4 ms·

I think it's worth reporting on because this particular issue is known to everyone... you need to cycle the power on the planes every 3 days or else the reset t

I think it's worth reporting on because this particular issue is known to everyone... you need to cycle the power on the planes every 3 days or else the reset themselves. it's crazy that a modern plane needs to have that happen but it does. the most likely situation is that the plane didn't get shutdown and happened to occur at a level flying situation and the pilots probably freaked out and overflew the plane which got it into upset territory. the plane was trimmed and would have been fine if the pilots(likely) didn't do what they did.

thejazzman 3y ago
Unless you're a pilot I'm not sure why anyone would expect that to be common knowledge. And it's insane such a system would ever be authorized IMO. That sounds like a hack to fix a memory leak or similarly some bug they can't figure out
- inamberclad 3y ago
  I'm working on an aircraft program right now. We have a requirement to power cycle the plane every N days. It's in the manuals.
  - josephg 3y ago
    Why?
    - JumpCrisscross 3y ago
      > Why? Radiation-induced bit flips and bad code.
    - inamberclad 3y ago
      Simple: we have timer counters in the code. This is easier than handling them rolling over.
- mrguyorama 3y ago
  >Unless you're a pilot I'm not sure why anyone would expect that to be common knowledge. It should sure as hell be common knowledge to the pilots of the plane. I would have expected something like this to be on a checklist somewhere though: "Step 74, check uptime in Flight Computer, pull breaker if too high" Why would it be insane for a computer controller of what is essentially industrial machinery be designed to be reset at least once every other day? They "reboot" the engines damn near once a flight! Most pilots have experience and training on shutting down a plane for say overnight and then starting it from cold and dark the next day. It's an odd idea to us software developers but the computer isn't the primary function of the plane, and doesn't need to serve customers 24/7. If the computer is 100% reliable only for 18 hours, and the plane cannot fly for longer than 12 hours in the first place, is that a problem?
  - dotancohen 3y ago
    > If the computer is 100% reliable only for 18 hours, and the plane cannot fly for longer than 12 hours in the first place, is that a problem? It is a problem if it requires a human to remember to do the procedure, especially if it is not done on every flight. Putting it on the checklist, but making it optional per situation, is asking for someone to make a mistake. The reset should happen on every flight, if forgetting it on the wrong flight could potentially lead to an incident.
MadnessASAP 3y ago
There was a mandatory patch for that in 2020.
- l33tman 3y ago
  It apparently wasn't mandatory - you could ignore patching it if you kept doing the "reboot at least once every 22 days" directive from the AD 2016...
rootusrootus 3y ago
> you need to cycle the power on the planes every 3 days or else the reset themselves Huh? Try 51. https://news.ycombinator.com/item?id=33233827 https://news.ycombinator.com/item?id=33233827
- ceejayoz 3y ago
  Some A350s needed a reboot every 149 hours (6 days) for a while. https://gizmodo.com/turn-it-off-and-on-again-every-149-hours-is-a-concernin-1836818094 https://gizmodo.com/turn-it-off-and-on-again-every-149-hours...
devb 3y ago
> the most likely situation What is the value in posting a long, entirely speculative comment like this? It doesn't even appear that you have any credibility in this field. Even if you did, this comment would be useless.
tim333 3y ago
>pilots probably freaked out and overflew the plane I've got a pilots license and shoving the stick forward such that you pull negative Gs and passengers get stuck on the roof is not a normal reaction to the instuments going out. It sounds more like one of the computer systems crashed or lost power causing a lack of control until a backup kicked in, and caused the fly by wire to pitch downwards briefly.

thejazzman 3y ago

Unless you're a pilot I'm not sure why anyone would expect that to be common knowledge. And it's insane such a system would ever be authorized IMO. That sounds like a hack to fix a memory leak or similarly some bug they can't figure out

inamberclad 3y ago
I'm working on an aircraft program right now. We have a requirement to power cycle the plane every N days. It's in the manuals.
- josephg 3y ago
  Why?
  - JumpCrisscross 3y ago
    > Why? Radiation-induced bit flips and bad code.
  - inamberclad 3y ago
    Simple: we have timer counters in the code. This is easier than handling them rolling over.
mrguyorama 3y ago
>Unless you're a pilot I'm not sure why anyone would expect that to be common knowledge. It should sure as hell be common knowledge to the pilots of the plane. I would have expected something like this to be on a checklist somewhere though: "Step 74, check uptime in Flight Computer, pull breaker if too high" Why would it be insane for a computer controller of what is essentially industrial machinery be designed to be reset at least once every other day? They "reboot" the engines damn near once a flight! Most pilots have experience and training on shutting down a plane for say overnight and then starting it from cold and dark the next day. It's an odd idea to us software developers but the computer isn't the primary function of the plane, and doesn't need to serve customers 24/7. If the computer is 100% reliable only for 18 hours, and the plane cannot fly for longer than 12 hours in the first place, is that a problem?
- dotancohen 3y ago
  > If the computer is 100% reliable only for 18 hours, and the plane cannot fly for longer than 12 hours in the first place, is that a problem? It is a problem if it requires a human to remember to do the procedure, especially if it is not done on every flight. Putting it on the checklist, but making it optional per situation, is asking for someone to make a mistake. The reset should happen on every flight, if forgetting it on the wrong flight could potentially lead to an incident.

MadnessASAP 3y ago

There was a mandatory patch for that in 2020.

l33tman 3y ago
It apparently wasn't mandatory - you could ignore patching it if you kept doing the "reboot at least once every 22 days" directive from the AD 2016...

rootusrootus 3y ago

> you need to cycle the power on the planes every 3 days or else the reset themselves Huh? Try 51. https://news.ycombinator.com/item?id=33233827 https://news.ycombinator.com/item?id=33233827

ceejayoz 3y ago
Some A350s needed a reboot every 149 hours (6 days) for a while. https://gizmodo.com/turn-it-off-and-on-again-every-149-hours-is-a-concernin-1836818094 https://gizmodo.com/turn-it-off-and-on-again-every-149-hours...

devb 3y ago

> the most likely situation What is the value in posting a long, entirely speculative comment like this? It doesn't even appear that you have any credibility in this field. Even if you did, this comment would be useless.

tim333 3y ago

>pilots probably freaked out and overflew the plane I've got a pilots license and shoving the stick forward such that you pull negative Gs and passengers get stuck on the roof is not a normal reaction to the instuments going out. It sounds more like one of the computer systems crashed or lost power causing a lack of control until a backup kicked in, and caused the fly by wire to pitch downwards briefly.