This story could make a good anecdote to remember when considering human factors, user interface, and checklist design.

> Investigators said that because the pilots flew the second circuit at 1500ft, the Electronic Centralised Aircraft Monitor (ECAM) had not reset on the second approach and it did not display a landing memo at 950ft.

“The absence of the landing memo should have prompted the flight crew to perform the items of the landing checklist as a ‘read-and-do’ checklist,” it said.

Like the lock icon in a browser’s address bar, it is not effective to rely on the user to notice the absence of an indicator.