3.3 Common Controller Errors
3.3.1 General
During Aerodrome Control operations, certain errors are commonly observed in developing controllers.
Early recognition and correction of these errors is essential to maintaining safe, orderly, and efficient control.
Controllers shall actively monitor their own performance and take corrective action where required.
3.3.2 Loss of Situational Awareness
Loss of situational awareness occurs when the controller no longer maintains an accurate mental picture of traffic.
Causes
- Excessive focus on a single aircraft
- High workload without effective prioritisation
- Inadequate scanning of the aerodrome environment
Indicators
- Uncertainty regarding aircraft position or sequence
- Conflicting or inappropriate instructions
- Delayed response to developing situations
Required Actions
The controller shall:
- Continuously scan all aircraft and runway activity
- Maintain a clear mental or visual sequence
- Reduce workload where necessary to regain control
3.3.3 Late Decision Making
Late decision making results in reactive control and increases the risk of unsafe situations.
Examples
- Delayed go-around instructions
- Late sequencing resulting in reduced spacing
- Failure to anticipate runway conflicts
Required Actions
The controller shall:
- Make decisions early and proactively
- Plan traffic sequence in advance
- Anticipate conflicts before they develop
3.3.4 Incorrect Runway Separation
Failure to maintain runway separation is a critical safety error.
Examples
- Issuing landing clearance while the runway is occupied
- Issuing take-off clearance with traffic on short final
- Allowing conflicting runway movements
Required Actions
The controller shall:
- Verify runway status before issuing any clearance
- Ensure required separation exists at all times
- Withhold clearances if any doubt exists
3.3.5 Poor Communication
Unclear or incorrect communication may result in misunderstandings and unsafe situations.
Examples
- Non-standard phraseology
- Incomplete or ambiguous instructions
- Failure to confirm readback where required
Required Actions
The controller shall:
- Use standard ICAO phraseology at all times
- Issue clear, concise, and unambiguous instructions
- Ensure critical instructions are correctly understood
3.3.6 Ineffective Prioritisation
Failure to apply correct priorities may lead to loss of separation or unsafe operations.
Examples
- Focusing on efficiency over safety
- Managing low-priority tasks during high workload
- Delaying critical decisions
Required Actions
The controller shall:
- Apply the established priority order at all times
- Focus on safety and separation first
- Defer non-essential tasks during high workload
3.3.7 Runway Incursion Risk
Failure to adequately monitor runway activity may result in a runway incursion.
Examples
- Issuing crossing clearance without full runway protection
- Forgetting an aircraft or vehicle on the runway
- Conflicting runway instructions
Required Actions
The controller shall:
- Maintain continuous awareness of runway occupancy
- Monitor all runway entries and exits
- Take immediate action to prevent or resolve incursions
3.3.8 Key Principle
Most controller errors result from:
- Loss of situational awareness
- Poor decision making
- Inadequate prioritisation
The Tower Controller shall actively manage workload, maintain awareness, and act proactively to prevent errors before they occur.