We're (more or less every western civilization) going to have trouble funding UBI for seniors who can't work even if they wanted to; never mind UBI for working age populations.
This comment is a tangential distraction, but it's not even correct. Linus Torvalds has specifically claimed that he wouldn't have created Linux at all if 386BSD was available at the time. But BSD was tied up in a lawsuit with USL, discouraging companies and individuals from use.
This has been discussed ad nauseam and this adds nothing new. There's value in the memory safety for the majority of the code even if there are some escape valves ("unsafe" keyword, assembly).
The Nasdaq 17 year figure is only true from the peakiest peak of ~4800 in March 2000. Two years earlier, in March 1998, it was at 1750. It had hit 1750 again by August 2023.
All this to say... shorting 1-2 years early doesn't work. You don't have the patience or capital to actually maintain a short position for two years while the market goes from 1750 to 4800. You can cheaply sit out in cash, if you want, but that's not a short position. And the S&P500 hasn't seen the kind of 300% run-up over an 18 month period that Nasdaq did in the dotcom boom.
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
Do you think they're using the guise of "its solar radiation" as cover to do a software update to fix a more problematic "bug", and perhaps tangentially there are some changes in said-update to improve some error correcting type code (eg: related to detecting spurious bit flips).
I would say its pretty detailed -an unknown interference caused a single crc protected 32 bit word to be corrupted simultaneously, by timestamp, in both the flight controller hardware and the black box data recorder.
My concern would be what error correction mechanism did or did not catch the corruption in memory and why did it not recover without critical impact to operations?
Reading the Airbus press release, I wonder if this is what happened:
Solar radiation event led to alpha particle induced data corruption in a flight control computer memory (could be DRAM, SRAM, on-chip cache, registers...). These failures are supposed to be transient (reboot and all is well).
This is an anticipated failure mode. Only one (of three?) computers should be affected by such a failure and therefore the remaining two keep on running the plane.
But what happened is <something> went wrong with the failover/voting mechanism (as often happens with one-off seldom-executed failover code). The result was no flight control computer functionality until the entire system was rebooted. Hence the emergency landing.
The fix is to address that software error, with perhaps a secondary fix TBD to harden the hardware (add some shielding perhaps).
The fact that they talk about data corruption and not just a malfunction suggests alpha bit flip rather than latch-up.
Then send the whole statement through a French to English translator to make it a bit more confusing.
After reset, it went away. If it was this kind of hw issue, it should still be present.
Considering those units were designed back when they did not have EDAC mandated, I can believe it could have been a bit flip (along with some other stuff they will probably address to take into consideration this failure mode). Nowadays, most MCU's have ECC on them so the time of this excuse is mostly gone now. :)
> Nowadays, most MCU's have ECC on them so the time of this excuse is mostly gone now. :)
That's kind of a misleading statement. Assuming you mean on planes built nowadays, as we clearly see that nowadays planes still flying (6K of them at least) still have issues. We don't need hand wavy comments trying to make it sound like modern day aviation is no longer susceptible, especially when it's in a thread on an article showing how that's just not true
I think you and gp may be speaking about different stages. Gp seems to be saying that a plane being designed and specified today would use technologies hardened against this type of error.
That even though they’re in widespread operation today, the aircraft types in question were designed (and certified) many years ago, before ECC was the norm. My impression is that, once their type is certified, new airframes are built to pretty much exactly that specification even all these years later.
> I think you and gp may be speaking about different stages
Yes, that's my point. Just because new aircraft are designed with improved hardware does not automatically mean the issue is resolved industry wide. Existing equipment will still have issues. So the statement is misleading. Is the number of aircraft with ECC "most" of the equipment in the skies?
Ok, I can see how my statement can be confusing. I wanted to say that on newly built things this is mostly gone today, although I'm certain freakish accidents can happen. Yes, if your hardware does not have ECC[1] that is something that can happen. I was initially surprised because I did not expect them to not have error correction, but I guess it makes sense for systems designed a long time ago and still in use, so that was new info to me.
[1] Technically EDAC is the correct name of the whole sybsystem, and ECC is the name of the algorithm. But I've only heard it refered as ECC in my industry. I was even initially confused when I read EDAC, so TIL.
"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)."
To give you a bit of insight, around the same timeframe (late October/early November) I directly observed two high-accuracy RTK GPS receivers reporting high accuracy (2cm), full 3D DGPS lock with carrier phase, and positions wandering within about a 5m circle horizontally. The altitude was staying pretty consistent (within about 1m, which was outside of the reported accuracy but not bad) until there was a sudden 60m altitude shift. This was all while they were sitting static on the ground, verified both by the crew and the accelerometer, gyro, and RADAR data.
There wasn’t a software fix per se, but we were able to quickly add a check to verify that the Kalman Filter’s position variance estimate was on the same order of magnitude as the accuracy level that the receivers were reporting and put a big red warning up. This wasn’t a flight-critical system, but it is the first time we’d ever seen that behaviour from those receivers and we’ve used them for 5 years.
i would expect a huge shift like that to violate the gaussian assumption of the kalman filter? (which i guess is what you're checking, sort of?). regardless i would expect the kalman filter to smooth the shift over some substantial time at least?
i wonder how definitive that is and how well they were able to reproduce the issue under controlled conditions and how strong the evidence is that there was particularly strong solar radiation in play. it would probably be a good thing if they published technical details for investigations like this that impact public safety.
i believe it could be solar radiation, but i also believe that solar radiation could be a catch-all for unexplained phenomena.
Note that the software update (it actually looks like a roll-back to an older version?) will only fix 4,500 newer aircraft, another older 2,000 (not sure what these are, they can't be pre-NEO, the ratios seem wrong?) will also need a hardware fix.
I'm amazed airlines haven't put up press releases detailing what is happening with their fleets yet. It has been a few hours so presumably they know and in the US at least this is a crazy busy weekend for travel.
Unless they had total component failure, its most likely localized and if you create redundancy like RAID - you may be able to counter whatever they are seeing as a failure mode. Or at least reduce the likelihood of impact on the flight giving them time to replace components on the ground
Parent comment is begging you to understand that correlation is not causation. That you infer it to imply causation leaves you less well-informed about the world.
Well, rockets are even worse, of course. :)
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