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> Reboot every 51 days or risk the pilots getting wrong airspeed indicators If this is documented then fair enough - airlines don’t have to buy airplanes that

by Nextgrid 11mo ago

> Reboot every 51 days or risk the pilots getting wrong airspeed indicators If this is documented then fair enough - airlines don’t have to buy airplanes that need rebooting every 51 days, they can vote with their wallets and Boeing is welcome to fix it. If not documented, I hope regulators enforced penalties high enough to force Boeing to get their stuff together. Either way, the uptime of avionics (and redundancies - including the unreliable airspeed checklists) are much higher than anything conventional software “engineering” has been putting out the past decade.

mschuster91 11mo ago
Personally, I'm of the opinion that either of these three defects should not ever have been possible in the first place, that should have been prevented by formal verification. If some dingus widget provider has a downtime, no one dies. If an airplane loses power mid flight due to a software error... that's not guaranteed any more.
- cadamsdotcom 11mo ago
  The requirement to reboot is documented, and it’s an order of magnitude away from being a regular problem - ie. 51 days instead of every 51 minutes. This puts it in the same maintenance bucket as parts that need regular replacement. To use the “part needing regular replacement” analogy - the bug could be fixed for an extra $Y. But everything in engineering is a trade off. Choosing not to fix the bug might bring costs down to something competitive with the market. Plus, like any part that could be made more reliable for extra cost, there might be no benefit due to service schedules. Say you could design a part that is 60% worn at service time vs a cheaper part that’s 90% worn - it they will both need replacing at the same time, you’d go for the lower cost design. Eg. if some service task requires resetting the avionics every 40 days, that’s less than 51 days so there may as well be no bug.

mschuster91 11mo ago

Personally, I'm of the opinion that either of these three defects should not ever have been possible in the first place, that should have been prevented by formal verification. If some dingus widget provider has a downtime, no one dies. If an airplane loses power mid flight due to a software error... that's not guaranteed any more.

cadamsdotcom 11mo ago
The requirement to reboot is documented, and it’s an order of magnitude away from being a regular problem - ie. 51 days instead of every 51 minutes. This puts it in the same maintenance bucket as parts that need regular replacement. To use the “part needing regular replacement” analogy - the bug could be fixed for an extra $Y. But everything in engineering is a trade off. Choosing not to fix the bug might bring costs down to something competitive with the market. Plus, like any part that could be made more reliable for extra cost, there might be no benefit due to service schedules. Say you could design a part that is 60% worn at service time vs a cheaper part that’s 90% worn - it they will both need replacing at the same time, you’d go for the lower cost design. Eg. if some service task requires resetting the avionics every 40 days, that’s less than 51 days so there may as well be no bug.