Before taking off on an IFR flight plan in the US, pilots must obtain a clearance from ATC.
A Pre-Departure Clearance (PDC) is an official text clearance. These clearances include important information such as the planned route, assigned altitude, transponder code, departure frequency, and any special instructions.
PDCs are often used by airline flight operations, especially at major airports, where airlines and pilots rely on streamlined procedures for IFR flight plans. It involves obtaining the IFR clearance electronically or through ACARS data link systems.
Normally, pilots will contact clearance delivery to request their IFR clearance. They use the CRAFT acronym to write down the clearance and then read it back to the controller. PDCs eliminate this process by allowing everything to be done through text. This means no more concerns about missing something during your CRAFT readback.
A PDC is equivalent to a verbal clearance from Clearance Delivery, but instead of a traditional clearance from air traffic control, pilots will receive a printed message or text via the datalink box in the aircraft, typically around 20 to 30 minutes prior to the filed departure time.
This method streamlines the process for aircraft carriers and ATC by having less vocal traffic on the comms.
PDCs are only offered at a limited number of major airports and come with specific guidelines for the types of aircraft that controllers will provide them to.
Pilots can receive a PDC by utilizing the built in aircraft avionics that rely on Hoppie as messaging network.
1. Pilot makes a logon request to the ATC unit.
2. ATC accepts logon request.
3. Pilot requests PDC.
4. ATC sends PDC.
5. Pilot will call ground control for push & start.
The PDC service delivers the clearance in a specified format, encompassing important elements such as the assigned transponder code, cleared altitude, and the active flight plan list.
While using PDCs instead of receiving verbal clearance from ATC can present some challenges, the main issue is often due to a lack of proper reading and comprehension on the part of the flight crew. It's important for them to carefully review any changes in the PDC before proceeding with their flight.
To avoid any issues with your pre-departure clearance, it's important not to assume that all the information listed is accurate. Take the time to verify and double-check for any errors.
If ATC gives you a different transponder code than what was stated in your PDC, don't hesitate to ask for clarification. Better safe than sorry!
Via Datalink (hoppie) in Aurora.
You'll receive the PDC 5-30 minutes before your planned departure time, and it will be valid for 2 hours after you take off.
No, after receiving your PDC, contact ground control.
ACARS stands for Aircraft Communications Addressing and Reporting.
PDC is what it's called in the United States. All PDC are done via CPDLC messages.
DCL is what it's called anywhere else (TELEX/ACARS message)