� What is ATC?
air-traffic control
� Definitions (noun)
� an organization that facilitates the safe and orderly movement of aircraft within and between airports.
What is an ATC service?
� An ATC service is provided according to the particular circumstances and class of airspace, for the purpose of:
� preventing collisions between aircraft in the air;
� assisting in preventing collisions between aircraft moving on the apron and the manoeuvring area;
� assisting in preventing collisions between aircraft and obstructions on the manoeuvring area;
� expediting and maintaining an orderly flow of air traffic.
Mats part 1
How do we do it?
V 10
London & Scottish FIRs:
1m km2 – 11% of Europe’s
airspace and 25% of
traffic
Shanwick
2.2m km2 – 80% of North
Atlantic traffic
Our airspace…Flight Information Regions
NATS Private V 10
Prestwick CentreHandles on average 2,700 flights/day
Swanwick CentreHandles on average 6,000 flights/day
– Scottish Oceanic Control Centre– Scottish Area Control Centre
– London Area Control Centre– London Terminal Control Centre
– London Military Air Traffic Control
1.1m movements FY 15/16
1.8m movements FY 15/16
Our Centres
1650 controllers
SEPARATION
WHAT DO WE DO WHEN WE HAVE
MORE THAN ONE PLANE IN THE AIR?
(THIS IS OFTEN THE CASE)
� We need methods to keep
them apart.
� Do not fear… these have
been developed and are
used to great effect
everyday!
� What are the two ways we
make them miss?
1. Vertically
2. Horizontally
Separations
Vertical Separation:
1000ft
Horizontal separation:
5nm for upper airspace
3nm for lower airspace
LATERAL SEPARATION
Longitudinal Separation
FL350
300kts-FL350
300kts
10 miles
Areas of responsibility
To control airspace from
Lands End to John O’Groats
and from 0ft to 66 000ft
would be very difficult.
• Swanwick alone can work thousands of flights per
hour. Would one person
have the time to speak to
that many planes?
• So what do we do?
• We split the airspace up into smaller chunks called sectors
RADAR
Radio Direction And Range
PrimarySecondary Surveillance RADAR Co-Located SSR and Primary
How to tell them all apart
Primary Only Primary and
Secondary
with Mode C
Primary and
Secondary
with Code
Call Sign
Conversion
and Mode S
Primary and
Secondary
RADAR returns
Aircraft Use;
On departure they fly on a SID (Standard Instrument Departure) to
defined waypoint or NAVaid or an RNAV SID
En-route use Navigation aids to fly airways or RNAV routes
On arrival they use a STAR (Standard Terminal Arrival Route)
NDB
NON – Directional Beacon
NDB is a ground-based, low
frequency radio transmitter
• Using an automatic direction finder (ADF),
a standard instrument
on board an aircraft a
pilot can tune into a
Non directional
beacon. When tuned
in we have a direction
to the beacon relative
to the aircraft (provides
bearing information
only).
Bearing 340 degrees
NAVaids
VOR
VHF OMNI DIRECTIONAL RADIO
RANGE
(VOR) IS A SHORT-RANGE RADIO
NAVIGATION SYSTEM FOR AIRCRAFT.
� Like an NDB, the navigation
signal allows the airborne
receiving equipment to
determine a bearing from
the station to the aircraft
but also informs the pilot
which radial the aircraft is
sitting on.
250 degree radial
Bearing 070 degrees
VOR
DME
DISTANCE MEASURING
EQUIPMENT
AIRCRAFT USE DME TO
DETERMINE THEIR DISTANCE
FROM A LAND-BASED
TRANSPONDER BY SENDING
AND RECEIVING PULSE PAIRS
� The ground stations are
typically co-located with
VORs
250 degree radial
Bearing 070 degrees
Range 25nm (Slant)
VOR