Learn what a flight plan is, what it contains, when pilots file one, and how it differs from an ATC clearance, navigation log or GPS route.
In aviation, a flight plan is a structured record of an intended flight, covering aircraft identity and type, departure and destination, estimated times, route, altitude, speed, fuel endurance and people aboard. Pilots or dispatchers prepare it for safe planning; when filed, air traffic services use it for traffic handling, coordination and alerting.
What information does a flight plan contain?
A filed flight plan tells air traffic services who is flying, where the aircraft intends to go and how the flight is expected to operate.
- Aircraft details: registration or callsign, aircraft type, wake-turbulence category and onboard communication, navigation and surveillance equipment.
- Departure details: departure aerodrome, estimated off-block time and, when necessary, the location from which the flight will begin.
- Flight rules and route: IFR or VFR status, cruising speed, planned level, waypoints, airways and relevant departure or arrival procedures.
- Destination details: destination, estimated elapsed time and alternate aerodromes.
- Supplementary information: fuel endurance, people aboard and available emergency or survival equipment.
The exact fields and filing rules vary by country, type of operation and airspace. An airline plan is also far more detailed than the short route displayed on a cockpit GPS.
The records people often call a flight plan
In everyday aviation, the term can refer to several related records that are not interchangeable.
| Record | Purpose |
|---|---|
| ATS flight plan | Standardised information filed with air traffic services for control, flight information, coordination and alerting. |
| Operational flight plan | The crew's working plan, often including weather, fuel calculations, weights, alternates, performance data and operational remarks. |
| Navigation log | A detailed record of headings, distances, times, winds, fuel estimates and visual or radio checkpoints. |
| FMS or GPS route | The sequence of waypoints and procedures entered into the aircraft's avionics for navigation. |
These records may contain the same route, but creating one does not automatically create the others. Our explanation of how dispatchers and pilots prepare and use an airline flight plan covers the fuller operational process.
Is a filed flight plan the same as an ATC clearance?
No. A flight plan states the pilot's intentions, while an ATC clearance authorises the aircraft to operate under specified conditions.
ATC may clear the filed route, replace part of it, assign a different altitude or issue vectors after departure. The phrase “cleared as filed” means the filed route has been accepted without needing to read every waypoint aloud; it does not remove the other limits and instructions in the clearance.
Filing also does not always mean that a plan is active. Depending on the flight rules and local system, the plan may need to be activated or opened when the flight begins. Plans used for alerting must also be closed or cancelled when required, otherwise overdue-aircraft procedures may start.
Does every flight need a flight plan?
No; the legal requirement depends on the jurisdiction, flight rules, route and airspace involved.
Operating under IFR commonly requires an appropriate flight plan and ATC clearance. A local VFR flight may not require a filed plan, although filing can provide valuable alerting and search-and-rescue information. International flights, particular routes and certain classes of airspace can introduce additional requirements.
Not having to file a plan does not remove the need to plan the flight. The pilot still needs to assess weather, fuel, airspace, aircraft performance, alternates and diversion options. Our guide to building a practical VFR cross-country plan explains that distinction.
A VFR flight plan also does not normally provide traffic separation or flight following by itself. It primarily records the intended flight and supports alerting if the aircraft becomes overdue.
What does a flight plan mean in a flight simulator?
In a flight simulator, a flight plan usually means a route created in the simulator's planner or loaded into the aircraft's GPS or flight-management system.
A mistake we see constantly is assuming that these are automatically synchronised. Depending on the simulator and aircraft add-on, the world-map route, cockpit avionics and built-in ATC may hold separate versions of the plan. Editing one may not update the others.
Loading a route into the avionics also does not necessarily file it with simulated ATC. Our guide to the relationship between simulator ATC and filed plans explains when a plan is actually needed. Likewise, an autopilot will not follow the route merely because it is visible on the map; the correct navigation source, active leg and lateral mode must be selected, as covered in our autopilot route-tracking guidance.
The useful distinction is simple: planning decides how the flight can be conducted safely, the flight plan records that intention, filing shares it with air traffic services, a clearance states what ATC authorises, and the avionics route guides the aircraft.