Koordination

General

There are two major coordinations: Release Requests and Approval Requests. A release coordination is always concerning the sector you just received an aircraft from (or that the aircraft is not planned to cross), while an approval request always concerns the next sector.

When another station calls, you should always listen at least until you know what he wants, then you can say standby until you are ready.

For the purpose of this guide, we make use of the following abbreviations:

S: Sending station
R: Receiving station

Release Request / Transfer of Control

Unless otherwise specified in a Letter of Agreement, control is usually transferred at the sector border. The receiving station therefore needs a release for instructions inside the sector of the sending station:
R: REQUEST RELEASE *OF* (call sign)
S: RELEASED *AT (time) / OVER / ABEAM (significant point) / WHEN PASSING (level)* *(conditions / restrictions)*
R: IS (call sign) RELEASED *FOR CLIMB/DESCENT/TURN*
S: (call sign) NOT RELEASED *UNTIL (time or significant point)*
S: UNABLE RELEASE (call sign) *TRAFFIC IS (details)*
S: RSYD (call sign)
'RSYD' = Released subject to your discretion

Example: EDDF outbound via TOBAK is at 240 but still below FFM. FUL calls FFM.

FUL: Fulda hello. Request Release DLH148
FFM: Released for climb FL 270
FUL: DLH148 released for climb FL270.

Approval Request

Approval request for en-route flights

S: APPROVAL REQUEST *(significant point) (call sign)*
R: GO AHEAD
S: (details)
R: *REQUEST* APPROVED *(restrictions)*
R: UNABLE (alternative instructions)

EDDF outbound via MARUN NATSU is climbing 240 and will have to level off, EDGG GIN calls MUAC Solling (SLN):

EDGG: Gießen hello. Approval request inbound NATSU DLH016.
SLN: Go ahead.
EDGG: Request DCT DLE and a higher level.
SLN: Approved DCT DLE and FL320.
EDGG: DLH016 approved for DCT DLE and FL320.

Note: EDGG GIN now has to call FFM for a climb release

Approval request for departures

Departures from smaller airports sometimes need the approval of the adjacent lower sector depending on local agreements. If needed an approval request shall be coordinated as follows:

S: APPROVAL REQUEST (call sign) DEPARTURE FROM (location)
R: (aircraft type) TO (destination) [if FPL is received] / NO DETAILS [if no FPL is received] S: (details) R: *REQUEST* APPROVED *(restrictions)* R: UNABLE (alternative instructions)

EDMA outbound via KPT9G needs to be approved from München Approach (North Low sector - DMNL) so EDMA Tower (MA-TWR) calls DMNL:

WIP

Weiterführende Links

Skybrary: ATC Unit Coordination (englisch)
Youtube: Verbal Coordination on Vatsim (englisch)