How to pick up an IFR clearance from uncontrolled airports?
Picking up an IFR clearance from controlled airports is pretty easy when ATC is operating. Just a quick call to ground control or clearance delivery will get you going. However, things may get a little bit complicated when there is no controller available to provide you with that clearance when the tower closes or when departing from a Non-Towered airport. The pilot can use several methods to obtain that clearance, and we will list them below.
On the ground
Flight Service Station (FSS)
The first option is to call flight service station over the radio. They will relay the request to the center or approach controller in charge of the airspace from which you are departing from. Flight Service station frequencies can be found on the low-level enroute chart or the chart supplement.
When the controller is ready to give you the IFR clearance, they will tell the briefer, and the briefer will relay the clearance back to you.
Clearance Delivery Number
The second option is to call a clearance delivery number that will communicate you with an approach controller or center controller that can provide you with your IFR clearance. This number can be obtained by calling flight service station by phone, listening to the AWOS from the departing airport, or looking at the chart supplement as shown in the image below.
In the Air
If the weather allows you to depart VFR, you can also try departing and calling approach control directly so they can provide your IFR clearance if their workload permits them. If not, they will advise you to reach the nearest FSS so they can relay the clearance to you. Pilots can also try reaching approach control directly on the ground by using the frequency found on the approach plates from their departing airport.
Clearance Void Time
Whenever a pilot is trying to obtain an IFR clearance from the ground in a Non-Towered airport, ATC has to protect the airspace from which that aircraft is departing until the plane is in radar contact and communicating with departure control. Therefore, anytime clearance is received from the ground, it will contain a void time that specifies the latest time the aircraft may depart. It will also include a time to reach ATC again if the pilots decided to delay their flight to avoid initiating search and rescue operations.
An example of an IFR clearacne contatining a void time sounds like this,
“N123EC is cleared to Tampa, via Radar Vectors to join the Miami Six Departure Winco Transition, climb and maintain 2000 and expect 8000 10min after departure, departure frequency is 125.5, squak 4343, enter controlled airspace heading 090°. Clearance void if not off to by 1700 Zulu, if not off by 1700 Zulu do not contact later than 1730 Zulu, time now 1640 Zulu“
In the example above, ATC gave the pilots a 20 min window to depart the airspace and contact departure. If they haven’t departed by 1730z, their responsibility is to reach ATC again to request a new void time or cancel their flight.
Don’t stop here, let’s keep learning!