Level information consists of climb and descent clearances or instructions and reports of leaving, reaching and passing levels as detailed in the Level Instructions paragraphs in the General Phraseology lesson. Unless advice is received to the contrary, the aircraft is expected to vacate the level as soon as practicable. Under exceptional circumstances, if instant descent is required the word “immediately” is used.
FASTFLY 123 WHEN READY DESCEND TO FL 150 REPORT PASSING FL 180
DESCENDING TO FL 150 WILL REPORT PASSING FL 180 FASTFLY 123
FASTFLY 123 CLIMB IMMEDIATELY TO FL 280 DUE TRAFFIC
LEAVING FL 250 FOR FL 280 FASTFLY 123
An aircraft may request permission to leave controlled airspace by descent.
FASTFLY 123 REQUEST TO LEAVE CONTROLLED AIRSPACE BY DESCENT
FASTFLY 123 CLEARED FOR DESCENT REPORT PASSING 5500 FEET QNH 1012
LEAVING 6000 FEET WILL REPORT PASSING 5500 FEET QNH 1012 FASTFLY 123
An aircraft may request a clearance to climb or descend maintaining own separation while in VMC, in daylight, below 10000 feet, in airspace classes D and E. The clearance will include information on essential traffic.