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General

Level Instructions

Air traffic control (ATC) instructions or clearances may contain a level assignment. Levels are transmitted using the following formats:

  • FLIGHT LEVEL (number)
  • (number) METRES
  • (number) FEET

Examples:

  • FLIGHT LEVEL 90
  • 300 METRES
  • 8500 FEET

Speed Control

ATC may instruct aircraft to adjust their speed for separation, sequencing, or operational efficiency.

ATC Speed Instructions:

  • REPORT SPEED
  • MAINTAIN (number) KILOMETRES PER HOUR (or KNOTS) [OR GREATER / OR LESS] [UNTIL (point)]
  • DO NOT EXCEED (number) KILOMETRES PER HOUR (or KNOTS)
  • MAINTAIN PRESENT SPEED
  • INCREASE (or REDUCE) SPEED TO (number) KILOMETRES PER HOUR (or KNOTS) [OR GREATER / OR LESS]
  • INCREASE (or REDUCE) SPEED BY (number) KILOMETRES PER HOUR (or KNOTS)
  • RESUME NORMAL SPEED
  • REDUCE TO MINIMUM APPROACH SPEED
  • REDUCE TO MINIMUM CLEAN SPEED
  • RESUME PUBLISHED SPEED

Canceling Speed Restrictions:

  • NO [ATC] SPEED RESTRICTIONS

Pilot Response to Speed Queries:

  • SPEED (number) KILOMETRES PER HOUR (or KNOTS)

Level Changes, Reports, and Rates

Climb Instructions:

  • CLIMB TO (level)
  • CLIMB TO AND MAINTAIN BLOCK (level) TO (level)
  • CLIMB TO REACH (level) AT (time or significant point)
  • CLIMB TO (level), REPORT LEAVING/REACHING/PASSING (level)
  • CLIMB AT (number) FEET PER MINUTE [OR GREATER/LESS]
  • CLIMB AT (number) METRES PER SECOND [OR GREATER/LESS]
  • REPORT STARTING ACCELERATION (or DECELERATION) (supersonic jets only)

Descent Instructions:

  • DESCEND TO (level)
  • DESCEND TO AND MAINTAIN BLOCK (level) TO (level)
  • DESCEND TO REACH (level) AT (or BY) (time or significant point)
  • DESCEND, REPORT LEAVING (or REACHING, or PASSING) (level)
  • DESCEND AT (number) FEET PER MINUTE [OR GREATER/LESS]
  • DESCEND AT (number) METRES PER SECOND [OR GREATER/LESS]

Pilot Request for Flight Level Change:

  • REQUEST DESCENT AT (time)

Instructions for Climb and Descent Modification

  • MAINTAIN AT LEAST (number) METRES (or FEET) ABOVE (or BELOW) (aircraft call sign)
  • STOP CLIMB (or DESCENT) AT (level)
  • CONTINUE CLIMB (or DESCENT) TO (level)
  • EXPEDITE CLIMB (or DESCENT) [UNTIL PASSING (level)]
  • WHEN READY CLIMB (or DESCEND) TO (level)
  • EXPECT CLIMB (or DESCENT) AT (time or significant point)

Adding Restrictions to Climb or Descent:

  • CROSS (significant point) AT (or ABOVE, or BELOW) (level)
  • CROSS (significant point) AT (time) OR LATER (or BEFORE) AT (level)
  • CRUISE CLIMB BETWEEN (levels) (or ABOVE (level))
  • CROSS (distance) MILES, (GNSS or DME) [(direction)] OF (DME station name) AT (or ABOVE or BELOW) (level)

Altimeter Setting Verification:

  • CHECK ALTIMETER SETTING AND CONFIRM (level)
  • REQUEST LEVEL (or FLIGHT LEVEL or ALTITUDE)

Emergency and ACAS Procedures

TCAS Alert Management:

Pilot response after initiating deviation due to ACAS (RA):

  • Pilot: TCAS RA
  • ATC: ROGER

When clear of conflict and returning to ATC clearance:

  • Pilot: CLEAR OF CONFLICT, RETURNING TO (assigned clearance)
  • ATC: ROGER (or alternative instructions)

When resuming original clearance after RA resolution:

  • Pilot: CLEAR OF CONFLICT, (assigned clearance) RESUMED
  • ATC: ROGER (or alternative instructions)

If ATC issues a contradictory instruction during an RA event:

  • Pilot: UNABLE, TCAS RA
  • ATC: ROGER

Vectoring and Maneuver Instructions

Vectoring for Spacing or Separation:

  • MAKE A THREE SIXTY TURN LEFT (or RIGHT) [reason]
  • ORBIT LEFT (or RIGHT) [reason]
  • MAKE ALL TURNS RATE ONE (or RATE HALF, or (number) DEGREES PER SECOND), START AND STOP ALL TURNS ON THE COMMAND "NOW"
  • TURN LEFT (or RIGHT) NOW
  • STOP TURN NOW

Vectoring Reasons:

  • DUE TRAFFIC
  • FOR SPACING
  • FOR DELAY
  • FOR DOWNWIND (or BASE, or FINAL)

Transfer of Control and Frequency Changes

ATC Transfer Instructions:

  • CONTACT (unit call sign) (frequency) [NOW]
  • WHEN READY CONTACT (unit call sign) (frequency)
  • REMAIN THIS FREQUENCY

Pilot Request for Frequency Change:

  • REQUEST CHANGE TO (frequency)
  • ATC: FREQUENCY CHANGE APPROVED

Aerodrome and Meteorological Information

Runway and Surface Conditions:

  • RUNWAY SURFACE CONDITION RUNWAY (number) (condition)
  • CAUTION CONSTRUCTION WORK (location)
  • CAUTION (reason) LEFT/RIGHT/BOTH SIDES OF RUNWAY (number)

Wind and Weather Reports:

  • [SURFACE] WIND (number) DEGREES (speed) (units)
  • RUNWAY VISUAL RANGE (or RVR) RUNWAY (number) (distance) (units)
  • PRESENT WEATHER (details)
  • TEMPERATURE [MINUS] (number) (and/or DEWPOINT [MINUS] (number))
  • QNH (number) [units]

Final Notes

  • Use standard phraseology to ensure clear and efficient communication.
  • Readbacks are mandatory for safety-critical instructions.
  • Vectoring, speed, and level changes should follow structured ICAO procedures.
  • Emergency procedures must be followed strictly, with priority given to aircraft in distress.

By maintaining strict adherence to phraseology standards, controllers and pilots can ensure efficient, safe, and professional communication in all operational scenarios.

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