ATSEP BASIC QUESTIONS AND ANSWERS
What type of surveillance is regarded Non-cooperative, independent surveillance? -
Answers- PSR radar
What surveillance technique is ADS-B? - Answers- Cooperative, dependent
surveillance
What is the operating principle of the aircraft transponder? - Answers- To code a reply
on the 1090MHz frequency in response to a SSR radar interrogation
What is transmitted on a Mode C reply from a transponder? - Answers- Pressure
altitude
What is it called when replies from 2 aircraft overlap causing errors in extracting the
included data? - Answers- Garbling
What is a disadvantage of the classical SSR radar? - Answers- Garbling can occur if 2
aircraft are close in slant range and on the same bearing
What is a feature of Mode S? - Answers- Selective interrogations to reduce FRUIT
What is provided with Mode S enhanced surveillance? - Answers- Downlinked aircraft
parameters
What is a feature of the Monopulse SSR radar? - Answers- Improved azimuth
resolution and fewer pulses needed to determine position
ADS (automatic dependent surveillance) is a surveillance technique for use by ATS in
which: - Answers- Aircraft automatically provide, via data link, data from on-board
navigation systems
How is an aircraft detected by the PSR? - Answers- By reflected electromagnetic
energy transmitted from the radar
What is radar clutter on an ATM radar? - Answers- Unwanted targets
What is a limitation to the PSR radar? - Answers- No identification of received echoes
What is meant by PRI? - Answers- Pulse repetition interval
What is the purpose of the duplexer? - Answers- To alternately switch the antenna
between receiving and transmitting
What is variation? - Answers- The difference between true and magnetic north
, What is meant by instrument flight rules? - Answers- Flying by reference to instruments
in the flight deck, and navigation is accomplished by reference to electronic signals
What is the most common geodetic reference system with global coverage? - Answers-
WGS 84
What is meant by "dead reckoning"? - Answers- Determining position based on known
speed, course and elapsed time
What is meant by "course" in relation to aircraft movement? - Answers- The direction
over the ground the aircraft is moving
What is considered an integrity risk in relation to navigational performance? - Answers-
That undetected navigational system errors results in hazardously and misleading
information to an aircraft
On what frequency band is the DME operating on? - Answers- UHF
What is an advantage with the NDB? - Answers- The low operating frequency allow
reception beyond line of sight
How does the VOR create the different radials? - Answers- By transmitting 2 signals
with different phases
What information does the pilot get from a NDB? - Answers- Direction only to the
station
What is a disadvantage of the NDB? - Answers- The signal is subject to interference
and reflections
What airborne equipment is required to make use of a VDF? - Answers- A VHF radio
What principle is used in VOR bearing measurements? - Answers- Phase comparison
What elements are required for a ILS? - Answers- LOC, GP and markers or DME
What is a feature of ADS-B? - Answers- High update rate and simple, omnidirectional
receivers
Which airborne equipment supports the 1090ES messages? - Answers- The Mode S
transponder
What is the dominant ADS-B data link technology in Europe? - Answers- 1090
extended squitter
What type of surveillance is regarded Non-cooperative, independent surveillance? -
Answers- PSR radar
What surveillance technique is ADS-B? - Answers- Cooperative, dependent
surveillance
What is the operating principle of the aircraft transponder? - Answers- To code a reply
on the 1090MHz frequency in response to a SSR radar interrogation
What is transmitted on a Mode C reply from a transponder? - Answers- Pressure
altitude
What is it called when replies from 2 aircraft overlap causing errors in extracting the
included data? - Answers- Garbling
What is a disadvantage of the classical SSR radar? - Answers- Garbling can occur if 2
aircraft are close in slant range and on the same bearing
What is a feature of Mode S? - Answers- Selective interrogations to reduce FRUIT
What is provided with Mode S enhanced surveillance? - Answers- Downlinked aircraft
parameters
What is a feature of the Monopulse SSR radar? - Answers- Improved azimuth
resolution and fewer pulses needed to determine position
ADS (automatic dependent surveillance) is a surveillance technique for use by ATS in
which: - Answers- Aircraft automatically provide, via data link, data from on-board
navigation systems
How is an aircraft detected by the PSR? - Answers- By reflected electromagnetic
energy transmitted from the radar
What is radar clutter on an ATM radar? - Answers- Unwanted targets
What is a limitation to the PSR radar? - Answers- No identification of received echoes
What is meant by PRI? - Answers- Pulse repetition interval
What is the purpose of the duplexer? - Answers- To alternately switch the antenna
between receiving and transmitting
What is variation? - Answers- The difference between true and magnetic north
, What is meant by instrument flight rules? - Answers- Flying by reference to instruments
in the flight deck, and navigation is accomplished by reference to electronic signals
What is the most common geodetic reference system with global coverage? - Answers-
WGS 84
What is meant by "dead reckoning"? - Answers- Determining position based on known
speed, course and elapsed time
What is meant by "course" in relation to aircraft movement? - Answers- The direction
over the ground the aircraft is moving
What is considered an integrity risk in relation to navigational performance? - Answers-
That undetected navigational system errors results in hazardously and misleading
information to an aircraft
On what frequency band is the DME operating on? - Answers- UHF
What is an advantage with the NDB? - Answers- The low operating frequency allow
reception beyond line of sight
How does the VOR create the different radials? - Answers- By transmitting 2 signals
with different phases
What information does the pilot get from a NDB? - Answers- Direction only to the
station
What is a disadvantage of the NDB? - Answers- The signal is subject to interference
and reflections
What airborne equipment is required to make use of a VDF? - Answers- A VHF radio
What principle is used in VOR bearing measurements? - Answers- Phase comparison
What elements are required for a ILS? - Answers- LOC, GP and markers or DME
What is a feature of ADS-B? - Answers- High update rate and simple, omnidirectional
receivers
Which airborne equipment supports the 1090ES messages? - Answers- The Mode S
transponder
What is the dominant ADS-B data link technology in Europe? - Answers- 1090
extended squitter
