Definition
The carriage of persons or property by aircraft, for compensation or hire, or the carriage of mail by aircraft, between any place in a State or possession of the United States and any other place in another State or possession, or between places within the same State through the airspace of any place outside that State. Defined under federal aviation regulations and used to determine which operations fall under federal commercial-operation rules.
Plain English
Flying people, cargo, or mail for pay across state lines — or between two points in the same state if the route passes through another state's airspace.
Context Anchor
Seen in aviation law, operating rules, air carrier discussions, and definitions that separate private flying from commercial public transportation.
Derivation
‘Interstate’ comes from the Latin inter (between) and state. So ‘interstate’ literally means ‘between states.’ This helps the aviation meaning: the flight crosses a state boundary, which is what brings it under federal commercial rules.
Why Pilots Care
Determines whether federal regulations and FAA oversight apply to the operation instead of state rules.
Intuition Check
Do not read this as “any flight between states.” In this context, it means a legally defined transportation operation, usually involving paid public carriage or mail carriage by aircraft.
Example Sentence 1
A charter flight carrying passengers for hire from Ohio to Kentucky is interstate air transportation and falls under Part 135.
Example Sentence 2
Federal economic regulations govern interstate air transportation even when the aircraft never leaves the contiguous United States.