41–50 of 74 posts
Earlier quoted context omitted.
Easy enough to imagine. Something improperly was judged to not need concencus, running the calculation twice, or some other software mitigation. Revise process to include mitigation.
"just run the calculation twice. surely the darned solar radiation will take care not to hit random parts of the memory or any critical registers in the cpu"
Earlier quoted context omitted.
"just run the calculation twice. surely the darned solar radiation will take care not to hit random parts of the memory or any critical registers in the cpu"
What experience do you have with firmware that you're basing all this on?
The title sounds like speculative clickbait. From https://www.airbus.com/en/newsroom/press-releases/2025-11-ai... : Analysis of a recent event involving an A320 Family aircraft has revealed that intense solar radiation may corrupt data critical to the functioning of flight controls. This is different from the core claim that the incident was caused by radiation. What are the prior probabilities that the system was ex…
The title sounds like speculative clickbait. From https://www.airbus.com/en/newsroom/press-releases/2025-11-ai... : Analysis of a recent event involving an A320 Family aircraft has revealed that intense solar radiation may corrupt data critical to the functioning of flight controls. This is different from the core claim that the incident was caused by radiation. What are the prior probabilities that the system was ex…
My take was initially similar to yours but I have just updated it considering the affected units did not in fact have EDAC on them. With ECC, I would say the odds of having such an error decrease dramatically. But without it... yeah, I can believe it.
I can understand why this would be priority for Airbus even without the incident of a flight losing altitude - recently read that a major philosophical difference between Airbus and Boeing is that Airbus prioritises the safety of the Aircraft through controls (hardware and software) where as Boeing believes a human should always be the final decision maker and be able to over ride any control. An Airbus rarely allows…
Earlier quoted context omitted.
What experience do you have with firmware that you're basing all this on?
It's okay to not be nationalistic all of the time. Airbus will survive this extreme edge case. None of these comments matter in the bigger picture.
Earlier quoted context omitted.
My take was initially similar to yours but I have just updated it considering the affected units did not in fact have EDAC on them. With ECC, I would say the odds of having such an error decrease dramatically. But without it... yeah, I can believe it.
Where did you see that it didn't have ECC?
It was apparently added in a later HW revision
"The LTN-101 ADIRU’s CPU module was later redesigned to reduce costs and to include error detection and correction (EDAC). EDAC is used for detecting and correcting single-bit errors in RAM chips to give protection from single event effects (SEEs, see section 3.6.6). This change was a significant redesign and resulted in a new CPU module part number (466871-01). The EDAC was performed by a new ASIC, and all of the RAM chips used on the CPU module were replaced with a different chip.13"
https://www.atsb.gov.au/sites/default/files/media/3532398/ao...
Caused uncommanded pitch down, could exceed structural integrity of aircraft. There are redundant units - unknown why this can happen given redundancy.
Also not very clear how they attributed the failure to solar radiation.
[1] https://news.ycombinator.com/item?id=46083560
> On the Qantas 72 flight (2008), the ATSB report showed the same power spike that upset the ADIRU also left tidy 1-word corruptions in the flight data recorder. Those aligned with the clock cycle, shared the same amplitude and were confined to single ARINC words. That is pretty much exactly the signature of a failing solid state relay or contactor on the shared avionics power bus (upstream of both FDR and fly by wire).
> Radation-driven bit flips would be Poisson distributed in time and energy. So that is one way to find out