But the point is, this reboot process is very well managed and known. So I won't call it scary.
The issue here is overflow due to time. The time is saved in a variable (don't know how much bits), which overflows after the gives period. Now there are two options 1. Upgrade circuits of every plane. These planes were designed/built a long time back. Bigger registers were not practical due to costs. 2. Document it and have a process for it.
In plane investigations I've looked at (not many) the issue has always been a compounding of several errors or shortcomings .. that strongly suggests you shouldn't let small errors build up in different systems, to me. [1]
If it's a register which takes down the whole system then surely they'd know that (and could fix it with a watchdog that returned the effected systems to the boot state without reboot) -- other comments seem to be saying "meh, it's complex, doesn't matter what the error is as long as reboot fixes it"; that seems really dangerous in safety critical systems.
[1] but I acknowledge the "better the devil you know" issue and that pragmatism and cost take over at some point.
I agree with that. But once you know about a specific big, there is always a solution.
> The remedy for the A350-941 problem is straightforward according to the AD: install Airbus software updates for a permanent cure, or switch the aeroplane off and on again.
Maybe the update process isn't streamlined enough, or maybe there are other reasons not to upgrade, but in general, the airlines need to install the updates.