Here are 7 ways to get it done...

1) Leidos Flight Service - Phone

Formerly Lockheed Martin Flight Service, you can pick up an IFR clearance over the phone by calling 1-800-WX-BRIEF or 1-888-766-8267 (dedicated for IFR clearances).

2) Leidos Flight Service - Radio

You can, of course, try contacting flight service over the radio too. Locate the correct frequency in the chart supplement or on an airport chart. You might need to use a Remote Communications Outlet (RCO) or Ground Communications Outlet (GCO), that might have an associated voice-only/receive-only frequency using a VOR nearby.

3) Clearance Delivery

If you're flying out of a non-towered airport that underlies busy airspace, or is in the vicinity of an approach control, you might find a clearance delivery frequency listed on an airport chart or approach plate. If available, use this as your first choice for IFR clearances.

4) Approach Control

If an approach control facility frequency is available, you might contact them directly on the ground for an IFR clearance.

5) Air Route Traffic Control Center (ARTCC)

In remote areas away from approach control facilities, you can contact Center directly for an IFR clearance.

6) Relay Clearance

If all else fails and you don't have phone reception and can't pick up anyone on the radio, try contacting aircraft flying overhead for a relay clearance. ATC will have the flight crew relay you a departure clearance that you're expected to follow.

7) Depart VFR and obtain IFR clearance once airborne.

If weather conditions allow, departing VFR and picking up IFR in the air is preferable. If you depart IFR from a non-towered airport, you'll likely close down a large section of airspace for other IFR traffic arriving there. ATC must ensure the non-radar airspace is clear for your departure.

What's it like in real life?

Check out the video below to see what it's like getting an IFR clearance at a non-towered airport - both for airliners, and for GA pilots...

Have you ever had difficulty picking up a clearance? Tell us about it in the comments below.