Where No Error May Go

In a recent talk given to a large regional aviation group, we elaborated on the 3rd principle of Automation Airmanship – Data Entry – to some initial skepticism of the audience. It seems the general feeling that prevails among many flight crews is that wherever human operators are involved in data input, there we must also expect errors, and ultimately, some losses. It’s inevitable, after all, isn’t it?

We think not. We aren’t naïve in that we expect no errors to be made ever by the hands of human operators – but we do believe that they can and should be made under the broader protection provided by an uncompromising discipline that can be taught, practiced, and implemented in full view of every crewmember involved in flight deck activities.

There is not an individual in aviation that has not made an entry error when it comes to data input. From inputting incorrect performance data as a result of keystroke errors in FMS programming, to incorrectly tuning a communications or navigation radio, we have all made errors that were unintentional, some of which have gone unnoticed. We feel that diminishing these kinds of errors to near-zero levels is possible. That is, if we can perpetuate the idea that data entry be conducted in an environment that does not rely on the frailty of human memory, but instead counts on the durability of shared discipline.

Errors involving data entry in modern, advanced aircraft have become notorious over the past two decades and considered by many to be unavoidable hazards to be expected in aviation (an ASRS search conducted on any given day for reports containing the text “programming error” will turn up about 50 current NASA ASRS reports). American flight 965 (Cali, 1995), Emirates 407 (Melbourne, 2009), and more recently Virgin Australia 24 (Melbourne, 2013) are just a few examples of how data entry errors can have disastrous (or near disastrous) effects when allowed to persist. Most entry errors are like those mentioned in these examples (the kind that lead to undesired flight path excursions), which involve the incorrect entry of flight critical data – everything from an incorrect navaid entry, performance data, or waypoint information. In many instances crews have responded with a “Fly First” approach when a flight path deviation is noticed – but the concept is to prevent undetected data entry errors from requiring unanticipated (or even heroic) airmanship down the road.

Knowing what constitutes flight-critical data is the first step towards driving these errors to zero. Building a redundant, procedural “buffer” around the entry of this kind of information is the second and most important step. Flight critical data includes any data that directly or indirectly impacts the flight path of the aircraft contrary to crew intentions, the ATC clearance, or aircraft performance limits. Flight Critical Data includes waypoint information, waypoint constraints, navigation aids, altimeter settings including minimums, performance data, speed, roll or pitch commands via the FMS or flight guidance system are all on the list – along with other data that can be unique to an individual aircraft type or mission system.

It’s not hard to segregate flight-critical data from non-flight critical data – any flight department or flight standards group should be able to identify these without difficulty. Having done so, the vital second step is to implement strict and inviolable procedures that must be adhered to without compromise and without prejudice by every crewmember involved in flight operations. SOPs, Flight and Operations Manuals, Checklists, training and evaluation schemes must all be harmonized and carefully fit to the organization’s operational culture, configuration, and scale. A crewmember who completes FMS programming without a comprehensive check by another crewmember, a crew that relies on familiarity with one another to overcome data entry error, a crewmember who does not adhere to verification protocols 100% of the time – are all inviting the potential for entry error and possible disaster.

All of this is not to say that data entry cannot be improved by practice and proficiency at the individual level – but rather that policies and procedures can be improved to such an extent that flight critical data is never allowed to escape the uncompromising discipline of required redundant cross-checking and verification.

So much data is entered by crews during any given flight leg that it becomes nearly impossible to verify every keystroke; what is not impossible to do or unrealistic to expect is that procedures for checking entries are followed to a compliance level of 100%, on every flight leg.

Until our next report, fly safe, and always, fly first.

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