This business aviation blog post is part of a series on filing flight plans, their validity, and revisions.

The process of filing and revising flight plans, as well as the validity periods of flight plans, differs by country. For some locations and regions this information may be more difficult to obtain. For destinations outside your home country/region, it’s often best to work with your 3rd-party provider and/or local ground handler to ensure flight plans are filed correctly.

The following is an overview of what you need to know:

1. Filing flight plans

In general, a flight plan (FPL) should be filed at least one hour prior to the estimated time of departure (ETD), unless different lead time guidelines are provided by the local governing authority. Within the U.S. a FPL is accepted up to 23 hours in advance and will remain in the system up until two hours past the filed estimated time of departure (ETD). In Europe a FPL may be filed up to a 120 hours (ICAO standard) prior to ETD and remain in the system for two hours. If the FPL is not activated within 15 minutes of ETD, the FPL will be issued a Flight Suspension Message (FLS).

2. Filing process

Most countries publish flight plan filing information in their aeronautical information publication (AIP). Many countries are working towards automating the filing process and over the past few years countries such as Singapore, Thailand and Bahrain have added automation to their filing process that includes feedback to the FPL originator in the form of Acknowledgement (ACK) and Rejection (REJ) messages. In cases where flight plan information is not readily available contact your 3rd-party provider.

3. Standard filing methods for flight plan filing

Flight plans are filed via aeronautical fixed telecommunication network (AFTN). With working through a 3rd-party provider or a do-it-yourself flight planning system, this is most likely the filing method being used. Alternatively, you can file through a ground handler or local air traffic control (ATC) office–in some cases literally handing off physical paperwork. Some countries, such as Malawi and Argentina, require crew to be present at the ATC office in order to file flight plans. Unfortunately, it’s not possible to file flight plans via email directly with ATC.

4. When to file

Every country will have different requirements as to how far in advance a FPL can be filed and what the minimum requirement to file is. The ICAO standard is to allow a FPL to be filed up to 120 hours prior to ETD. Many countries (such as the U.S.) only allow a FPL to be filed a max of 23 hours in advance. The majority of countries require a FPL to be filed a minimum of one hour, if not more in advance of ETD. Best practice is to use a 3rd-party provider, well acquainted with the flight plan filing processes, to avoid possible delays and/or flight plan cancellation.

5. Short notice flight plans

Short notice flight plan filings can potentially cause delays. In areas with Air Traffic Flow Management (ATFM) programs, filing as soon as possible allows your flight to receive a higher priority when air traffic control (ATC) needs to impose traffic management measures against flights. Making changes to your FPL or filing at the last minute will potentially put your flight at the bottom of the priority list. If you’re filing an FPL in a country that requires it to be processed by a local office, you can expect your ETD to be delayed to the minimum required filing time.

6. Delayed flight plans

If you are in a position that requires a delay to your initially scheduled departure time and this delay is less than 30 minutes, the best practice is to contact ATC directly and tactically work out the delay with them. If the delay is 30 minutes or more, then either work with the local handler or your filing service where a Delay Message (DLA) can be sent to ATC alerting them of the new departure time. ICAO standard practice is to only send a DLA message if the delay is greater than 30 minutes from the currently filed ETD.

7. Eurocontrol considerations

Eurocontrol’s website allows operators to submit a planned route into the system to check for errors and to verify flight plans. Eurocontrol has two sites – one public and one for operators/providers that have an account with Eurocontrol. The website requiring the Eurocontrol account provides additional information when flight plans are loaded, to better determine validity.

Conclusion

The most common errors in filing a FPL has to do with incorrect routings and aircraft codes. It’s recommended that you communicate with your 3rd-party provider that will assist in verifying validity of proposed flight plan filings.

Questions?

If you have any questions about this article or would like assistance filing your flight plans, contact me at jasondavidson@univ-wea.com.

Stay tuned for Part 2, which covers tips and considerations when filing flight plans.