Who is responsible for separation between aircraft within a formation?

The flight leader and individual pilots are responsible for separation between aircraft within a formation because formation flying requires close coordination and communication among all aircraft involved. In this context, the flight leader has the primary role in establishing and maintaining the flight's position and ensuring safety; however, all pilots in the formation also share the responsibility for maintaining separation. Each pilot needs to remain vigilant and follow the flight leader's commands while also being aware of the positions and movements of other aircraft in the formation. This teamwork ensures that the formation can operate effectively without compromising safety.

In contrast, designating the flight leader alone as the sole responsible party for separation does not account for the collective responsibility that is necessary in formation flying. Relying solely on ATC for separation (as suggested in the other option) would disregard the unique nature of formation operations, where pilots must actively manage their distances and maneuvers. Supporting vehicles are not involved in the separation of aircraft within a flight formation; their roles are distinct and cover other aspects of operations, such as logistical support on the ground.