Definition
A flight plan filed for a VFR flight that will operate into, within, or across an Air Defense Identification Zone (ADIZ). The DVFR flight plan is required by national security regulations so that the flight can be identified and tracked while inside the ADIZ. It is filed with an FAA flight service facility before departure and includes the same basic information as a standard flight plan, with strict requirements for activation, position reporting, and adherence to the planned route and timing.
Plain English
A flight plan you must file when flying under VFR into or through a special airspace zone set up for national defense, so that controllers and the military know who you are and can tell you apart from unknown aircraft.
Context Anchor
Seen when planning a VFR flight that will enter or cross a U.S. coastal or domestic Air Defense Identification Zone.
Derivation
Defense refers to national defense; the flight plan exists so unknown aircraft entering sensitive airspace can be quickly distinguished from potential threats. VFR identifies the rules under which the flight is operated. Adding Defense to VFR signals that ordinary VFR rules still apply, but with extra identification requirements layered on top.
Why Pilots Care
Filing prevents military intercepts and keeps the flight legal in sensitive areas.
Intuition Check
Do not treat a DVFR Flight Plan as just an ordinary VFR flight plan. The “D” matters: it is used because the route involves an air defense identification area.
Example Sentence 1
Before departing the coastal airport, the pilot filed a DVFR flight plan because the route would cross the ADIZ within the first ten minutes of flight.
Example Sentence 2
Controllers used the DVFR flight plan data to confirm the aircraft was not a threat during the coastal route.