Customizing Flight Planning Formats for ETP and FIR Boundary Information

PT 3 M minute read
Customizing Flight Planning Formats for ETP and FIR Boundary Information

Customizing Flight Planning Formats for ETP and FIR Boundary Information

This business aviation blog post continues from our previous article: Customizing Flight Plans – What Your Flight Department Needs to Know.

Equal time points (ETPs) and flight information region (FIR) boundary information are significant elements on your flight plan and warrant your attention when reviewing a flight plan format. The flight plan format should contain specific information and relevant calculations for ETPs, which are used when entering into regions where there are very few options for landing in the case of an emergency. FIRs are also important, as they depict the controlling agency of that region. Here’s what you should know about ETPs and FIRs in your flight plans:

1. What should be relevant information for ETPs on a format?

Since ETPs are critical during an emergency, and pilots will have their hands full flying the aircraft in such a situation, you want to ensure you have the necessary information to make the right decisions during the emergency. An ETP calculation should have a bare minimum of the following elements and calculations in the flight plan format:

  • The ICAO identifiers of the coast out and coast in alternates
  • An ETP description tells you what the emergency scenario is based on. For example, it may be a loss of an engine or a depressurization calculation.
  • The flight level the aircraft will be at when flying to the coast out or in alternates. This is particularly important if computing an engine out scenario because it gives you the level off altitude.
  • Waypoint coordinates of the ETP – This is the actual point where it is equal in time in returning or continuing to the coast out or in alternates
  • Distances – Make sure you have the distance to the ETP waypoint and distances to the coast out and in alternates
  • Time – The format should have the time to the ETP waypoint from the origin airport and the equal time to the coast out and in alternates
  • Fuel – You want a fuel burn from the origin airport to the ETP waypoint and the highest burn to the coast out and in alternates and at least a total “ETP fuel required” computation

2. Are ETPs standard on flight plans?

Yes. When flying oceanic routings and over more remote regions such as Africa, the Amazon, Siberia, and Northern Canada.

3. How should ETPs be displayed in flight plan formats?

This is a matter of crew preference. Some operators want ETPs displayed as waypoints in the body of the flight plan (leg portion), while others do not. However, formats should have a detailed summary of each ETP scenario, giving the crew vital and easy-to- understand information concerning those scenarios. Think about what scenarios you want to see on your format. The standard is a medical emergency at cruise altitude, loss of an engine, and a depressurization scenario. 3rd-party providers can put these summaries where preferred. Most are displayed after the flight plan or coded ICAO flight plan section at the bottom of the plan, in its own separate section.

4. Will inclusion of ETPs in the flight plan affect or interfere with FMS?

Providers should ensure that formats that are transmitted to datalink vendors, for uplink should be without ETP waypoint information. As long as the ETP waypoints are not sent to a datalink service, there is no problem with having them on your flight plan and they will not impact any uplink to the FMS.

5. What is an FIR?

A Flight Information Region (FIR) is a boundary between two different air traffic control authorities (also known as aircraft traffic control centers in the U.S.). A FIR is typically the upper region of this boundary. FIR boundaries are not to be confused with political boundaries (countries), as some FIR regions can cover several countries.

6. How are FIRs depicted on a flight plan format?

There are several options that a 3rd-party provider can offer in displaying FIR boundary information. Most formats have the FIR boundaries displayed in the body of the plan (leg portion) where they display the FIR identifier at the crossing. Providers can also display FIR boundaries as a summary, giving estimated time en route to the boundary, the boundary name, and the boundary identifier. FIR boundaries with estimated time en route (ETE) are always displayed on the FPL or coded ICAO flight plan – the portion that is transmitted to ATC.


Many options are available in selecting ETPs and FIRs and displaying them in the body of flight plan. Consider especially your ETP scenario options and what is realistic for your type of aircraft, and study the aviation regulations your operation must observe (if any) in oceanic emergencies and if there are ETP procedures or guidelines that should be reflected on a flight plan format.


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