Yes, there are standards. The full Australian accident report finds that the 3 times in 29M flying hours that this issue occurred were within the standard (for

Yes, there are standards. The full Australian accident report finds that the 3 times in 29M flying hours that this issue occurred were within the standard (for a non-catastrophic issue, as they found this was). The systems did indeed cross-check, but there was an algorithmic edge case where the incorrect data was inappropriately used anyway, as happened here. It also did give control back to the pilots: after the second nose-down, the control law reverted as designed to 'alternate' (a degraded state) which removed the part of the envelope protection causing the nose downs. And the pilots also correctly switched to the backup ADIRU, which disconnected the faulty data from (most of) the aircraft's systems. For me, the interesting part of the article is the severe consequences for the pilot's mental health. A serious, but non-catastrophic problem occurs, and is skillfully dealt with by the crew (whose training is designed for exactly this). There are a number of injuries, but none are life-threatening. But the pilot's sense of responsibility, the feeling that it could all have been much worse, and a loss of faith in the aircraft, results in long term disability despite the 'successful' result.