4. SSR Identification - ATM1 Flashcards
Define Radar Contact
The situation which exists when the radar position symbol of a particular aircraft is seen and identified on a situation display.
Define Identification
The act of correlating a particular position indication with a specific aircraft target by means of laid down procedures
Define Validation
Validation is the task of checking that the correct code has been selected by the pilot and is shown on the situation display.
It is possible to achieve identification and validation simultaneously.
IF YOU ALLOCATE A SQUAWK YOU MUST VALIDATE AND VERIFY IT!
Define correlation
By means of a radar processor, SSR data may be correlated with stored flight plan data, enabling a code/callsign conversion to take place.
Unless correct validation procedures are carried out, the resulting correlation could give rise to incorrect data being displayed.
Define Verification
A check to confirm that the aircrafts Mode C read out is accurate within agreed parameters.
There are strict guidelines concerning the use of Mode C data which vary according to whether the readout is verified or not.
What SSR mode can be used for identification?
Mode A (SSR data) can be used to identify aircraft.
Following identification, outside controlled airspace, the controller shall inform the pilot that his aircraft has been identified.
It is no longer required to pass a position to the pilot unless the controller considers it necessary.
When using SSR and/or MLAT is used, how may an AC be identified? (5)
- Recognition of the aircraft identification in an SSR and/or MLAT label; (nb #1)
- Direct recognition of the aircraft identification of a Mode S-equipped aircraft in an SSR and/or MLAT label
- By transfer of identification (transfer of control)
- Observation of compliance with an instruction to set a specific code;
- Observation of compliance with an instruction to squawk IDENT.
What is validation?
Instruct the AC to squawk assigned code and match them on situation display.
Instruct AC to “squawk ident” and check code matches.
Matching a previous PSR target with assigned code for the flight
What if you are unable to validate?
Instruct pilot to reset squawk code.
If an error persists, instruct pilot to squawk A0000.
If an error still exists, instruct pilot to switch off transponder.
When is a Mode A code deemed valid?
When the code set can be recognised by the Code Assignment Plan to have been assigned by an ATC unit capable of validating the code providing the code has not been notified as being corrupt.
When is a Mode C code deemed valid?
Mode C can be assumed to have been verified if associated with a deemed validated Mode A code.
Verification may be achieved, if necessary, with the assistance of another ATSU.
If there’s an error with validating Mode C?
Request the pilot to “check altimeter setting and confirm level”
If still an error:
“Stop Squawk Altitude; or “Stop squawk Altitude, wrong indication” “Squawk 0000”– to indicate a data error (if independent switching of Mode C is not possible).
Condense
Transfer of identification
- Designation by automated means, provided that
only one position indication is indicated with no
possible doubt of correct identification; - Notification of the aircraft’s discrete SSR code or
aircraft address (telling the next unit the SSR) - Notification that the aircraft is SSR Mode S / ADS-
B-equipped with an aircraft identification feature
when SSR Mode S coverage is available
d) Notification that the aircraft is ADS-B-equipped
with an aircraft identification feature when
compatible ADS-B coverage is available;
e) Direct designation (pointing with the finger) of
the position indication, if the two situation
displays are adjacent or if a common
“conference” type of situation display is used;
-Designation of the position indication by reference
to bearing and distance from a geographical
position or nav facility, together with the track of
the observed position indication if the route of the
aircraft is not known to both controllers; (Radar handover - Over phone)
- a.
- Instructing an aircraft to change SSR code by
the transferring controller and the
observation of the change by the accepting
controller; or - Issuance of an instruction to the aircraft by
the transferring controller to ‘squawk IDENT’
and observation of this response by the
accepting controller.
In what form shall position information be passed? (5)
- As a well-known geographical position;
- Magnetic track and distance to a significant point, an en-route navigation aid, or an approach aid;
- Direction (using points of the compass) and distance from a known position;
- Distance to touchdown, if the aircraft is on final approach
- Distance and direction from the centre line of an ATS route.
