Executive members: Aur Bogdan Dragos, Simos Dimitrios
Project Manager: Genadi Chankov & Alex Beavil
Signed: 08 March 2017
Implemented: 13 March 2017

General Regulations:

1) All traffic, including VFR traffic, intending to cross the international borders shall mandatorily submit a complete and valid flight plan for the entire journey.
Traffic not complying with the present rule shall not obtain by the Air Traffic Services any en route clearance beyond the airspace of the originating nation.
2) All traffic, IFR and VFR, submitting a complete and valid flight plan shall be considered as authorized to enter the foreign airspace, unless explicit denial is notified as part of the individual controller to controller coordination. Border crossing may be denied only in case of grave and proven operational limitations.
3) Handoff of communication shall be made at least 15 NM prior the established limit of jurisdiction.
4) En route clearance limit of VFR traffic crossing the international borders shall be set to the limit of jurisdiction itself. Handoff of communication for VFR traffic shall be performed at least 5 minutes before the aforesaid clearance limit, in order for the traffic to obtain the required en route clearance for transit within the foreign airspace.
5) Upon handoff, traffic shall be considered as NOT released for climb, descent, turns or change of airspeed unless otherwise specified in the provisions below.
6) Traffic is to be transferred clear of conflicts, and complying in particular with the following separation restrictions: – 15 NM longitudinal separation between two traffics at same Flight Level, when the preceding traffic is at equal or faster assigned speed or between two traffic at different Flight Level.
7) Traffic shall be handed off on a valid ATS route or on defined waypoints at RFL using the semi- circular cruising level system (even/odd), (West EVEN, East ODD).
8) To avoid additional workload in relation to the transfer of radar identification and separation on radar track the accepting unit should not perform the operation of “LABEL ASSUME” until it has made two-way contact with the traffic and the other ATC.
9) Both ATS units shall transfer aircraft on verified discrete codes assigned in accordance with the VATSIM Squawk Code Range, any change of SSR code by the accepting ATS Unit may only take place after the transfer of control point and the accepting ATS Unit shall be notified of any observed irregularity in the operation of SSR transponders.
10) Individual coordination between the active controllers takes priority over the provisions specified in the present LoA. In order to prevent unnecessary workload, individual coordination shall be limited to cases of effective need (e.g. weather cells, congested sectors/airports, aircraft performance limitations).
11) VFR flights are not permitted in the AoR of Bulgaria ACC and Greece ACC above FL195, unless specific coordination has been coordinated between the ATS Units.

vACC: Virtual Area Control Center
RFL: Requested Flight Level
ATS: Air Traffic Service
LoA: Letter Of Agreement
IFR: Instrument Flight Rules
VFR: Visual Flight Rules
SEL: Sector Exit List
SIL: Sector Inbound List
FIR: Flight Information Region
ACC: Area Control Centre
GAT: General Air Traffic
OAT: Operational Air Traffic
AAR: Air-to-Air Refuelling
UNL: Unlimited
AoR: Area of Responsibility
SFC: Surface
COP: Changeover point

General Air Traffic (GAT)
: All movements of civil aircraft, as well as all movements of State aircraft (including military, customs and police aircraft) when these movements are carried out in conformity with the procedure of ICAO.
Operational Air Traffic (OAT): All flights which do not comply with the provisions stated for GAT and for which rules and procedures have been specified by appropriate national authorities. Release for Climb: An authorization for the accepting unit to climb (a) specific aircraft before the transfer of control.
Note: The transferring unit remains responsible for separation within its Area of Responsibility unless otherwise agreed.
Release for Descent: An authorization for the accepting unit to descend (a) specific aircraft before the transfer of control.
Note: The transferring unit remains responsible for separation within its Area of Responsibility unless otherwise agreed.
Release for Turn: An authorization for the accepting unit to turn (a) specific aircraft away from the current flight path by not more than 45° before the transfer of control.
Note: The transferring unit remains responsible for separation within its Area of Responsibility unless otherwise agreed.
Area of Responsibility: An airspace of defined dimensions where a sole ATS unit has responsibility for providing air traffic services.

Area of responsibility & Airspace delegations
For the purpose of this LoA the boundary between the LGGG / LGMD FIR and LBSR FIR consists of a line connecting the waypoints: EVIVINIKTIRODIP

Special Areas within the Area of Common Interest

The purpose of this Letter of Agreement is to define the coordination procedures to be applied between SOFIA CTR and ATHENS CTR when providing ATS to General Air Traffic (IFR/VFR)

Coordination and Communication
Coordination and communication between Sofia and Athens shall be made by Euroscope internal coordination data exchange. If additional coordination is needed it shall be done by the internal radio communication system or text messages.

Hand-offs of traffic
Handoffs (transfer of communication) shall be made minimum 10 NM prior the respective boundary (FIR border, TMA border or delegated airspace). The ideal range for handoff between enroute sectors is 30nm. After handoff, traffic is NOT released for climb, descent or turns.

Spacing between two aircraft on same level and same routing shall be at least 10 NM if the speed of the following traffic is equal or less than the speed of the preceding traffic, otherwise at least 15 NM. Spacings deviating from this regulation shall be coordinated. Traffic from Sofia ACC to Athens ACC shall be transferred 2 minutes before RODIP. In case of no prior coordination, the spacing between the preceding traffic and following traffic shall be at least 15NM when radar transfer. In case with prior coordination the spacing between the preceding traffic and following traffic shall be at least 10NM when radar transfer.

If a specified level restriction cannot be met due to a lower RFL, traffic shall be handed off AT RFL, if this does not cause a conflict with any other traffic, otherwise traffic shall be coordinated. Traffic expected to be handed off to the next sector shall be first transfered using the Euroscope internal transferring system. The transfer of communications shall take place after or at same time as the transfer of control.

Level restrictions

General rules
Traffic exiting LGGG / LGMD with destination LBSR shall have even flight levels.
Traffic exiting LBSR with destination LGGG / LGMD shall have odd flight levels.

Handoff levels from LGGG / LGMD to LBSR

Destination Entry Point Cleared FL / MAX FL
LGTS -> LBSR EVIVI FL100-245 (even)

Handoff levels from LBSR to LGGG/MD

Destination Entry Point Cleared FL / MAX FL
LGGG/MD NIKTI/RODIP FL 245-460 (odd)
LGTS NIKTI FL165-245 (odd)
LGKV NIKTI FL165-245 (odd)

VFR Flights

A. Flights from LGGG/MD to LBSR.
1. VFR traffic flying outside published ATS routes, within class “G” airspace and which has established radio communication with ATHENS ACC, shall enter SOFIA FIR over COP EVIVI at 1000 M (3300 ft) height AGL or above.

B. Flights from LBSR to LGGG/MD.
1. VFR traffic shall enter ATHENS FIR over COP NIKTI or RODIP according to flight plan route.

C. The following limited information shall be exchanged between the two ACCs with regard to VFR flights:
1. VFR;
2. identification, type of aircraft and SSR code (if available);
3. routing and flight level, (altitude);
4. estimated time over COP;
5. ETO for the next two points or estimated time of arrival (if the aircraft is going to land at airports in SOFIA FIR or BUCHAREST FIR);
6. other information if necessary.

D. If no flight plan available for the receiving unit, the information above, shall be supplemented with the following:
1. departure and destination aerodromes;
2. further route of flight;
3. any additional information, if necessary.

E. For a group of VFR flights, the precise number of aircraft shall be emphasised as well as the callsign of the group leader.

Exchange of available data for VFR flights shall be transferred at least 20 (twenty) minutes prior to the time when the aircraft is estimated to pass the common FIR boundary.
A revision, if available, shall be forwarded whenever flight data have changed and/or the estimate varies by 5 (five) minutes or more.

To be announced

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