For the most accurate and operationally useful flight plans, it is important to be as specific as possible in terms of aircraft weights, performance, specific routings, speeds, and flight level requirements. To obtain the most accurate flight plan – in terms of operational efficiency and routings that will be accepted by ATC – work with an experienced 3rd-party provider in the flight planning, permit, and preferred routing requirements of all aviation authorities. Upfront planning and up-to-date aircraft information will result in the most efficient and trouble-free flight plan.

Here are some tips for best flight plan results:

1. Flight plan specifications should be given for each leg of a trip

The more specific you can be about your aircraft and routing requirements, the better and more accurate the flight plan. Always provide basic operating weight (BOW) when it differs from the standard weight, fuel load, passenger, and cargo weights, planned Mach speeds, and desired flight levels.

Speeds can be presented in Mach speed or a variable speed, such as Long Range Cruise (LRC) or Max Cruise Thrust (MCT). The speeds available will depend on the performance data provided by the aircraft manufacturer.

On average, passenger weight is assumed to be 200 lbs. per passenger unless otherwise specified. If there’s additional cargo to consider, this should be specified in order for the flight plan to be accurate and to avoid additional tech stop scenarios. Advise your 3rd-party provider of any onboard equipment changes, as this alters aircraft performance. Also, the age of the aircraft and condition of the engines plays a role in performance, so the biases should be reviewed and considered in order to receive a high-quality, accurate flight plan that can predict the performance of the aircraft.

2. Flight plans are only as good as the information provided

Best practice is to initially supply your 3rd-party provider with updated aircraft information, specifications, and biases in advance and to run test flight plans to validate predicted performance. Performance, aircraft age, equipment changes, and assorted biases will determine range capability and indicate accurate tech stop requirements. Also, communicate any relevant standard operating procedures (SOP) your flight department may have such as extended range twin engine operation (ETOP) requirements and or avoidance of certain country airspace, as this impacts flight planning, permits, estimated time enroute (ETE), and fuel requirements.

3. Consider flight plan delivery options

Even though some operators prefer flight plans to be delivered 12 – 24 hours in advance, it is better to receive them within at least 6 hours of the estimated time of departure (ETD), as wind conditions and forecasts will be more accurate. The primary reason for this is worldwide wind data comes out about every six hours. If a flight plan has to be delivered early – 12 or more hours pre-flight – the information may have changed, so it’s best to obtain a flight plan and weather update an hour or two prior to departure. Once you have the time of delivery scheduled with all of your updates set in place, the next step is to ensure delivery of that information. There are several delivery options available, which include e-mail, fax to the crew’s hotel and/or ground handler, and/or direct uplink to aircraft. Once the delivery selection is made, the crew should specify the time and method of delivery/communication and verify this information with their 3rd-party provider so there are no surprises.

4. Specify type of flight when requesting flight plans

Type of flight plan – private non-revenue or charter (non-scheduled commercial) – is important, as this will affect choice of alternates and crew duty availability. Also, how a flight plan is filed affects items such as permit requirements and fuel taxes. Charter flights should file “IN” commercial, due to regulation requirements and in order to exempt aviation fuel taxes when applicable. Filing a flight plan as commercial, however, impacts overflight and landing permit requirements.

5. Aircraft weight must be as accurate as possible

Basic Operating Weight (BOW), of course, is critical, as it affects the flight plan and alters fuel load and range. Changes in onboard equipment alter BOW. It’s important for your 3rd-party provider to be aware of these changes, particularly as ICAO 2012 became a reality in November 2012.

Knowing the weight of the aircraft is critical to your 3rd-party provider, due to the effects it has on aircraft performance in the flight planning process.

6. Consider optimized flight levels

Flight levels may be optimized in terms of taking the aircraft as high as it will go or in picking the best flight level for fuel burn. These preferences and objectives need to be specified from the beginning. Most flight levels specified by the captain can be filed, but the ultimate decision will be made by ATC. Requested flight levels may not be approved, and this happens frequently with Eurocontrol. It’s best to work with a 3rd-party provider that understands preferred routing and flight levels for each country in order to avoid flight plan filing problems. Consider flight level and routing nuances for various regions of the world. For example, China still uses metric flight levels, and there are areas of the world where ATC frequently keeps aircraft down below optimal flight levels. Also, India has many one-way airways, while Portugal bucks the trend in that odd flight levels are used north-south and even for south-north.

7. Consider pros and cons of specifying a route or having your 3rd-party provider build a route

When overflight permits are involved, it’s best to establish routings in advance, as flight plans may require specific airways. Last-minute routing changes may not be possible if permits can’t be revised in time. Some of the disadvantages of operator-specified routings include last-minute revision challenges based on winds, airways, temperatures, and permits involved. ATC has preferred routings, and it’s usually best to use them to avoid routing that may lead to route and/or permit rejections. 3rd-party providers specialize in building routes based on each country’s preferred routings and can assist operators avoid such flight planning issues.

8. Be specific in terms of the flight plan remarks section 18

In most cases, airport slots, Prior Permissions Required (PPRs), and permit confirmations need to be added to remarks section 18 to avoid ATC flight plan rejections. This is particularly important with more complex routings involving specific FIR entry and exit points. Additionally, border overflight exemptions (BOE) and TSA waivers should always be itemized in remarks section 18. This lets ATC know in advance if the aircraft can operate on the proposed routing.

Conclusion

When requesting flight plans, always be as specific as possible in terms of needs and requirements, including preferred flight levels, Mach speeds, and routings. Review aircraft specifications and weight at least once a year with your 3rd-party provider, and give them updated information for things such as aircraft BOW and equipment changes. Best practice is to obtain a flight plan and weather update anytime you receive your initial flight plan and weather 12 hours or more before ETD.

Questions?

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