Pre-Departure Clearance

Pre-Departure Clearance (PDC) is a method of delivering departure clearance via ACARS or private text message. It substitutes the conventional method of obtaining clearance over the frequency of Clearance Delivery to reduce communication and work required of aerodrome controllers. In the real world, PDC is performed from the data link system of the controller to the dispatch system of the airlines, which then relay the PDC to the flight deck crew via ACARS on the aircraft. This method was first used on VATSIM in 2008. On VATSIM, private text message is readily available which eliminates the need of installing a separate data link tool by the controller and an ACARS tool by the pilot. Hence, PDC is performed via private text messages within Hong Kong FIR. Owing to the growing amount of flight simulator add-ons that interface with the Hoppie network, the Hong Kong vACC also offers PDCs through the Hoppie network.

PDC reduces communication as well as expedite the flow of traffic by allowing clearance delivery the ability to issue more clearances in a given amount of time.

How does it differ from the conventional way of clearance delivery?

Once a pilot requests a PDC through private messages or through the Hoppie network, the on-duty Clearance Delivery controller will examine the flight plan. If the Clearance Delivery controller determines that the flight plan does not need modifications, a PDC will be issued to the pilot via private text message or through the Hoppie network.

Our PDC is broken into two parts which provide you as the pilot with all of the above information.

This PDC message serves directly as your clearance. Once you have received a PDC you do not need to perform a readback on any frequency. Once you are ready for push and start, you may contact the controller on the assigned frequency. If you do not receive a PDC, simply contact Clearance Delivery and request your clearance as normal.

The process of issuing PDCs should be a fairly quick process, but if it is busy it may take a few minutes. If you file a flight plan and call for clearance 5 seconds later, that will not leave the Clearance Delivery controller enough time to process and prepare your flight plan information into a clearance.

These PDCs can greatly reduce radio congestion on the clearance delivery frequency as well as issue clearances with greater efficiency and accuracy. Not to mention add a new level of realism to your simulation.