If one of your gadgets doesn’t work as it’s supposed to, your first thought might be to try and turn it off and on again. That power cycle can fix some minor glitches. Now imagine doing that with a commercial airliner. It turns out that many airlines have to turn their Airbus A350 jets off and on again after every 149 hours due to a software bug.
This isn’t a new software bug. The first warning in this regard was issued by the EU Aviation Safety Agency two years ago. It stated that some models of the Airbus A350 had to be rebooted after exactly 149 hours.
The EASA has reissued a mandatory airworthiness directive this week which urgers airlines to turn their A350s off and on again in order to prevent “partial or total loss of some avionics systems or functions.”
Only the new A350-941s are exempted from this directive as they receive the patched software on the production line itself. Other A350-941s have to be completely powered down by the airlines and powered up again before the planes reach 149 hours of continuous power-on time.
Jets are routinely left powered on while they’re parked at airports so that engineers can carry out routine system checks. The remedy here for airlines is to install the software updates from Airbus to get rid of the problem or continue to reboot the plane after every 149 hours.