Regulation (EU) No 923/2012 SERA : Standardised European Rules of the Air
Revision from March
SECTION 13 SSR Transponder
SERA.13001 Operation of an SSR transponder - Regulation (EU) 2016/1185
- When an aircraft carries a serviceable SSR transponder, the pilot shall operate the
transponder at all times during flight, regardless of whether the aircraft is within or
outside airspace where SSR is used for ATS purposes.
- Pilots shall not operate the IDENT feature unless requested by ATS.
- Except for flight in airspace designated by the competent authority for mandatory operation
of transponder, aircraft without sufficient electrical power supply are exempted from the
requirement to operate the transponder at all times.
GM1 SERA.13001 Operation of an SSR transponder - ED Decision
Pilots of aircraft engaged in formation join-ups are expected to continue operating the
transponder until established in formation. Once established in formation, all except the
lead aircraft should be instructed to ‘squawk standby’.
GM1 SERA.13001(c) Operation of an SSR transponder - ED Decision
Pilots of non-powered aircraft are also encouraged to operate the transponder during flight
outside airspace where carriage and operation of SSR transponder is mandatory.
SERA.13005 SSR transponder Mode A code setting - Regulation (EU) 2016/1185
- To indicate that it is in a specific contingency situation, the pilot of an aircraft
equipped with SSR shall:
- select Code 7700 to indicate a state of emergency unless ATC has previously directed
the pilot to operate the transponder on a specified code. In the latter case, a
pilot may nevertheless select Code 7700 whenever there is a specific reason to
believe that this would be the best course of action;
- select Code 7600 to indicate a state of radio-communication failure;
- attempt to select Code 7500 to indicate a state of unlawful interference. If
circumstances so warrant, Code 7700 should be used instead.
- Except in the cases described in (a) above, the pilot shall:
- select codes as instructed by the ATS unit; or
- in the absence of ATS instructions related to code setting, select code 2000 or
another code as prescribed by the competent authority; or
- when not receiving air traffic services, select code 7000 in order to improve the
detection of suitably equipped aircraft unless otherwise prescribed by the competent
- When it is observed that the code shown on the situation display is different from what has
been assigned to the aircraft:
- the pilot shall be requested to confirm the code selected and, if the situation
warrants, to reselect the correct code; and
- if the discrepancy between assigned and displayed codes still persists, the pilot
may be requested to stop the operation of the aircraft's transponder. The next
control position and any other affected unit using SSR and/or multilateration (MLAT)
in the provision of ATS shall be informed accordingly.
GM1 SERA.13005(a) SSR transponder Mode A code setting - ED Decision
If a pilot has selected Mode A Code 7500 and has been requested to confirm this code by ATC,
the pilot should, according to circumstances, either confirm this or not reply at all. If
the pilot does not reply, ATC should take this as confirmation that the use of Code 7500 is
not an inadvertent false code selection.
AMC1 SERA.13005(c) SSR transponder Mode A code setting - ED Decision
When requested by ATC to confirm the code selected, the pilot should:
- verify the Mode A code setting on the transponder;
- reselect the assigned code if necessary; and
- confirm to ATC the setting displayed on the controls of the transponder.
Mise en œuvre
En l’absence d’instructions de l’ATS, le pilote sélectionne :
- dans les régions d’information de vol de la France métropolitaine :
- le code 2000, lorsque l’aéronef est en vol IFR
- le code 7000, lorsque l’aéronef est en vol VFR
- dans les espaces aériens d’outre-mer exploités par l’administration française :
SERA.13010 Pressure-altitude-derived information - Regulation (EU) 2020/469
- When the aircraft carries serviceable Mode C equipment, the pilot shall continuously operate
this mode unless otherwise dictated by ATC.
- Unless otherwise prescribed by the competent authority, verification of the
pressure-altitude-derived level information displayed shall be effected at least once by
each suitably equipped ATS unit on initial contact with the aircraft concerned or, if this
is not feasible, as soon as possible thereafter.
GM1 SERA.13010(b) Pressure-altitude-derived information - ED Decision
ERRONEOUS LEVEL INFORMATION IN AIR TRAFFIC CONTROL SERVICE PROVISION
- If the displayed level information is not within the approved tolerance value or when a
discrepancy in excess of the approved tolerance value is detected subsequent to
verification, the pilot should be advised accordingly and requested to check the
pressure setting and confirm the aircraft’s level.
- If, following confirmation of the correct pressure setting, the discrepancy continues to
exist, the following action should be taken by ATC according to circumstances:
- request the pilot to select and operate an alternative transponder, if
available, and re-verify that the displayed level information is within the
approved tolerance; or
- request the pilot to stop Mode C or ADS-B altitude data transmission, provided
this does not cause the loss of position and identity information, and notify
the next control positions or ATC unit concerned with the aircraft of the action
- inform the pilot of the discrepancy and request that the relevant operation
continue in order to prevent loss of position and identity information of the
aircraft and, when so prescribed by the local instructions, override the
label-displayed level information with the reported level. In addition, the ATC
unit should notify the next control position or ATC unit concerned with the
aircraft of the action taken.
- It should be highlighted that ACAS will accept mode C replies that are erroneous, and it
is possible to issue an RA based on these inputs. When the measures described in (b)(1)
cannot be implemented, the controller should take into account the likelihood of
generating ACAS RA in the provision of ATS.
GM2 SERA.13010(b) Pressure-altitude-derived information - ED Decision
ERRONEOUS LEVEL INFORMATION IN FLIGHT INFORMATION SERVICE PROVISION
The procedures for the verification of pressure-altitude-derived displayed information in the
provision of flight information service should be established by the competent authority
taking into consideration GM1 ATS.TR.155(f) in EASA ED Decision 2020/008/R.
SERA.13015 SSR transponder Mode S aircraft identification setting - Regulation (EU)
- Aircraft equipped with Mode S having an aircraft identification feature shall transmit the
aircraft identification as specified in Item 7 of the ICAO flight plan or, when no flight
plan has been filed, the aircraft registration.
- Whenever it is observed on the situation display that the aircraft identification
transmitted by a Mode S-equipped aircraft is different from that expected from the aircraft,
the pilot shall be requested to confirm and, if necessary, re-enter the correct aircraft
- If, following confirmation by the pilot that the correct aircraft identification has been
set on the Mode S identification feature, the discrepancy continues to exist, the controller
shall take the following actions:
- inform the pilot of the persistent discrepancy;
- where possible, correct the label showing the aircraft identification on the
situation display; and
- notify the next control position and any other unit concerned using Mode S for
identification purposes that the aircraft identification transmitted by the aircraft
SERA.13020 SSR transponder failure when the carriage of a functioning transponder is mandatory
- Regulation (EU) 2016/1185
- In case of a transponder failure after departure, ATC units shall attempt to provide for
continuation of the flight to the destination aerodrome in accordance with the flight plan.
Pilots may, however, be expected to comply with specific restrictions.
- In the case of a transponder which has failed and cannot be restored before departure,
- inform ATS as soon as possible, preferably before submission of a flight plan;
- insert in Item 10 of the ICAO flight plan form under SSR the character ‘N’ for
complete unserviceability of the transponder or, in case of partial transponder
failure, insert the character corresponding to the remaining transponder capability;
- comply with any published procedures for requesting an exemption from the
requirements to carry a functioning SSR transponder.
GM1 SERA.13020(a) SSR transponder failure when the carriage of a functioning
transponder is mandatory - ED Decision 2016/023/R
TRANSPONDER FAILURE AFTER DEPARTURE
When an aircraft experiencing transponder failure after departure is operating or expected to
operate in an area where the carriage of a functioning transponder with specified
capabilities is mandatory, the ATC units concerned should endeavour to provide for
continuation of the flight to the aerodrome of first intended landing in accordance with the
flight plan. However, in certain traffic situations, either in terminal areas or en-route,
continuation of the flight may not be possible, particularly when failure is detected
shortly after take-off. The aircraft may then be required to return to the departure
aerodrome or to land at the nearest suitable aerodrome acceptable to the operator concerned
and to ATC.
GM1 SERA.13020(b) SSR transponder failure when the carriage of a functioning
transponder is mandatory - ED Decision 2016/023/R
TRANSPONDER FAILURE BEFORE DEPARTURE
In case of a transponder failure which is detected before departure from an aerodrome where
it is not practicable to effect a repair, the aircraft concerned should be permitted to
proceed, as directly as possible, to the nearest suitable aerodrome where repair can be
made. When granting clearance to such aircraft, ATC should take into consideration the
existing or anticipated traffic situation and may have to modify the time of departure,
flight level or route of the intended flight. Subsequent adjustments may become necessary
during the course of the flight. Note that Article 4(4) of Commission Implementing
Regulation (EU) No 1207/201118 also addresses this issue.