ENR 1.3  Instrument flight rules

ENR 1.3.1   Rules applicable to all IFR flights

As specified in the ICAO EUR Regional Supplementary Procedures (Doc 7030/4 - EUR), Chapter 1, paragraph 1.1.1.2, flights shall be conducted in accordance with Instrument Flight Rules when operated within or above the EUR RVSM airspace.Therefore, flights operating as General Air Traffic (GAT) within the FIR ZAGREB at or above FL 290, as described in ENR 2.1, shall be conducted in accordance with the Instrument Flight Rules.

ENR 1.3.1.1   Aircraft equipment

Aircraft shall be equipped with suitable instruments and with navigation equipment appropriate for the route to be flown and in accordance with the applicable air operations legislation.

ENR 1.3.1.2   Minimum levels

Except when necessary for take-off or landing, an IFR flight shall be flown at a level that is not below the established minimum IFR flight altitude or, where no such minimum flight altitude has been established:

  1. over high terrain or in mountainous areas (if higher than 1500 M), at a level which is at least 600 M (2000 FT) above the highest obstacle located within 8 KM of the estimated position of the aircraft;
  2. elsewhere than as specified in a., at a level which is at least 300 M (1000 FT) above the highest obstacle located within 8 KM of the estimated position of the aircraft.

Note: The estimated position of the aircraft will take account of the navigational accuracy which can be achieved on the relevant route segment, having regard to the navigational facilities available on the ground and in the aircraft.

The minimum flight altitudes are determined in accordance with relevant requirements of ICAO Annex 2 to the Convention on International Civil Aviation.

ENR 1.3.1.3   Change from IFR flight to VFR flight
ENR 1.3.1.3.1  An aircraft electing to change the conduct of its flight from compliance with the instrument flight rules to compliance with the visual flight rules shall notify the appropriate air traffic services unit specifically that the IFR flight is cancelled and communicate thereto the changes to be made to its current flight plan.
ENR 1.3.1.3.2  When an aircraft operating under the instrument flight rules is flown in or encounters visual meteorological conditions it shall not cancel its IFR flight unless it is anticipated, and intended, that the flight will be continued for a reasonable period of time in uninterrupted visual meteorological conditions.
ENR 1.3.1.3.3  Change from IFR flight to VFR flight shall only be acceptable when a message initiated by the pilot-in-command containing the specific expression ‘CANCELLING MY IFR FLIGHT’, together with the changes, if any, to be made to the current flight plan, is received by an ATS unit. No invitation to change from IFR flight to VFR flight shall be made by ATS either directly or by inference.
ENR 1.3.1.4   Position reports

In the airspace where ATS radar control service is not provided, a pilot shall report position as listed below:

  • aircraft call sign;
  • position;
  • time overhead;
  • flight level and
  • expected time overhead next position for VFR flight only

Time overhead may be omitted if the position is overflown at the time of position report.

In the airspace where ATS radar service is provided, pilot shall report position on the first contact with ATS unit and afterwards if requested by ATS unit. Position report shall read as listed below:

  1. aircraft callsign
  2. flight level

Speed and direction data shall be reported as well if assigned by ATS unit.

Notwithstanding above mentioned rules, when changing to an aerodrome control tower frequency, pilot shall report position as listed below:

  1. aircraft callsign
  2. position

Responsible ATS unit may request additional data or omit of prescribed position report elements, except aircraft call sign, if justified by traffic situation, ATS controller workload or frequency congestion and air traffic safety will not be jeopardised.

ENR 1.3.2   Rules applicable to IFR flights within controlled airspace

ENR 1.3.2.1  IFR flights shall comply with the provision of Section 8 of Regulation (EU) 923/2012 (SERA) when operated in controlled airspace.
ENR 1.3.2.2  An IFR flight operating in cruising flight in controlled airspace shall be flown at a cruising level, or, if authorized by ATS unit to employ cruise climb techniques, between two levels or above a level, selected from the table of cruising levels in Appendix 3 to SERA, except that the correlation of levels to track prescribed therein shall not apply whenever otherwise indicated in air traffic control clearances or specified by the competent authority in aeronautical information publications.

ENR 1.3.3   Rules applicable to IFR flights outside controlled airspace

ENR 1.3.3.1  Cruising levels - An IFR flight operating in level cruising flight outside of controlled airspace shall be flown at a cruising level appropriate to its track as specified in the table of cruising levels in Appendix 3 of Regulation (EU) 923/2012 (SERA), except when otherwise specified by the competent authority for flight at or below 900 M (3 000 FT) above mean sea level.
ENR 1.3.3.2  Communications - An IFR flight operating outside controlled airspace but within or into areas, or along routes, designated by the competent authority in accordance with SERA.4001(b)(3) or (4) shall maintain an air-ground voice communication watch on the appropriate communication channel and establish two-way communication, as necessary, with the air traffic services unit providing flight information service.
ENR 1.3.3.3  Position reports - An IFR flight operating outside controlled airspace and required by the competent authority to maintain an air-ground voice communication watch on the appropriate communication channel and establish two-way communication, as necessary, with the air traffic services unit providing flight information service, shall report position, as specified in SERA.8025 for controlled flights.

ENR 1.3.4   Free route airspace (FRA) general procedures

ENR 1.3.4.1   Applicability
ENR 1.3.4.1.1   Area of Applicability

For lateral and vertical limits of SECSI FRA see:

  • ENR 2.2 of AIP Albania, AIP Austria, AIP Bosnia and Herzegovina, AIP Croatia, AIP North Macedonia, AIP Serbia and Montenegro and AIP Slovenia.
  • ENR 6 of AIP Albania, AIP Austria, AIP Bosnia and Herzegovina, AIP Croatia, AIP North Macedonia, AIP Serbia and Montenegro and AIP Slovenia.
ENR 1.3.4.1.2   Time of Applicability

H24

ENR 1.3.4.1.3   Definitions

Free Route Airspace (FRA): A specified airspace within which users may freely plan a route between a defined entry point and a defined exit point, with the possibility to route via intermediate (published or unpublished) way points, without reference to the ATS route network, subject to airspace availability. Within this airspace, flights remain subject to air traffic control.

South East Common Sky Initiative (SECSI): Initiative of several States/ANSP-s on European Southeast Axis traffic flow to implement cross-border FRA.

South East Common Sky Initiative Free Route Airspace (SECSI FRA):
The airspace volume consisting of airspace volumes defined in ENR 2.1 and/or ENR 2.2 of the corresponding AIP-s where cross-border application of FRA is implemented.

Cross-border application of FRA (in SECSI FRA): Application of FRA operations in a manner to allow crossing of inter and intra ATC units boundaries regardless of State or FIR boundaries, at any position, if not otherwise regulated via the RAD.

FRA Arrival Connecting Point (A): A published Significant Point to which FRA operations are allowed for arriving traffic to specific aerodromes. The FRA relevance of such points shall be included in ENR 4.1/4.4 columns as (A). Indications on their use for arrivals to specific aerodromes shall be notified via the RAD.

FRA Departure Connecting Point (D): A published Significant Point from which FRA operations are allowed for departing traffic from specific aerodromes. The FRA relevance of such points shall be included in ENR 4.1/4.4 columns as (D). Indications on their use for departure from specific aerodromes shall be notified via the RAD.

FRA Horizontal Entry Point (E): A published Significant Point on the horizontal boundary of the Free Route Airspace from which FRA operations are allowed. The FRA relevance of such points shall be included in ENR 4.1/4.4 columns as (E). If this point has specific conditions of utilization, this shall be described in the RAD.

FRA Horizontal Exit Point (X): A published Significant Point on the horizontal boundary of the Free Route Airspace from which FRA operations are allowed. The FRA relevance of such points shall be included in ENR 4.1/4.4 columns as (X). If this point has specific conditions of utilization, this shall be described in the RAD.

FRA Intermediate Point (I): A published Significant Point or unpublished point, defined by geographical coordinates or by bearing and distance via which FRA operations are allowed. If published, the FRA relevance of such points shall be included in ENR 4.1/4.4 columns as (I). If this point has specific conditions of utilization, this shall be described in the RAD.

ENR 1.3.4.2   SECSI FRA flight procedures and flight planning procedures

SECSI FRA flight procedures and flight planning procedures are published in ENR 1.10 of the corresponding AIP-s. SECSI FRA constraints, exceptions and restrictions, if any, will be published via RAD and promulgated in accordance with ENR 1.10.