EQPS 4, 5, 6, 7, 8 Flashcards
(136 cards)
1
Q
What does ADS-B stand for
A
Automatic Dependent Surveillance Broadcast
2
Q
What does the acronym RADAR
A
Radio Detecting and Ranging
3
Q
What is the size of the wavelength of an area control radar
A
23-50cm
4
Q
What is the size of the wavelength of a typical approach control radar
A
3-10cm
5
Q
What wavelength and frequency would be preferable for a long range radar
A
Long wavelength low frequency
6
Q
What wavelength and frequency would be preferable for a short range radar
A
Short wavelength with high frequency
7
Q
Between what frequency band do radars typically operate
A
1-18 GHz
8
Q
What are some weather and operational characteristics of a long range radar
A
Less affected by weather. Less sensitive to small objects and take longer to update. But cover a wider reach
9
Q
Do weather radar use shorter or longer wavelength radar
A
Shorter
10
Q
What is the typical range of an approach radar
A
60nm
11
Q
What is the typical range of an area radar
A
240nm
12
Q
What is the concept of surveillance for the provision of air traffic services
A
Detect aircraft. Understand their position for the purpose of navigation and collision avoidance
13
Q
What is the basic principle of radar
A
Transmitter emits bursts of electromagnetic energy and listens for the echo of a reflection
14
Q
At an airport what is an SMR
A
Surface movement radar, accurately track aircraft & vehicles on the ground. But range can be limited and return cluttered
15
Q
What is the purpose of a weather radar on an aircraft
A
Identify poor weather ahead to avoid. Can vary distance looking at. Works laterally, limited help vertically
16
Q
On an aircraft what system identifies the distance of the aircraft from the ground
A
Ground proximity warning system GPWS
17
Q
What hardware allows a PSR to both transmit and receive
A
Duplexer
18
Q
How does a radar filter out returns of large object not in motion
A
Moving target detector (MTD), uses doppler effect
19
Q
What measure is used to express the range of a radar
A
Pulse repetition frequency (PRF). Number of pulses of a signal in a specific time, normally per second hundreds or thousands.
20
Q
If a radar has a higher pulse repetition frequency (PRF) what may be inferred about the range of the radar
A
Higher frequency shorter range as less time spent listening for returns
21
Q
In a radar why is it important to consider the pulse power
A
Need enough power to not only reach the aircraft but also get an echo return
22
Q
On an approach radar, how many rotations are typically made per minute
A
15 rotations per min, updating the screen every 4 seconds
23
Q
On an area radar, how many rotations are typically made per minute
A
10 rotations per min updating every 6 seconds
24
Q
Why does an approach radar update more regularly than an area radar
A
Approach radar can have higher pulse repetition frequency (PRF) as it is less concerned by range. More revolutions = more data
25
What determines accuracy for a radar
Beam width. Wider the beam the less accurate it gets. A PSR in theory could detect 2 aircraft as one return
26
If a radar return is increasing in frequency in its return is the object moving towards or away from the receiver
Moving towards
27
How does a primary radar determine if a return is valid or not and hence if it should be displayed
Doppler effect, if a return has a constant frequency then the object is not moving hence can be ignored
28
For a secondary surveillance radar what must an aircraft be equipped with
A transponder
29
What two frequencies does secondary surveillance radar operate on and what is their function
1030 MHz - Interrogator transmits and transponder receives
1090 MHz - Transponder transmits interrogator receives
30
What are the three SSR modes and their function
Mode A - Identity
Mode C - Height Info
Mode S - Further info from the flight deck
31
How can an aircraft tell what information a ground radar is requesting in secondary surveillance radar
The pulse repetition frequency of the pulse
32
How long is the transmitted PRF and number of pulses of a Mode A request
8 Microseconds
12 pulses received
33
How long is the transmitted PRF and number of pulses of a Mode C request
21 microseconds
11 Pulses received
34
How many mode A transponder combinations are possible
4096
35
What numbers can not be used in a squawk code
8 & 9
36
What is code callsign conversion in a transponder
The 4 digit squark code is converted to a flights unique callsign assuming the flight planning system has the pair stored
37
What is squawk ident
Command from controller where an aircraft will select ident on its transponder causing a pulsing circle on the aircraft on the radar display
38
What is the mode C function on a transponder
Displays height/altitude information depending on the altimeter setting
39
How are discrete and non-discrete SSR codes differentiated
A discrete code may only be used by a specific aircraft in the airspace
Non-discrete code can be used by multiple aircraft
40
In SSR code management what is ORCAM
Originating region code assignment method.
Departing aircraft maintain same code until fly into a region with a code conflict
41
In SSR code management what is CCAMS
Centralised code assignment and management system. Used by Eurocontrol & UK. Generated codes that wont conflict for the flight
42
What specific words are used to confirm a mode A code and mode C code is correct
Mode A codes are validated (correct squawk)
Mode C codes verified (correct altitude)
43
How a transponder codes allocated at local airports
Each ATC unit has a group of codes they allocate to local flights listed in the AIP
44
What are conspicuity codes for transponders
Denote a particular task or type of flight
45
What does conspicuity code 7000 mean
VFR flight typically outside CAS
46
What does conspicuity code 2000 mean
IFR flight typically outside CAS
47
What does conspicuity code 0017 mean
London air ambulance
48
What does conspicuity code 0033 mean
Paradropping
49
What does conspicuity code 0036 mean
Helicopter powerline/pipeline inspection
50
What does conspicuity code 7005 mean
Aircraft conducting high-energy manoeuvres
51
Why may an aircraft select an ATCU local conspicuity code on their transponder
To show they are listening to that units RT even if not receiving a service. Useful if they are near a danger area becoming active or if a controller needs to identify the aircraft
52
What does conspicuity code 7700 mean
Emergency situation
53
What does conspicuity code 7600 mean
Radio Failure
54
What does conspicuity code 7500 mean
Unlawful interference
55
What is the effect of antenna shadowing on SSR operations
SSR is line of sight so a/c have antenna on the top and bottom to negate shadowing issues
56
On NATS operational display equipment (NODE) what does a + signify
PSR return
57
On NATS operational display equipment (NODE) what does a X signify
SSR return
58
On NATS operational display equipment (NODE) what does a + & X overlayed signify
Both a PSR & SSR return
59
In surveillance what can MRT be understood to mean. What are its benefits
Multi Radar Tracking. Radar picture made up of info from multiple sources.
1)Get both PSR & SSR info.
2) View wide area
3) Maintain picture even if one source fails
60
What types of radar does a typical approach control use
Both PSR & SSR, but typically only 1 or 2 radar sources. Issue if it goes down. 40-60 mile range
61
What type of surveillance display would an aerodrome controller use
Aerodrome traffic monitor. Much closer in view of the local area, around 20 miles.
May also surface movement radar (SMR)
62
What are the benefits of a surface movement radar
Maintain throughput in low vis
Automatic warnings of potential conflict and deviation
Greater situational awareness
63
What are four uses of aerodrome traffic monitor
1) Determine landing order
2) Assist with longitudinal separation
3) Ensure conformity with departure clearance
4) See position of aircraft in circuits
64
What are some advantages of primary radar
1) Aircraft don't need a transponder
2) Detect weather (not always an advantage)
65
What are some disadvantages of primary radar
1) No altitude or speed info
2) Can pick up clutter, ignore slow aircraft
3) Slant range error gives false range
4) Can't see directly above the radar antenna
5) Has to be placed on high ground
6) Mirror imaging, return showing return twice
7) Weather distorting signal
66
What are some advantages of SSR
1) Less power needed
2) Generate more useful information
3) Quicker identification of aircraft in danger displaying emergency squawk
4) Immune to ground and weather clutter
67
What are some disadvantages of SSR
1) Reliant on the aircraft transponder functioning
2) Labels of stacked aircraft overlap. Can use vertical stack list to mitigate
3) Antenna shadowing
68
What does the S in mode S stand for
Selective addressing
69
How does a mode S transponder differentiate aircraft
Airframe ID rather than discrete mode A codes, many more combinations
70
How does the height reported differ for mode C vs mode S
Mode C 100ft accuracy
Mode S 25 ft accuracy
71
What process does a radar and mode S transponder go through to exchange information
Radar send out an all call interrogations, then can be more selective once a/c position and ID are known
72
What are the two versions of a Mode S transponder
Elementary and Enhanced
73
How does Mode S Elementary and enhanced differ
Elementary is much like mode A & C, just adds aircraft ID
Enhanced adds much more
74
What sort of additional information does Mode S enhanced add
Called down-linked airborne parameters
1) Selected flight level **can be added to data block**
2) Barometric pressure setting
3) Ground speed
4) Indicated air speed
5) Heading **can be added to data block**
6) Rate of climb/descent
75
What are some advantages of Mode S
1) Monitor non-conformance
2) Height info more accurate
3) RT reduced
4) Quicker identifier of unknown a/c
5) More effective TCAS
76
What are some disadvantages of Mode S
1) Expensive
2) DAP could be misleading. Aircraft could be being manually flown not to where the FMS thinks the flight is going
77
In aircraft equipment what is ADS
Automatic dependent surveillance
78
What is the difference between ADSB & ADSC
ADSB is broadcast, being sent continuously
ADSC is contract. To a specific ground station, sent via datalink
79
With ADSC what are the three typical contract forms
Demand: ATSU unit requesting single transmission or aircraft reporting emergency
Periodic: ATSU requesting info at set time intervals. Can specify what info sent
Event: ATSU request when a specific event occurs. Pass waypoint. Level/lateral deviation
80
What system does ADSC use to broadcast data
CPDLC, datalink. Satellite to ground station
81
What system does ADSB use to broadcast data
Plane to plane ADS-B in/out to ground station and other local aircraft.
ATC can take data from multiple ground stations for better coverage
82
How can ADS function when out of contact with ground stations
Space based, send data to comms satellites then onward to groundstation
83
What are the applications of ADS in aerodrome
ADSB can be integrated with surface movement radar, include vehicles in the display
84
What are the applications of ADS in approach
ADSB refreshes much quicker than PSR & SSR hence better awareness of hazardous situations. More efficient use of airspace
85
What are the applications of ADS in area
Much better coverage in remote areas hence can reduce separations and more efficient use of airspace
86
What benefit does ADS-B in give pilots
Better situational awareness of aircraft around them, more awareness than TCAS alone gives
87
What are the limitations of ADS
1) Not encrypted hence can be spoofed
2) Reliant of GPS functioning, not being jammed
3) Reliant on a/c carrying appropriate equipment
4) More requirements for more transponders meaning more congestion of the frequencies
88
What is MLAT in radar
Using multiple receivers to measure time distance of arrival of single hence locating source of the signal
89
What is LAM and WAM in the context of MLAT
Local area multilateration at aerodromes
Wide area multilateration covering boarder areas
90
How often can MLAT update compared to PSR/SSR
MLAT - Every second
PSR/SSR - 4-15 seconds
91
How does the passive and active MLAT system function
Passive, listening to signals sent as part of other systems (ADS/SSR)
Active, trigging a transponder response
92
What is the working principle of MLAT in equipment
Time Difference of Arrival (TDOA), how long a unique signal takes to reach multiple receivers
93
What transponder technologies can MLAT function using
Mode A, C, S, ADS-B
94
What is the use of MLAT for aerodrome
Used in advanced surface movement guidance and control systems (A-SMGCS)
Spotting conflicts, pilot deviations and assist planning
95
What is the use of MLAT for approach
Allows precision runway monitoring (PRM) making more efficient use of the airspace
96
What is the use of MLAT for area
Uses wide area multilateration (WAM). Adding coverage over large distances, use for oil rig helis. Checking altimeter accuracy at high levels
97
What are the limitations of MLAT
1) Requires multiple receivers to be maintained over a wide area
2) Has to be on the ground, not at sea
3) Ground stations must have the precise time
4) Requires aircraft to have a functioning transponder
98
What are the 5 major aircraft surveillance technologies
PSR
SSR
ADS-B
ADS-C
MLAT
99
What is azimuth
The angle relative to north of an object in the air
100
What can be said about the accuracy of primary surveillance radar. In NM & azimuth
Accuracy of 0.1nm
In Azimuth 0.15 degrees
Risks returning clutter
Less than SSR
101
What is the typical range of primary surveillance radar
220NM
102
What is the typical refresh rate of primary surveillance radar
4-15 seconds
103
What can be said about the reliability and redundancy of primary surveillance radar
Most have duplicated equipment on site
20000 hrs reliability
104
What can be said about the costs of a primary surveillance radar
No cost to aircraft
High site, set up and maintenance costs, more than SSR
105
What can be said about the accuracy of secondary surveillance radar. In NM & azimuth
0.03nm accuracy
0.07 degree azimuth accuracy
Labels can garble
Pilot error can cause labels to be misallocated
106
What can be said about the range of secondary surveillance radar
Up to 250 nm
107
What can be said about the refresh rate of secondary surveillance radar
4-15 seconds
108
What can be said about reliability/redundancy of secondary surveillance radar
Most have duplicated equipment on site
20000 hrs reliability
109
What can be said about the costs of a secondary surveillance radar system
High site, set up and maintenance costs, less than PSR
Small cost to aircraft to fit transponder
110
What can be said about the accuracy of ADS-B
Typically 0.1nm, depends on aircraft
111
What can be said about the range of ADS-B
Up to 250nm
112
What can be said about refresh rate of ADS-B
Every second
113
What can be said about reliability and redundancy of ADS-B
Typically duplicated, reliant on GPS functioning correctly
20000hr reliability
114
What can be said about the costs of an ADS-B system
Cheap to set up and maintain
Moderate cost to aircraft to fit the equipment
115
What can be said about the accuracy of an ADS-C system
Dependent on aircraft, typically 0.2nm
116
What is the range of an ADS-C system
200nm
117
What is the refresh rate of an ADS-C system typically
14 mins or when a defined event occurs
118
What is the reliability and redundancy of an ADS-C system
No redundancy
2000 hours reliability
119
What can be said about the cost of an ADS-C system
Minimal cost for ANSP, higher cost for aircraft to fit equipment
120
What can be said about the accuracy of an MLAT system
Depends on ground station set up, typically accurate to less than 0.1nm
121
What can be said about the range and coverage of an MLAT system
Depends on how ground stations set up
122
What is the refresh rate of an MLAT system
1 second mode S
2.5-5 seconds mode A/C
123
What can be said about the reliability and redundancy of an MLAT system
Multiple sites with multiple coms links, with enough receivers one being lost can be covered by the others
20000 hrs reliability
124
What can be said about the cost of an MLAT system
Moderate cost setting up for ANSPs, minimal cost for aircraft to carry transponders
125
In air traffic surveillance what is ARTAS
ATM surveillance track and & server. Europe wide, combining surveillance data. Helping coordination and capacity through shared surveillance
126
What is the Eurocontrol system to process and share surveillance data
ARTAS
127
In air traffic surveillance what is ASTERIX
All purpose structured Eurocontrol radar information exchange. Data format to share surveillance data in a common format
128
What is the Eurocontrol standard format for sharing surveillance data
ASTERIX
129
What is the working principle of surveillance data processing
Converting raw data from surveillance sources into digital formats a controller can use in their working position
Flight plans, ADS, transponders. Producing projected paths a trail dots
130
What is the advantage of using multiple sources of surveillance in one system
Get the best of each system and use that to mitigate against the drawbacks of a particular system
131
What are some examples of multiple surveillance technologies being used as a combined system
A-SMGCS (Advanced surface movement guidance & control system. Using surface movement radar, MLAT, SSR
Area and approach may combine PSR & SSR for multi-radar tracking (MRT). ADS-B may also be available
132
What are some uses of process surveillance data
Short term conflict alert (STCA)
Minimum safe altitude warning (MSAW
Area proximity warning (APM)
Controlled airspace infringement tool (CAIT)
133
In surveillance what tool alerts a controller if two aircraft may be getting too close to each other
Short term conflict alert. Joined by a line and pulse white, red if sep lost
134
In surveillance what tool alerts a controller if an aircraft is getting too close to the ground
Minimum safe altitude warning (MSAW) and approach path monitors (APM). Checking aircraft are clear of known terrain and following the approach path
135
In surveillance what tool alerts a controller if an aircraft goes into airspace it should not be in
Area proximity warning (APM)
Controlled airspace infringement tool (CAIT)
Aircraft changes colour on radar so controller can resolve the infringement quickly
136
Aside for the safety benefits that using processed surveillance data, what are some other benefits
Ensuring noise preferential routes (NPR) compliant
Environmental monitoring 3Di
Efficiency at airports. Monitor ground movements to pre plan maintenance and ensure the right resources are in the right place
