The precise phraseology used in the transmission and acknowledgement of climb and descent clearances will vary, depending upon the circumstances, traffic density, and nature of the flight operations.
However, care must be taken to ensure that misunderstandings are not generated as a consequence of the phraseology employed during these phases of flight.
‘Level’ is a general term used when referring to altitude or flight level.
In the following examples the operations of climbing and descending are interchangeable and examples of only one form are given.
OO-ABC REPORT LEVEL
MAINTAINING 2500 FEET OO-ABC
OO-ABC REPORT PASSING FL100
OO-ABC WILCO (…)
OO-ABC PASSING FL100
OO-ABC MAINTAIN 3000 FEET
MAINTAINING 3000 FEET OO-ABC
OO-ABC CLIMB TO FL80
LEAVING 3000 FEET CLIMBING FL80 OO-ABC
REQUEST DESCENT OO-ABC
OO-ABC DESCEND FL 60
LEAVING FL 80 DESCENDING FL60 OO-ABC
FASTFLY 123 AFTER PASSING WEST TREE NDB DESCEND FL100
AFTER WEST TREE NDB DESCEND FL100 FASTFLY 123
Once given an instruction to climb or descend, a further overriding instruction may be given to a pilot.
FASTLFY 123 STOP DESCENT AT FL 90
STOPPING DESCENT AT FL 90 FASTFLY 123
FASTFLY 123 CONTINUE CLIMB TO FL 120
CONTINUING CLIMB TO FL 120 FASTFLY 123
FASTFLY 123 RECLEARED FL 120
RECLEARED FL 120 FASTFLY 123
Occasionally, for traffic reasons, a higher than normal rate of climb or descent may be required.
FASTLFY 123 EXPEDITE DESCENT TO FL 80
EXPEDITING DESCENT TO FL 80 FASTFLY 123
FASTFLY 123 CLIMB TO FL 240 EXPEDITE CLIMB UNTIL PASSING FL 180
CLIMBING TO FL 120 EXPEDITING UNTIL PASSING FL 180 FASTFLY 123
UNABLE TO EXPEDITE FASTFLY 123