FORMATION FLIGHT.

FORMATION FLIGHT

- More than one aircraft which, by prior arrangement between the pilots, operate as a single aircraft with regard to navigation and position reporting. Separation between aircraft within the formation is the responsibility of the flight leader and the pilots of the other aircraft in the flight. This includes transition periods when aircraft within the formation are maneuvering to attain separation from each other to effect individual control and during join‐up and breakaway.

Source

FAA Pilot/Controller Glossary →

Related — General.

ACKNOWLEDGE ACKNOWLEDGE — Let me know that you have received and understood this message
ACROBATIC FLIGHT ACROBATIC FLIGHT
ACROBATIC FLIGHT [ICAO] ACROBATIC FLIGHT [ICAO]
ADMINISTRATOR ADMINISTRATOR
ADVISE INTENTIONS ADVISE INTENTIONS — Tell me what you plan to do
ADVISORY ADVISORY