Which of the following is NOT a method for filing an IFR flight plan?

• A. Online
• B. Telephone
• C. In person
• D. Satellite mail

Answer: (D)

When you file an IFR flight plan, you use channels that get the plan to air traffic facilities quickly and reliably. The standard ways are online through approved filing systems and by telephone with Flight Service, or you can file in person at a Flight Service Station. These methods provide real-time or near-real-time transmission and confirmation so controllers have your route, altitude, and departure details right away.

Satellite mail isn’t an accepted method for filing IFR flight plans. Mailing information via satellites would be slow and not suitable for the timely coordination needed with air traffic control. The filing channels are designed specifically for immediate processing, validation, and coordination before departure, which is why online, telephone, and in-person filing are used.