The electronic flight bag and the planning apps
What the pilot remains responsible for when the charts, the weather and the flight plan all arrive on a tablet - and the specific ways these tools mislead.
11 min read · The IFR system and its rules
After this lesson you can
- State where responsibility sits when an EFB or a planning application is used.
- Name the limitations a pilot must know before trusting depicted information.
- Recognize information overload as a hazard rather than a feature.
- Plan for the failure of the device itself.
Electronic chart systems and electronic flight bags replaced a shelf of paper, and they replaced it with something that has a battery, a screen brightness, a subscription, and a legend the pilot may never have read. The instrument ACS asks about them three times - the limitations of electronic planning applications during cross-country planning, and the use of an EFB both as a knowledge item and as a risk.
None of the three asks whether to use one. They ask what you remain responsible for when you do.
1.Responsibility does not transfer to the device
The Pilot's Handbook of Aeronautical Knowledge states it as a bare rule: pilots remain responsible for the proper use of an electronic flight bag or installed avionics. It adds a practical consequence that instrument candidates should note - a pilot may be evaluated on the use and interpretation of an EFB or the installed avionics on the aircraft.
Two obligations follow. The first is the legend: pilots must be familiar with the content, format and meaning of the symbols and displays in the specific system they are using. A symbol set learned on one application does not carry over to another, and a moving map that shows something you cannot name is not information.
The second is provenance. Data integrity and limitations of use are the pilot's problem: the reliability of the depicted information, and any applicable disclaimer provided by the service provider. Weather delivered by a data link service is not the same product as the one the forecaster issued, and its age is rarely displayed as prominently as its colour.
Too much information is a hazard with a name
The handbook lists overload of information among the limitations. Most providers offer numerous products that layer on top of one another, and too much information can have a negative effect on cognitive workload. The remedy it gives is not to display less on principle but to manage the amount to the level that offers the most useful picture - which means deciding what to show before the flight, not during it.
2.Where planning applications go wrong
A planning application computes a route, a fuel burn and a time, and presents all three with the same confidence. The limitations that matter are structural rather than occasional.
The inputs are assumptions. A performance profile the application holds for the aircraft type is not the airplane you are flying, with its actual rigging, its actual engine and the drag of whatever is bolted to it. A winds-aloft forecast is a forecast. A fuel figure computed from both is a forecast built on an assumption.
The database has a currency date, and it expires quietly. An out-of-date navigation database does not announce itself with an error; it draws a fix where the fix used to be.
And the answer is confident regardless. An application asked for a route will produce one whether or not the airspace, the aircraft equipment and the pilot's ratings permit it. The check that the plan is legal and flyable remains with the pilot, and it is the check most easily skipped precisely because the output looks finished.
- Cross-check the number that matters — Fuel required, the alternate decision, and the minimum altitudes are worth confirming independently. A single-source answer to a life-limiting question is not a plan.
- Know what the app did not consider — It will not know about a NOTAM you did not fetch, an aircraft limitation you did not enter, or a currency requirement you do not meet.
3.The device is a single point of failure
A tablet fails in ways paper does not: it overheats on a sunlit glareshield, it dims to unreadable, it loses charge, it updates itself at the wrong moment, and it slides off a seat during turbulence at the moment the approach chart is needed.
Planning for that is part of using it. A charging source that works in flight, a backup for the charts you will actually need, and a habit of knowing the approach well enough to fly it if the screen goes black are the practical answers. The Airplane Flying Handbook makes the same point from a different direction when it discusses night operations: many charts can be displayed on an EFB, which does not require a separate light - convenient until it is the only light and the only chart.
The failure to plan for is not the dramatic one. It is the screen that stays on and shows something slightly out of date.
Quick check
A planning application returns a route, a fuel figure and an ETA for an IFR flight. What has it NOT established?
What to remember
- Pilots remain responsible for the proper use of an EFB or installed avionics, and may be evaluated on it.
- Know the legend: the content, format and meaning of symbols in the specific system being used.
- Know the provenance: data integrity, limitations of use, and the service provider's disclaimer.
- Overload of information is a named limitation - manage what is displayed, decided before the flight.
- Planning applications compute confidently from assumptions, and never check that the flight is legal.
- The device fails; the backup for the charts and the knowledge of the approach are part of using one.
Key terms
Try to recall each definition before turning the card.
FAA sources for this lesson
- PHAK FAA-H-8083-25C - Use of equipment and avionics display; data integrity and limitations; overload of information
- IFH FAA-H-8083-15B Chapter 1 - Electronic chart systems and electronic flight bags
- AFH FAA-H-8083-3C Chapter 11 - Charts displayed on an EFB at night
- FAA-S-ACS-8C Area I Task C and Area II Task B - Electronic planning applications and EFB use
End-of-lesson quiz
1.According to the PHAK, who is responsible for the proper use of an EFB?
2.Which of these is listed by the handbook as a limitation of these systems?
3.What is the most structural limitation of a flight planning application?