Clearance delivery is a ground-based ATC (Air Traffic Control) service that issues IFR (Instrument Flight Rules) route clearances to departing aircraft before they taxi.
How It Works#
At controlled airports, pilots contact the clearance delivery frequency before doing anything else. The controller reads out the aircraft's approved route, assigned altitude, departure frequency, and transponder squawk code. The pilot reads back every element to confirm.
The clearance itself follows a standard memory aid called CRAFT:
- C — Cleared to (destination)
- R — Route
- A — Altitude
- F — Frequency (departure)
- T — Transponder (squawk code)
At smaller airports without a dedicated clearance delivery position, ground control or the tower controller handles this function. At busy airports, clearance delivery is a separate position staffed by its own controller.
Clearance delivery also handles PDCs (Pre-Departure Clearances), which are digital clearances sent directly to an aircraft's datalink system. The pilot acknowledges the PDC electronically, reducing radio congestion.
Example in Aviation#
A pilot is departing Chicago O'Hare (KORD) on an IFR flight plan to Denver (KDEN). Before calling ground control, the pilot contacts clearance delivery on 135.400 MHz.
The controller responds: "Cessna 45 Juliet, cleared to Denver via the LEWKE departure, then as filed. Climb and maintain 5,000, expect FL230 ten minutes after departure. Departure frequency 124.0, squawk 4715." The pilot reads back each item in full. Once the controller confirms the readback is correct, the pilot is cleared and may contact ground for taxi.
Why It Matters#
Clearance delivery prevents costly and dangerous mistakes before a flight even leaves the ramp. Catching a routing error or wrong altitude on the ground is far easier than sorting it out in the air or on the runway.
For student pilots, this is often the first real radio call that feels high-pressure. Understanding the CRAFT format turns a wall of spoken information into a manageable checklist. Confidence here carries over to every other phase of the flight.
Key Takeaways#
- Clearance delivery issues IFR route clearances before taxi begins.
- The CRAFT acronym covers every element of a standard clearance.
- Always read back the full clearance; the controller must confirm it.
- At smaller airports, ground or tower may double as clearance delivery.
- PDCs deliver clearances digitally, cutting down radio workload.