Who has the clearance authority for IFR flight in uncontrolled airspace?

The correct answer is that the pilot in command has the clearance authority for IFR flight in uncontrolled airspace. In uncontrolled airspace, although air traffic control is not actively managing flights, the responsibility for safe flight operations falls to the pilot. The pilot in command must ensure that they are adhering to IFR procedures and are knowledgeable about the airspace they are operating in.

In uncontrolled airspace, while pilots should maintain communication with ATC when possible and follow proper procedures for IFR flight, ultimate authority and responsibility rest with the pilot. The pilot must evaluate weather conditions, ensure compliance with all applicable regulations, and determine their route of flight, thus ensuring safety and adherence to flight rules.

This authority allows the pilot to make real-time decisions regarding their flight path and necessary adjustments, while also being prepared to communicate with ATC if conditions change or if assistance is needed.