Airspace and control phases

The phases are defined as:
Tower, Apron and Ground Control Phase
This control phase starts when traffic requests pushback from the gate and start up. It includes the taxi to the runway and the take off clearance.
Departure Control Phase
The departure phase starts when traffic is airborne in the initial climb out on the SID. It ends once the traffic is leaving the TMA, or passing a defined flight level - i.e. Top of Climb.
En-route Control Phase
En-route operations are considered to encompass the flight segments between the Top of Climb and Top of Descent events.
Approach Control Phase
The approach phase can start at the TOD in an E-TMA but certainly in the descent phase of a flight into the TMA. It includes the control of traffic to final approach and to landing of traffic on the runway.