Aviation Work-As-Done

Wrong take-off calculation!

Did you know that every time an aircraft takes off, it is based on the assumption that it will experience an engine failure?! That’s why pilots perform a detailed take-off calculation before each departure. This calculation used to be done using tabular data but is nowadays almost entirely replaced by software which enables input validation.

This software is updated daily as to include all obstacles present at and around airports worldwide. This means that if a crane is erected, the software takes into account any additional climb requirements to clear the crane in case of an engine failure. Obstacles affecting take-off calculations are included in the NOTAMs (Notices To AirMen), but since there are so many may be easily overlooked (“NOTAMs are just a pile of garbage“).

While software should actually help in doing the right thing, the interface of this particular Airbus (!) system shows the runway WITH an applicable NOTAM (22+1n) at the end of the list, which remains invisible to the pilot unless he actively scrolls down the list.

It is easy to miss this option resulting in insufficient climb performance in case of an engine failure.

Note: experts may argue that full power/thrust remains available at all times when using a FLEX take-off, but this is not the point. The problem here is that the interface actually introduces a hazard by showing the NOTAMmed runway last (far away from the original selection).

Solutions (systems thinking)

Why are both options (with and without NOTAM) still available? If only 1 option would remain it would be impossible to select the wrong one. If NOTAMs aren’t applicable all day (H24), consider filtering the list by time of day (with an override feature if needed). Either way, there should be a better way of displaying this list.