBABU V/AP/NIET

38. Read back of clearance
• The flight crew must read back the ATC clearance
instructions to ATC by voice.
• The information includes
– ATC route clearance
– Clearance and instruction to enter , land, take off, to held
,cross ,taxi ,back track on any runway
• All clearance issued by ATC should be acknowledged
by flight crew
• Take immediate actions to correct any discrepancies
revealed by read back
• Communication is read back to flight crew is
transmitted separately.
DINESHBABU V/AP/NIET

39. FLIGHT PLAN
• Before any flight is undertaken ,the details of
flight is given by ATS unit
• Complete or portion of flight detail is in the
form of ICOA model flight plan
• A Flight plan shall be submitted to the ATS
reporting office during flight and it is
transmitted to ATC unit on Air ground control
frequency
DINESHBABU V/AP/NIET

40. • Flight plan is given for
– Scheduled flights
– Non-scheduled flights
– Local/training flights
DINESHBABU V/AP/NIET

41. SCHEDULED FLIGHTS
• The flight plan for scheduled flights should be
in printed form ATS authority through
electronic media
• The operations are recoded and saved for six
months .The operation of ATS ,COMM,MET
briefing and data/documents are included.
• The pilot or crew in person should report to
ATC officer when special weather condition or
other aspect which affect the safety of flight.
DINESHBABU V/AP/NIET

42. Unscheduled flights
• The flight plan should by duly signed and
submitted by pilot at the time of depart to the
ATS unit /aerodrome
• If any operator (regular air
transport/authorized agency ) ,the flight plan is
duly signed by state of registry .
• In above case the flight departure is authorized
to obtain ATS units,CMM and MET briefing
DINESHBABU V/AP/NIET

43. Local/training flight
• As same as before
• For training flights conducted by flying clubs within the
aerodrome traffic zone –flight plan is submitted in
telephone
– Information are a/c identification
– Flight rule (IFR/VFR)
– Name of pilot/trainees
– No.of.person onboard
– Duration of flight
– Endurance
• Flights conducted cross country (away from aerodrome) –
ATS not exists-the reporting is given to FIC on phone
DINESHBABU V/AP/NIET

44. Submission of flight plan
• All flight plan shall be submitted prior to operation
– Provided by ATC (complete/portion )
– Any IFR within advisory
– Flights within destination or along that route ,ATS is required to
facilitate the services for flight information ,alerting , search and
rescue
– Need Military operation
– Across the international borders.
• Flight plan is submitted before depart to ATS officer ,during
flight to the Air ground control radio station.
• Flight shall be submitted sixty minutes before depart.
• If submitted during flight ,it should reach apporpriate ATS
unit at least before 10 mins (crossing /entry to that control
area )
DINESHBABU V/AP/NIET

45. Completion of flight plan
• The flight plan should comprise all the information as required by the
appropriate ATS units
• It should contains
– a/c identification ,flight number
– Flight level
– Route
– Destination /intermediate stops
– Flight duration ,endurance
– Duration in controlled /uncontrolled air spaces
– Type of fight (IFR/VFR)
– Communication type
– No of persons on board
– Flight crews ,attendants other necessary information
• Flight plan should be complete and signed by pilot in command (copy is
retained )
DINESHBABU V/AP/NIET

46. Closing of a flight plan
• Arrival report
– Report of arrival ,after landing shall be made in person by
radio/telephone(ATS units where we submitted flight plan )
– If there is no airtraffic unit is exists at arrival, report is submitted
to nearest ATS unit (quick)
– if there is inadequate communication facility at the arrival
,alternate arrangement is not in ground-report is given to flight
information services
• Arrival report contains
– a/c identification
– Departure/destination aerodrome
– Arrival of aerodrome
– Time of arrival
DINESHBABU V/AP/NIET