Alaska 737 cockpit voice recorder data erasure renews industry safety debate
Alaska 737 cockpit voice recorder data erasure renews industry safety debate
By Valerie Insinna, David Shepardson and Lisa Barrington
The cockpit voice recorder data on the Alaska Airlines Boeing 737 MAX 9 jet which lost a panel mid-flight on Friday was overwritten, U.S. authorities said, renewing attention on an industry call for longer in-flight recordings.
National Transportation Safety Board (NTSB) chair Jennifer Homendy said on Sunday no data was available on the cockpit voice recorder because it was not retrieved within two hours - when recording restarts, erasing previous data.
The U.S. requires cockpit voice recorders to log two hours of data versus 25 hours in Europe for planes made after 2021.
The International Civil Aviation Organization (ICAO) has since 2016 called for 25-hour recording on planes manufactured from 2021.
"There was a lot going on, on the flight deck and on the plane. It's a very chaotic event. The circuit breaker for the CVR (cockpit voice recorder) was not pulled. The maintenance team went out to get it, but it was right at about the two-hour mark," Homendy said.
The NTSB has been vocal in calling for the U.S. to extend its rule to 25 hours. The U.S. Federal Aviation Administration (FAA) a month ago said it was proposing to extend to 25 hours – but only for new aircraft.
Why the fuck would they have only hours of recording? Even my cheap voice recorder can go for hundreds of hours
An example of a corporation doing the bare minimum required by law.
Laws which they've lobbied and used regulatory capture to slow any updates.
Regulations are important.
These regulations were written a long time ago when physical tape was used. Boeing has since captured the American regulatory system.
To be entirely fair your cheap voice recorder is not expected to also survive a plane crash. That being said European planes have more without issue so yeah.
This isn't entirely an excuse, but a CVR has some pretty serious durability requirements. They're required to withstand physical forces, sustained exposure to direct flame, lengthy submersion in sea water...it's not a trivial device.
On top of all that, you have to factor in the development and testing costs for the CVR or FDR too. These are usually off the shelf, previously developed components. A seemingly trivial change like bigger storage suddenly costs several hundred thousand dollars to retest and time to recertify by dozens with agencies around the world. If the regulations have not changed, then there is no reason for to go through that whole R&D process again when the same bought and paid for system works.
To be fair, your voice recorder probably can't withstand being slammed into the ground at 500mph...:P
Even my cheap voice recorder can go for hundreds of hours
Only marginally related, but I run into this a lot with "Why can't I have more space in my homedir? I can go buy a disk from BestBuy and it's only $50." The two products - a TEAM disk from BB and the media approved for enterprise (let alone emergency/recovery) work are from two different worlds.
Probably when these regulations were put in place in the 1960s or whenever, there were technical limitations on these recording devices.
Yeah that’s pretty goddamned short. If you can only record two hours you’d better not have flights longer than that.
Flight recorders have a very long history with modern ones being engineered in the 1960s. They used film and magnetic tape loops, having very limited capacity. That's where we get 2 hours from. Early ones only ran for 30 minutes, so 2 hours is pretty good in comparison.
It's time to upgrade the regulations to match our current technology instead of 1990s limitations.
No surprise here since Boeing owns the FAA.
The reason the 737 has been redesigned and retooled and extended so many times is that certifying an entirely new airframe with the FAA is a wildly expensive and time consuming process. I'm not denying that Boeing has a lot of influence, but they clearly don't own the organization that has been such a pain in their ass in the first place.
I assume you meant 737.
Not just that, but all the tooling and manufacturing space needed is insanely expensive. The max mostly just needed tooling for the nacelles/pylons.
I understand that there are definitely some limitations in CVR due to durability requirements, but given the capabilities we have today for very tiny immense storage of audio recordings, I don't see any reason the US shouldn't at the minimum match the european standard of 25 hours. Not only that, but find a way to retrofit the new CVRs into older airframes.
But the price of memory is due to go up again!
Again? I forgot about that
Don't get distracted by shiny objects and squirrels here folks. Boeing should be the focus here.
Eh, why not both? The airplane is a BIG problem, but this is a big issue too that should not be overlooked because we have another problem...
2 hours? What the fuck?
Because if you crash you only need to review the immediate events leading up to a crash. 2 hours is generally plenty. If a plane is hijacked and then crashed, you don’t need 5 or 10 hours of voice to know what caused the crash.
The point of the CVR was to find out what went wrong or what errors happened leading up to a catastrophe, not what the pilots had for breakfast 5 flights prior.
Thats not really true at leat according to aircrash investigation shows. Crew can make mistakes hours earlier that might lead to a crash or accident later. Mess up something during preflight checks and that can be the issue during later stage. Flights are long.
But with modern datastorage prices there's really no excuse not to make it longer. With 15GB you can store 24 hours of extremely high quality audio.
because it was not retrieved within two hours - when recording restarts, erasing previous data.
OK, I agree it should be longer. We are no longer limited to magnetic tape spools. But once the aircraft is parked and shut down, why not stop the recording without having to pull a circuit breaker?
I'm just guessing, but if the plane suddenly decided it's parked and shut down while it's actually in the air ...
We might want that recording.It would take a metric buttload of things going wrong for that condition to happen. There are a lot of sensors tied to detecting that the aircraft is on the ground, and the system fails safe in air mode.
I feel like I'm saying this on an almost weekly occurrence:
McDonnel-Douglas ruined Boeing.Aside from that, it's more appropriate to call them McBoeing these days.
Do please elaborate, or give some pointers. Am unfamiliar with the background.
Until their Air Force One, or any of their other defense products start being produced the way they produce aircraft that the general public uses, we will continue to be the guinea pigs to see how much regulation can be stripped away for profit margins until we start to die at rates that become unprofitable for them. Industry never really learned from the Triangle Shirtwaste Fire and safety regulations will continue to be written in blood because ALL legislators would rather take donations and shut up than challenge a component of the MIC.
Yeah so that has already happened with the KC-46 the pentagon quit accepting deliveries twice
https://www.aerotime.aero/articles/28229-How-KC-46-Pegasus-became-another-737-MAX
You’re clearly referring to train derailments. Oh wait…
Give Boeing a choice- retain 25 hours of flight records, or pay a billion dollars for every incident where the data is requested but was destroyed to save disk space that costs about nothing to keep
What's the reason for not doing 25 hours in this day and age? It's not physical media, right? Digital storage is cheap.
Boeing doesn't have to fulfill that requirement. The CVR manufacturers will. Most likely it's Honeywell or L3. Boeing will just have to install upgraded CVRs on new aircraft, while airlines will need to update if the FAA ever gets around to updating the requirements.
Ugh boeing should just be nationalized. I don't trust them to go above and beyond in safety anymore. I will be purposely trying to fly Airbus if I have the option.
I am a little surprised there isn't a catastrophic "save last 5 minutes" type thing like with a dashcam. I guess in many cases that last 5 minutes would have been saved by the fact that it crashed, but the issue was overlooked for planes that suffer a major event and stay in the air.
In this case, I seriously doubt the pilots' conversation is going to add much to the investigation. It seems pretty obvious what happened and outside the pilots' control.
My cheap dashcam does rolling saves if days worth of HD video... but aviation safety can only manage 2 hours of audio? Weeks worth of buffer should be trivial to add from both an economic and operational standpoint, and would have solved this issue (though not the door, obviously).
The logs should be getting pushed to a meaningful amount of local storage, and radio chatter saved centrally (there's almost certainly amateurs stockpiling these recordings - large institutions are definitely capable).
As far as I know, there's telemetry from the whole plain, not only the voice recording, so there might have been something useful ¯\_(ツ)_/¯
Edit: but just after responding I found out that the rest of the data is intact, so I was wrong
Yeah, I might have been unclear, I knew that other telemetry was available and it was just the voice recordings that were wiped due to the time they operated after the incident.
Telemetry is going to be numerical data that likely compresses very well, so even with a large amount of sensors I can't imagine it taking that much.
And yeah, voice users significantly less than video, where modern cheap dash cams can record days on a small SD card. Methinks flight recorders can do better. At the least they should be viable for the max flight time of the aircraft.
It sure seems like the flight systems were aware of a catastrophic failure of some sort and this could be automated. I mean why does this need manual intervention. It’s not like that data storage for that info is huge, or at least it shouldn’t be.
Either they don't care or they specifically want this data to not be reliably available.
Keep in mind this is just the voice recordings (what was said inside the cabin and not transmitted), the avionics data and the transmissions they have.
Voice recorded data in this incident would get you what? The error was Boeing or door install. Voice recording catch errors of pilots.