Course 7 - Section 21 - Surveillance, Systems and Equipment

Question 1

Name the four types of technology that surveillance systems rely on

Answer 1

Radar
Multilateration (MLAT)
Surface Movement Guidance and Control System (SMGCS)
Automatic Dependent Surveillance-Broadcast (ADS-B)

Question 2

Radar

Answer 2

Radio Detection and Ranging

a detection system that uses radio waves as an electronic form of echolocation to determine position of objects

By measuring the amount of time that elapses between transmission and reflected return, the distance of an object from the antenna can be calculated. This is how
RANGE is determined

A rotating antenna is used to measure the azimuth (direction) of the reflected pulse, this is how bearing is determined

Question 3

PSR

Answer 3

Primary surveillance radar (PSR) systems rely on reflected radio waves

The performance of PSRs can be affected by atmospheric moisture like rain or snow or a large flock of birds. The interrogation-reply system used in SSR eliminates those types of false returns

However THE DETECTION AND RANGE FOR BOTH PRIMARY AND SECONDARY SURVEILLANCE SYSTEMS IS LIMITED TO THE LINE OF SIGHT

Question 4

SSR

Answer 4

Secondary Surveillance Radar

Secondary surveillance radar systems use an interrogation-reply system. The radar system broadcasts a request for information and a transponder on board each individual aircraft replies with encoded data such as its identity and altitude

With SSR, flight data processing matches an aircraft’s response to a specific code to its flight plan to generate an identification tag on the radar’s display

Question 5

Squawk Codes

Answer 5

Each aircraft’s SSR transponder has four individually selectable digits (from 0 to 7) for a potential of 4096 unique codes.

The latest version of transponders (Mode S) rely on 24-bit addressing, allowing each aircraft worldwide to have its own, unique identification code

The data stream from mode S contains significantly more data compared to previous generation of transponders

Question 6

RSE

What is it and list the two types

Answer 6

Radar Site Equipment

Radar site equipment refers to the housing that contains radar and electronic equipment necessary for detecting aircraft

RSE is located at most major airports and at other strategic locations where it provides approach and enroute radar surveillance

Two types of traditional RSE:
- Terminal Surveillance Radar (TSR)
- Independent Secondary Surveillance Radar (ISSR)

Question 7

Radar Site Equipment

TSR

Answer 7

Terminal Surveillance Radar

Located at major canadian airports, terminal surveillance radar (TSR), consists of co-located PSR and SSR antennae

TSR provides digitized PSR and SSR targets as well as digitized weather data

There are 27 TSR installations across canada

Question 8

Radar Site Equipment

ISSR

Answer 8

Independent Secondary Surveillance Radar

Installed at strategic locations across Canada, independent secondary surveillance radar (ISSR) provides accurate range and azimuth positioning for aircraft equipped with transponders (no primary!)

There are 20 ISSR installations across Canada

Question 9

Radar - A note on terminology

Answer 9

“radar” and “surveillance” have been in the past used interchangeably. However, radar refers to a single form of surveillance tech.

“Surveillance” is the all-encompassing term that includes both traditional radar as well as more modern surveillance technologies

Question 10

MLAT

Answer 10

Multilateration

MLAT is a surveillance technology that uses the measured differences in times of arrival of energy waves

The energy waves used in multilateration are an aircraft’s “replies” to normal SSR interrogation signals, which are captured by multiple strategically located ground stations instead of a single rotating antennae

Position is accurately determined by comparing the fractional differences in times that a response to an interrogation signal is received at different stations

Question 11

SMGCS

Answer 11

Surface Movement Guidance and Control System

At larger airports, surface movement guidance and control system is used to provide airport controllers with highly accurate position information on aircraft and vehicles operating on the surface of the airport. It uses similar principles as PSR. Think of SMGCS as primary radar located at the top of a control tower and pointed at the ground

SMGCS surveillance data is presented to controllers as a display of aircraft and vehicle positions overlaid on a map of the airport’s runways and taxiways

The system provides a continuously updated display of all airport surface operations that controllers can use to spot potential collisions

Question 12

ADS-B

Answer 12

Automatic Dependent Surveillance-Broadcast

ADS-B is a surveillance technology that allows an appropriately equipped and certified aircraft to determine its position via satellite navigation and periodically broadcast that information for surveillance purposes. ADS-B can be ground based or space based

ADS-B is AUTOMATIC in that it requires no input from the pilot or external sources

it is DEPENDENT in that it depends on data from the aircraft’s navigation systems. Position information that is broadcast comes from GNSS systems

Question 13

Squits

Answer 13

ADS-B surveillance systems rely on aircraft automatically broadcasting their identification, position, and altitude approximately twice per second using expanded Mode S transponder technology

These broadcasts (also called squits) are received by the ground, airborne or space-borne receivers, and are processed for display to operational staff

ADS-B receivers have been integrated into the latest generation of Iridium communication satellites (a worldwide constellation of more than 75 satellites that provide coverage for voice and data communication for hand-held satellite phones and other receivers), making this type of surveillance technology available everywhere on earth

Question 14

Surveillance Technology

Additional Equipment Requirements

Primary Surveillance Radar (PSR)

Answer 14

In a PSR environment, NO ACTION OR ADDITIONAL EQUIPMENT IS REQUIRED

For the purpose of verifying identify, an aircraft may be required to carry out a turn or report a position

Question 15

Surveillance Technology

Additional Equipment Requirements

SSR and MLAT

Answer 15

In both SSR and MLAT surveillance environments, THE AIRCRAFT ARE REQUIRED TO CARRY TRANSPONDERS capable of providing response to ground based interrogation signals

Question 16

Surveillance Technology

Additional Equipment Requirements

SMGCS

Answer 16

SMGCS data is limited to the surface manoeuvering areas of larger airports and REQUIRES NO ADDITIONAL EQUIPMENT for either vehicles or aircraft

Question 17

Surveillance Technology

Additional Equipment Requirements

ADS-B

Answer 17

In an ADS-B surveillance environment AIRCRAFT USE GNSS to determine position. That position information IS BROADCAST BY A MODE S TRANSPONDER for subsequent processing and display

• GNSS AND MODE S required!

Question 18

Surveillance Technology

Cooperation from Aircraft

PSR, SMGCS, SSR, MLAT, ADS-B

Answer 18

PSR does not require cooperation from aircraft

SMGCS does not require cooperation from aircraft or vehicles

SSR and MLAT depend on active replies from the aircraft’s transponder

ADS-B use GNSS and a broadcast link to relay their position to receiver stations which is then relayed to ATC facilities

Question 19

Surveillance Technology

Accuracy

PSR and SSR

Answer 19

A radar system’s accuracy degrades with weather conditions, extended ranges and aircraft altitude

with PSR and SSR, the radiated beam becomes wider as the distance between the antenna and aircraft becomes greater, making the position information LESS ACCURATE

Question 20

Surveillance Technology

Accuracy

MLAT or SMGCS

Answer 20

Because the distances under surveillance by MLAT or SMGCS are not as great as PSR or SSR, those systems ARE NOT AS SUSCEIPTIBLE TO SOME OF THE ISSUES OF ACCURACY associated with PSR and SSR

In addition, the frequency in which SMGCS operates makes it less susceptible to weather related interference

Question 21

Surveillance Technology

Accuracy

ADS-B

Answer 21

With ADS-B, data accuracy IS NOT SUSCEPTIBLE to the position of the aircraft or the length of time between radar sweeps.

Received signal quality can still be affected by the range from the aircraft to the receiver, radio frequency interference, obstacles, or weather

Space based ADS-B can be affected by solar activity. However, built-in detection recognizes and discards erroneous signals so that the system maintains FULL ACCURACY

Question 22

Surveillance Technology

Accuracy affected by weather or distance?

Summary

Answer 22

Accuracy affected by weather or distance?

PSR - Yes
SSR - Yes
MLAT - Yes, but to a lesser degree than PSR or SSR
SMGCS - Yes, but to a lesser degree than PSR or SSR
ADS-B - minimally

Question 23

Surveillance Data Processing

Describe data processing and list the two systems used

Answer 23

Raw surveillance data must be processed before it can be used

There are several systems that process the data and display it for use by ATS personnel.

Here are two of them:

FUSION
Canadian Automated Air Traffic System (CAATS)

Question 24

FUSION

Answer 24

Fusion is one of the surveillance data processing systems used at NAV CANADA

As its name implies, Fusion is capable of merging surveillance information from multiple sensors into display targets that can be viewed by ATS personnel

FUSION takes information from a variety of tracking systems and fuses them into each other to present THE MOST ACCURATE POSITION INFORMATION to operational staff

FUSION receives input from several surveillance sources, including RSE, ADS-B, SMGCS and MLAT

Question 25

FUSION advantages

Answer 25

The inputs from different surveillance sources are combined to eliminate any holes or gaps in surveillance coverage

Fusion also eliminates the need to switch between different radar sources to better view the traffic

PSR weather returns are digitized and presented in two intensities, WEAK AND STRONG. The brightness of these weather returns is presented in a way that does not obscure any targets

The FUSION system also provides the controller with SHORT TERM CONFLICT ALERTS (STCAs)

Question 26

CAATS

Answer 26

Canadian Automated Air Traffic System

CAATS is an electronic flight data processing system that stores and correlates flight information–such as flight plans and airport departure and arrival information–with surveillance data, flight trajectory, and communications

For ATS personnel, CAATS SIMPLIFIES FLIGHT DATA MANAGEMENT

For example. when a flight plan is entered into CAATS, a profile of that flight is created. CAATS takes note of all the sectors, towers, and flight service stations that the flight will pass through. At appropriate intervals it distributes flight data to the ATS positions responsible for the flight.

Everytime flight plan or clearance information changes, CAATS modifies the flight profile and, if necessary, generates new flight data with updated information at each position.

CAATS GIVES ATS PERSONNEL ACCESS TO THE CORRECT INFORMATION ON A TIMELY BASIS

Question 27

CSiT

Answer 27

CAATS situational display

the CAATS situational display (CSit) is the interface between the controller and the CAATS system. Surveillance and accompanying flight data are displayed on a large flatscreen monitor

Controllers update critical flight data such as altitude and speed assignments through menus on the CSiT display

Question 28

IIDS

(There’s a list)

Answer 28

Integrated Information Display System

The integrated information display system (IIDS) provides integrated access to a wide variety of essential operational information, including:

• Operational Information Display System (OIDS-R)
• Computerized Video Information Display System (CVIDS)
• NAV CANADA Auxiliary Radar Display System (NARDS)
• Extended Computer Display System (EXCDS)

Question 29

OIDS-R

Answer 29

Operational Information Display System-Replacement

OIDS-R gathers, formats, and displays aviation weather for use by ATS personnel

The system collects hourly weather observations, aerodrome forecasts, SIGMETs, AIRMETs and PIREPs and presents them in an easy to read format

OIDS-R also monitors and displays the status of local airfield NAVAIDs and runway lighting configurations

Question 30

CVIDS

Answer 30

Computerized Video Information Display System

CVIDS contains graphics files that show useful operational information, such as approach plates and local emergency procedures

Question 31

NARDS

Answer 31

NAV CANADA auxiliary radar display system

NARDS is used for displaying and manipulating surveillance targets and flight plans

NARDS typically occupies one of the two monitors at an IIDS workstation

In the ACC, NARDS is used to display surveillance targets IN THE EVENT THAT CAATS, CSiT, or FUSION fail

in towers and flight service stations it is used as the main surveillance display

Question 32

EXCDS

Answer 32

Extended Computer Display System

EXCDS is a flight plan manipulation and display system that provides real-time flight plan status information to ATS personnel in different geographical locations

EXCDS reduces the amount of verbal communication required to deal with flight data transactions by automating most of the repetitive operations

Question 33

VSCS

Answer 33

Voice Switching and Control System

VSCS is the primary communication technology used in ATS

VSCS uses digital switching technology, which is the same technology used by phone companies

This system includes a touchscreen input device that allows you to select which frequencies and phone lines to use. You communicate through a headset

Question 34

ATIS

Answer 34

Automatic Terminal Information Service

Many control towers and flight service stations use the ATIS

ATIS provides a continuous broadcast of recorded aeronautical information for selected airports

It is used to notify arriving and departing aircraft of important data such as

• Current Surface Weather
• Active Runways
• Runway and taxiway conditions
• Communication Frequencies

ATIS Broadcasts are updated by ATS personnel who create a voice recording for the broadcast

Question 35

D-ATIS

Answer 35

Data Link ATIS (D-ATIS)

automates the distribution of ATIS information and can be installed on the IIDS platform

ATIS data is passed automatically to the text to voice generation system (TVGS) for broadcast

D-ATIS messages are also passed to the ACC for further dissemination

Question 36

Rules Regarding Equipment Operation

List the rules!

Answer 36

• Test all equipment
• Do not tamper with equipment
• Display irregular operating status information
• Report malfunction
• Do not use malfunctioning equipment