by Jonathan M. Stern
Clearance Delivery is an air traffic controller whose function is to coordinate with other ATC facilities and provide departing aircraft with an instrument flight clearance The pilot of a departing aircraft calls clearance delivery, states the aircraft identification and destination, and requests an IFR clearance.
The clearance delivery controller issues a clearance to the aircraft, providing the following elements:
- Clearance limit—typically the destination airport, but sometimes an intermediate fix.
- Departure procedure—tells the pilot on what heading and at what altitude to depart from the airport.
- Route of flight—the route that the pilot is to follow in order to arrive at the destination.
- Altitude data—the initial altitude to be flown and the altitude to expect at a specified time, typically 10 minutes, after departure.
- Departure control frequency—the first frequency on which to contact the departure controller when the tower instructs a frequency change.
- Transponder code—the code to be entered in the transponder to assist radai equipped air traffic controllers in following the aircraft.
While the clearance is being delivered, one of the flight crew members copies it down on a piece of paper so that it need not be committed to memory. The clearance is then read back to the clearance delivery controller to ensure that it was correctly recorded.
The method by which you copy the clearance is entirely up to you. There is, however, an accepted shorthand for recording ATC clearances. For example, a clearance and its corresponding shorthand for a flight from Pittsburgh to Atlanta follows:
"Lear 12345, Pittsburgh Clearance Delivery, cleared to the Atlanta Hartsfield Airport J53 J14; climb and maintain five thousand, expect flight level two one zero one zero minutes after departure, departure frequency one two four point seven five; squawk 4317."
C ATL A J53 J14 ↑ 50 EFC ↑ 210 10 < DEP PIT CT DP 124.75 SQ 4317
After having received a clearance, the pilot should prepare the cockpit for departure. The transponder (or "squawk") code should be entered in the transponder. The departure control frequency should be entered in the number two communication radio, which most real aircraft have. Navigation radios should be set to the appropriate frequencies and omni-bearing selectors turned to the appropriate courses to fly the initial route for which the aircraft has been cleared. It is far easier to accomplish these steps while the aircraft is still on the ground, rather than immediately after takeoff.
Either by computer or by hand, a flight progress strip is prepared for each aircraft flight. The strip prepared in the control tower contains the aircraft's route of flight, altitude, destination, transponder code, and other information.
Example: "Cessna N2001Z is cleared to the Newark International Airport as filed. After departure, fly runway heading, radar vectors to SWANN. Climb and maintain three thousand. Expect one six thousand one zero minutes after departure. Departure frequency one one niner point five. Squawk four three two six."