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In the following chapters some terms are used, which will be explained now.

Upstream/downstream sector

UPSTREAM SECTOR is the previous sector.
DOWNSTREAM SECTOR is the following sector.
In the flight profile of a pilot through the sectors A-B-C would be from the view of B: A = UPSTREAM; C = DOWNSTREAM

COP - Coordination Point or Reference Point

In most cases, the COP is a waypoint near the sector boundary where the handoff occurs. The COP acts as a reference point for both coordination partners. In the lists of most RGs, you will find the designation COPN for an Entry COP (i.e., a COP for an inbound flight) and COPX for an Exit COP (for an outbound flight from the sector).
The COP serves as an orientation during coordination, over which point the aircraft flies in or out. In the VATSIM environment, however, it is often advisable to specify the position because preplanning plays less of a role. Select a sensible position that the other party also knows. There is no point in telling a colleague in Munich that he should look in the direction of Aartalsee. Use, for example, VORs, large aerodromes or jointly known waypoints.

Transfer of control

The point at which CONTROL is transferred for a flight. As a controller, I may only issue instructions that change the trajectory of the flight (e.g., heading/directs, altitude instructions, speed instructions) if I have been handed CONTROL. If no other arrangement has been made verbally or in the LoA, the transfer of control takes place as soon as the aircraft has entered the next sector and has reached half the minimum distance to the common sector boundary. If 3NM separation is required, one has to keep 1.5NM to the border at any time - the same value, which the partner also ensures without coordination. Together you thus arrive at 3NM.

Silent transfer of control

In the Letters of Agreement, the SILENT TRANSFER OF CONTROL defines parameters under which flights can be sent to the receiving sector without prior coordination.

Transfer of communication

‚Ȇ Transfer of control! The (time) point at which the frequency is changed. Does not affect control or responsibilities.


Each controller has their own initials in the real center, i.e., two letters consisting of the first letter of the first and last name, if available. Each coordination is terminated by naming the initials. Accordingly, the initials have the meaning of a "contract signature" for the coordination made and signals to the counterpart that one has nothing more to say. If both parties have named their initials, the telephone conversation is ended.