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I'll be honest I don't know a lot about the brand new airplanes, but one think I do recall a lot of from reading accident reports is that they typically only recorded the last 30 minutes of data.

When an aircraft costs over 30 million USD, with some costing in excess or $300 million, surely being able to increase the amount of data recorded 10x or 20x pales in comparison to the costs?

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    $\begingroup$ Possible duplicate $\endgroup$ – TomMcW Aug 9 '17 at 18:58
  • $\begingroup$ Downvoted due to factual inaccuracies in the question: CVR's store each channel for 30 minutes, but the area mic (or, the sum of everything being said & heard) for 120 minutes. Modern FDR's store far, far more than 30 minutes of data. $\endgroup$ – Ralph J Aug 9 '17 at 20:22
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    $\begingroup$ @RalphJ A lot of questions here come from a misunderstanding of the facts. 30 minutes is a common misconception too so in my opinion it doesn't deserve a downvote. $\endgroup$ – Ben Aug 9 '17 at 21:03
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CVRs typically store two hours of voice recordings (source).

It simply wouldn't serve any purpose to store longer recordings.
It is extremely rare for an emergency to last for such an extended time.
Qantas 32 was one of the longest emergencies in recent memory, and it was only 1:45.

The MH370 flight was longer, of course, but it still hasn't been recovered.

While I'm sure it is technologically possible to record more voice data, that would primarily record innocuous and routine conversations among the pilots.

I suspect that the pilots, and their unions, are reluctant to have their mundane and irrelevant conversations recorded and inspected.

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    $\begingroup$ Good points, I was just thinking about the recent incident of the near-miss at SFO, supposedly the CVR wasn't turned off and the entire incident was wiped from the recorder, something that would have been avoided if it had the ability to record longer. Also I would imagine that data would be protected under existing data privacy laws and would only be accessible in the event of an incident, with regards to your point about pilot convesation privacy. $\endgroup$ – Ksery Aug 9 '17 at 19:24
  • $\begingroup$ "would only be accessible in the event of an incident" is very important, especially in the context of AC759. There was not actually a crash, and the plane landed safely. While everyone would love to know what the pilots were thinking/saying, CVRs cannot be pulled arbitrarily. The NTSB has rules about how pilot recordings can used / must not be used. $\endgroup$ – abelenky Aug 9 '17 at 19:27
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    $\begingroup$ I don't think anyone would be surprised if you called the event an 'incident'. The plane was only a few feet from landing on top of two fully fueled airliners waiting on the taxiway. And like I said, the data would remain protected, as I assume it is now, and can only be pulled when a serious incident occurs, like the near miss at SFO. Im sure the NTSB and other regulatory agencies have already set the benchmark for what classifies as an "incident" and whether to pull the recorders data. $\endgroup$ – Ksery Aug 9 '17 at 19:46

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