While generic flight plans can have a place in the preliminary trip planning process, it’s important to understand their limitations. Business jet operators should never use a generic flight plan to file a trip with Air Traffic Control (ATC) and should be aware that such flight plans only approximate aviation fuel burn and range capability over a given route and generic aircraft type.

1. Know what it means to use generic flight plans

A generic flight plan uses basic information provided by an original equipment manufacturer (OEM) and not information specific to your particular serial number. These flight plans may not take into account changes that have been made to an individual aircraft, such as additional fuel tanks, or after-market modifications, such as winglets or hush kits.

2. There are reasons for creating/providing generic flight plans

Generic aircraft information allows a flight planning system to compute a very basic flight plan. Two situations in which such flight plans are most often used include when operators want to compare different aircraft types they are considering purchasing or when operators are pre-planning a trip for aircraft they might not yet have. Additionally, generic flight plans are often generated for an operator’s training purposes.

3. General information used in generic flight plans

This information includes basic weights such as ramp weight; Maximum Takeoff Weight (MTOW); maximum landing; Basic Operating Weight (BOW); and basic navigation, communications and surveillance data to allow the system to run basic flight plan calculations. Generic flight plans typically factor in basic fuel reserves, although this may differ from individual operator standard operating procedures (SOPs) on fuel reserves.

4. Many types of information are not included on generic flight plans

Generic flight plans usually do not take into account:

• aircraft survival equipment
• aircraft weight
• fuel capacity
• navigation, communications and surveillance equipment
• capabilities specific to a particular serial number.

Other information missing from generic plans includes operator-specific fuel minimums, hold fuel calculations, fuel biases and other information specific to individual operators, such as extended twin engine operations (ETOPS).

5. Know limitations of generic flight plans

Flight plans using generic information differ from actual flight plans in several ways. An example is Reduced Vertical Separation Minima (RVSM). A generic flight plan can be generated based on RVSM capability. However, if the actual aircraft is not certified for RVSM flight levels, fuel burns will be different, and the generic flight plan will most likely not do the operator any good. Some aircraft modifications allow for greater takeoff weight or fuel load. In such cases, the generic fuel burns and range will most likely be inaccurate for the operator’s specific aircraft. As aircraft age, they tend not to perform to the numbers specified in aircraft flight manuals (AFMs) or pilot operating handbooks (POHs). Generic aircraft data does not take into account built-in fuel biases and, therefore, may overstate what may be possible in terms of range.

6. Never use generic data to file flight plans

Flight plans computed with generic data should be used for information purposes only and cannot be used to replace a specific flight plan. It’s important to ensure compliance with all information filed on a flight plan, as this impacts the safety of the flight. Recent changes to International Civil Aviation Organization (ICAO) DOC 4444 specify capabilities of equipment, crew qualifications and, when necessary, authorization from the appropriate authority. For example, you may have the equipment to meet RVSM requirements but not authorization from your state of registry. Or, you may be certified to fly required navigation performance authorization required (RNP AR) approach but have a co-pilot who does not meet the minimum requirements for that kind of operation. Filing a generic flight plan can result in a discrepancy in capabilities, so projected aviation fuel burns can be off.

7. Do not use information from another aircraft to run a flight plan

In many cases, an operator will have two aircraft with some similarities but different specifications. Due to those differences, adjustments will need to be made. Issues that may arise when using information from a different aircraft include inaccurate fuel burns due to required biases; fuel burn and weight calculations being off due to differences in BOW; and incorrect navigation, communications and surveillance capabilities (more prevalent with ICAO 2012 flight plan changes, which went into effect in November of 2012.)

8. Use information specific to the aircraft when filing flight plans

Always use information from the specific registry of the aircraft you’ll be flying when filing flight plans with Air Traffic Control (ATC). It’s important to keep your 3rd-party provider apprised of aircraft profile updates and changes. Keep in mind that flight plans are only as good as the data supplied to the 3rd-party provider. The closer the operator works with a 3rd-party provider, the better the quality of the flight plan. Best policy is to tailor a flight plan as closely as possible to the specific aircraft profile.

9. Generic flight plans have limited applications

It’s best practice to avoid using generic data when planning operational flights. As the regulatory environment (including the implementation that took place for ICAO 2012) continues to tighten, it will become more and more difficult to run generic flight plans. That is because flight planning systems will require additional information, such as onboard navigational equipment and capabilities, even to begin the process of creating a flight plan. Always coordinate with your 3rd-party provider when tweaking aircraft profiles in order to calculate more precise fuel burns and provide appropriate and required information to ATC. Also, always provide as much specific information as possible, upfront, to your 3rd-party provider.

10. Additional Reading

“Customizing Flight Plans – What Your Flight Department Needs to Know”

Conclusion

There are dangers in relying on generic flight plan data. Every aircraft is different, and the only accurate way to predict fuel burn and range is to provide as much specific information as possible to your 3rd-party provider. Avoid generic flight plans whenever possible. Best practice is to work closely with your 3rd-party provider so that all the specific characteristics of your particular aircraft are on file and updated on a continuing basis.

Questions?

If you have any questions about this article, contact me at jasondavidson@univ-wea.com.