That's surprising that the black box overwrites itself after 2 hours of recording. This article linked to an article I missed about how the plane that had the door/panel fall off had the cockpit audio overwritten because it wasn't collected in time.
The black box isn't like a modern hard drive, with terabytes of storage. They're often old, and even the modern ones need to put so much effort into protection against things like fire, seawater and collisions that they don't have as much space as you might imagine.
They have to rely on someone going out of their way to take the box out, or shut down the plane, because the alternative would be for them to have some way to decide for themselves to stop recording. If they could do that then a false positive would cause them to miss potentially important data, so they're designed to keep going until someone makes it stop
That sounds like something they need to improve on then. Two hours is a ridiculously short amount of time given the tech we have in 2024.
In industry, minimum means that's what you're getting
It's like seeing something labeled military grade.
Regulations. Everything requires so much time/effort to certify and cost. Even as technology has moved forward, they have to recoup their investment in certifying the equipment.
I guarantee that if the regulations didn't state a minimum of 2 hours or the need for black boxes, aircraft manufacturer would put a 1 minute tape recorder inside a foam box. If they even put in anything.
So the old tech is somehow better and smaller than a modern SSD?
Doubt
I didn't say anything like that. The black box is physically much bigger than a modern SSD, but stores far less data because of all the extra problems it has to deal with
So what problems would a modern SSD not be better at?
Being hit by a truck, then catching fire and being allowed to burn while doused in jet fuel for a while before being dunked in seawater for a few days.
I'll bet you can't find an SSD which can do that.
Which is why it's in the protective box?
The flight recorder itself doesn't do that either. Just the case surrounding it. You could just as well put an SSD in it. Hell it would probably be better as older tech was more vulnerable to vibrations.
Of-the-shelf SSDs are optimized for speed and price.
Flight recorders are typically specified to withstand an impact of 3400 g and temperatures of over 1,000 °C (1,830 °F), exposure to salt water, and high pressure if it sinks to the bottom of the sea as required by EUROCAE ED-112.
Maybe you could design a flight recorder that uses SSDs, but then you must get it certified again for the new hardware, which will cost a lot of money nobody wants to spend.
The next step in flight recorders is to also send a live feed of telemetric data back to some ground station so the last position of the plane is known - with a flight recorder you only get this data after you found the wreck. Currently submitting this signal is optional and can be turned of by the pilot, which is the reason why Malaysia Airlines Flight 370 is still missing.
Maybe you could design a flight recorder that uses SSDs,
Maybe? Really?
which will cost a lot of money nobody wants to spend.
I think this is probably more of the answer. Capitalism 101.
Black box were Solid State Drive before SSD were common, the advantages of no moving parts are simply too high.
Then it should be easy to add in a larger capacity modern drive?
This is why we can't have nice things.
"I don't understand the problem, therefore it must be simple and anyone not saying it's simple is obviously wrong"
Is it really a matter of how easy it is or how much it would cost to change it? I'm also talking about making a nicer/better version so I really don't understand your can't have nice things statement.
Yes, in the EU the minimum recording time was recently increased to 25h.
It is not a tech limitation anymore.
What is actually limiting are privacy concerns from misuse of the longer recording.
What kind of privacy data would be on a black box recorder? Just banter between flight crew? They are in a work environment so the recorded conversations should be kept professional anyway, IMO.
There's a proposal by the FAA (here) to increase the length to 25h for new planes.
There have been catastrophic events that took longer than 2h by themselves to manifest, so they lost the beginning of the disaster by this stupidly short record duration.
That's surprising that the black box overwrites itself after 2 hours of recording. This article linked to an article I missed about how the plane that had the door/panel fall off had the cockpit audio overwritten because it wasn't collected in time.
The black box isn't like a modern hard drive, with terabytes of storage. They're often old, and even the modern ones need to put so much effort into protection against things like fire, seawater and collisions that they don't have as much space as you might imagine.
They have to rely on someone going out of their way to take the box out, or shut down the plane, because the alternative would be for them to have some way to decide for themselves to stop recording. If they could do that then a false positive would cause them to miss potentially important data, so they're designed to keep going until someone makes it stop
That sounds like something they need to improve on then. Two hours is a ridiculously short amount of time given the tech we have in 2024.
It's not like we don't have the technology
As of 2008 it is an FAA requirement that the recording duration is a minimum of two hours.
Just designed to (minimum) spec.
In industry, minimum means that's what you're getting
It's like seeing something labeled military grade.
Regulations. Everything requires so much time/effort to certify and cost. Even as technology has moved forward, they have to recoup their investment in certifying the equipment.
I guarantee that if the regulations didn't state a minimum of 2 hours or the need for black boxes, aircraft manufacturer would put a 1 minute tape recorder inside a foam box. If they even put in anything.
So the old tech is somehow better and smaller than a modern SSD?
Doubt
I didn't say anything like that. The black box is physically much bigger than a modern SSD, but stores far less data because of all the extra problems it has to deal with
So what problems would a modern SSD not be better at?
Being hit by a truck, then catching fire and being allowed to burn while doused in jet fuel for a while before being dunked in seawater for a few days.
I'll bet you can't find an SSD which can do that.
Which is why it's in the protective box?
The flight recorder itself doesn't do that either. Just the case surrounding it. You could just as well put an SSD in it. Hell it would probably be better as older tech was more vulnerable to vibrations.
Of-the-shelf SSDs are optimized for speed and price.
Flight recorders are typically specified to withstand an impact of 3400 g and temperatures of over 1,000 °C (1,830 °F), exposure to salt water, and high pressure if it sinks to the bottom of the sea as required by EUROCAE ED-112.
Maybe you could design a flight recorder that uses SSDs, but then you must get it certified again for the new hardware, which will cost a lot of money nobody wants to spend. The next step in flight recorders is to also send a live feed of telemetric data back to some ground station so the last position of the plane is known - with a flight recorder you only get this data after you found the wreck. Currently submitting this signal is optional and can be turned of by the pilot, which is the reason why Malaysia Airlines Flight 370 is still missing.
Maybe? Really?
I think this is probably more of the answer. Capitalism 101.
Black box were Solid State Drive before SSD were common, the advantages of no moving parts are simply too high.
Then it should be easy to add in a larger capacity modern drive?
This is why we can't have nice things.
"I don't understand the problem, therefore it must be simple and anyone not saying it's simple is obviously wrong"
Is it really a matter of how easy it is or how much it would cost to change it? I'm also talking about making a nicer/better version so I really don't understand your can't have nice things statement.
Yes, in the EU the minimum recording time was recently increased to 25h. It is not a tech limitation anymore. What is actually limiting are privacy concerns from misuse of the longer recording.
What kind of privacy data would be on a black box recorder? Just banter between flight crew? They are in a work environment so the recorded conversations should be kept professional anyway, IMO.
There's a proposal by the FAA (here) to increase the length to 25h for new planes.
There have been catastrophic events that took longer than 2h by themselves to manifest, so they lost the beginning of the disaster by this stupidly short record duration.