TWR controller position[PDF]
- 1 Introduction
- 2 TWR controller tasks
- 2.1 Choice of the active runways
- 2.2 Handling aircraft at the end of taxi
- 2.3 Taxi between closed parallel runways
- 2.4 Runway taking-off operation
- 2.5 Transfer after take-off
- 2.6 Handling IFR Inbound traffic
- 2.7 Maintaining separation between IFR aircraft
- 2.8 Landing operation
- 2.9 Transfer on ground
- 2.10 Aerodrome controller zone entry and exit conditions for VFR
- 2.11 Traffic information
- 2.12 Integration of VFR traffic into the aerodrome traffic circuit
- 2.13 Other task
- 3 Special IVAO procedures
- 4 See also
- 5 Reference
- 6 Author
- Take-offs and landings on all runways
- Active runway management (line-up, crossing, back-track…)
- Management of the aerodrome circuit
- Traffic separation during take-offs and landings
The TWR controller deals with:
- Departing aircraft or runway crossing clearances at holding point
- Inbound IFR aircraft established on the final approach track
- VFR traffic entering the control zone (CTR) and/or the aerodrome circuit
- Inbound IFR traffic before being established on the final approach track
- Any en-route IFR traffic
- Departing IFR traffic after take-off above 1000ft AGL.
- VFR traffic outside the control zone (CTR) limits or farther than 2 minutes from the CTR entry
TWR controller tasks
Choice of the active runways
In the case of a change in the active runway, he shall warn all the adjacent controllers about the runway change and he shall modify his ATIS.
The runway configuration is mainly chosen according to the wind direction, providing landings are executed with head wind.
Handling aircraft at the end of taxi
- Any IFR aircraft is established on final approach track at less than 5NM to 6NM.
- Any landing clearance has been issued to any aircraft, regardless of its distance from the threshold
- Any take-off clearance has been issued to any aircraft, if the departing aircraft will cross a holding point
If a time gain is needed, several aircraft can be lined up simultaneously at different holding points on the same runway.
Taxi between closed parallel runways
The controller has to issue a runway crossing clearance to each aircraft or issue a hold short clearance if the aircraft cannot clear the runway crossing. If not cleared, the aircraft must hold short (maintain holding point) and wait for a runway crossing clearance.
Runway taking-off operation
- Taxiing on runway
- An aircraft is on the runway in the section usable for take-off until end of runway.
- An aircraft is crossing the runway in the section usable for take-off
- An aircraft is taking off and has not yet overflown the runway endpoint or cleared the runway axis.
- An aircraft is already cleared to land
- An aircraft at a holding point is already cleared for take-off
The runway can be used as taxiway if this operation would reduce the taxi time with no impact on landing operation. The aircraft should be instructed to backtrack the runway, when the pilot-in-command requires to use maximum runway length for take-off operation.
Nevertheless, the TWR controller can instruct a runway crossing with keeping the traffic on the GND frequency. In this case, each runway crossing clearance has to be given by the TWR controller to the GND controller who transmits it to the aircraft on the GND controller frequency.
Transfer after take-off
In practice, traffic is transferred around 1000ft AGL and after passing the runway threshold.
Handling IFR Inbound traffic
Maintaining separation between IFR aircraft
The TWR controller is responsible for maintaining the separation of IFR arrivals under his control above separation minima.
The controller should not hesitate to issue speed restriction clearances to ensure that separation minima are fulfilled.
- The runway is occupied
- An aircraft is crossing the runway
- An aircraft is taking off but it has not yet passed the runway endpoint or the runway axis is not clear
- A previous aircraft is already cleared to land
- An aircraft at the holding point is already cleared for take-off
Transfer on ground
Once all runways are vacated, the TWR controller transfers the traffic to the GND controller.
Aerodrome controller zone entry and exit conditions for VFR
VFR traffic inbound from a non-controlled zone should contact the TWR controller between 1 and 2 minutes before entering the TWR controlled zone.
If the aircraft pursues its route over a class C or D airspace the TWR controller transfers it to the adjacent controller 2 minutes before exiting the TWR controlled zone.
If the aircraft pursues its route over an uncontrolled airspace or below a controlled zone the controller assigns the VFR a non-controlled transponder code and invites the pilot to switch to UNICOM 122.800MHz
An explicit pilot confirmation is the only guarantee that the given traffic information is able to provide the needed separation and that longitudinal and vertical separation limits are correctly met.
Integration of VFR traffic into the aerodrome traffic circuit
Several legs can be proposed or imposed by the controller to integrate a flight into the VFR traffic circuit:
- Integration from upwind side by crossing over the airport (at least 500ft above the circuit altitude) and joining the downwind leg
- Integration at the downwind leg (early or mid-downwind)
- Semi-direct integration at the base leg
- Direct integration on final (long final if the approach heading is lower than 30° with respect to the runway track orientation)
The position where the VFR aircraft is asked to join the traffic circuit should be chosen according to:
- The trajectory optimization or the easiest integration for the pilot
- The management of all aircraft flying in the traffic circuit (order in the circuit)
- The VFR traffic management with respect to IFR arrivals and departures
VFR transit operation
The TWR controller has to issue a transit clearance and ask to report over the controlled zone exit point. The clearance may contain indications on published or unpublished VFR transit routes, required transit altitude, indications on training zones depending on the activity within the area.
Go around handling
Example: non-stabilized approach, runway occupied, wind shear on final, loss of visual reference
The TWR controller has nothing to say with respect to this decision whose responsibility lies with the captain only. Following the go-around notification, it is recommended to issue an initial climb clearance, previously coordinated with the APP/DEP controller in charge of departures and in any case before transferring the aircraft.
If an aircraft is about to reach the runway threshold (2NM final) and the runway is not vacated, the TWR controller must issue a go-around clearance to this aircraft, unless already notified by the pilot. When the aircraft is going around it should be transferred to the DEP/APP controller in charge of departures.
Special IVAO procedures
Flight strips clearance
The TWR controller shall verify that flight strips are correctly filled, in particular SID (in the “Cleared WP” field) and flight level (in the “Cleared FL” field), for all departing traffic. In the case of a sudden pilot disconnection, the TWR controller must refill the flight strip before transferring the traffic to the next controller.
Release to UNICOM
In the absence of DEP or APP controllers, the TWR transfers traffic to the CTR controller if present or releases the pilot to UNICOM 122.800 when passing 1000ft.
In the case of aircraft coming from an uncontrolled zone, the TWR controller may send a FORCE ACT to the pilot 2 or 3 minutes before entry inside his controlled zone if the aircraft has not contacted him before. The controller should first assign him a transponder code.
Not responding pilots
The pilot of an outbound aircraft lining up, taking off without clearance or simply connecting on an active runway without communication with the controller must be warned by a FORCE ACT to invite him to contact the ATC. In the case of no answer, or if the pilot does not pick up the ATIS within 1 minute, or if he pursues taxiing, lining up or taking off, a new FORCE ACT must be sent, together with a private chat message (be careful to use proper language). Please check the pilot’s active frequency and communicate with other controllers of the aerodrome about his activity. If no answer from the aircraft is received, a supervisor can be called using the text command in COMMbox.
.WALLOP <reason of the call in English>
The TWR controller shall not use a FORCE ACT for contacting IFR approaching aircraft outside the final approach track. The pilot arriving at less than 12 NM from the airport may be contacted by a FORCE ACT if he is connected to UNICOM 122.800.
The TWR controller ensures that the transponder is set to:
- TX mode when penetrating an active runway.
- STAND BY mode when vacating the active runway
Setting the transponder to TX mode at the holding point and to STANDBY on the runway just after landing is tolerated.
- VID 150259 - Creation
DATE OF SUBMISSION
- 03:26, 14 May 2021
- This documentation is copyrighted as part of the intellectual property of the International Virtual Aviation Organisation.
- The content of this documentation is intended for aviation simulation only and must not be used for real aviation operations.