Possible Clues:

• Broadcasts from March in an out-of-this-world setting - typical of a pilot
• A country's flying region
• Part of a nation's sovereignty
• It is protected by military planes
• Where one sees jumbo reveals speed?
• What's over one's head? Hat's upside down in Yorkshire river!
• Broadcast at the start of 26 across from the flight zone
• Pilot's zone that may be restricted
• It's under and over a country's jurisdiction
• It's under a country's jurisdiction, though over it