Any aircraft operator who experiences an inflight emergency may land at any Air Force airfield without prior authorization (approved DD Form 2401 and 24 hours prior notice). An inflight emergency is defined as a situation that makes continued flight hazardous.

A private pilot can generally only land at a military airport under very specific circumstances: an emergency or with prior permission (PPR). In an emergency, a pilot is legally authorized to land anywhere necessary to ensure the safety of the flight, including an Air Force or Naval base. However, for non-emergency landings, a pilot must apply for a Civil Aircraft Landing Permit (CALP) well in advance. This is typically only granted if the pilot has a legitimate business reason, such as a government contract or a specific community event hosted by the base. Landing without permission at a restricted military installation—known as "busting" the airspace—will lead to an immediate interception by military aircraft, a forced grounding, and severe legal consequences from the FAA or relevant national authority. While some "joint-use" airports exist where civilian and military operations share a runway (like Charleston International or Eglin AFB), the military-only sections remain strictly off-limits to general aviation without explicit, written authorization and a valid "Prior Permission Required" number.