It automatically overwrites periodically.
Correct, it runs on a 2 hour loop. If not turned off, it keeps running.
Interesting in Europe they run on 25 hour loops. Wonder why?
Because the Airline companies and Pilots did not want it running move than 2 hours so that there would be no record of “embarrassing” recording. In the age of digital recordings and hardware, seems to me 2 hours dates back to a time of TEAC recorders! Equally ironic, when we used body in my job in the 70s, we had recorders that ran for almost 4 hours, AIDS.
Which is why, if it looks like a review will be required, the crew can pull a circuit breaker to cut power, stop the overwriting, and preserve the record...?
There is 2 hours of storage on the unit. it records over everything more than 1 hour, 59 minutes and 59 seconds old. The only way to stop if recording is to disable it. That means pulling the breaker.
We don’t save 25 hours of recordings because the pilot’s UNION objects. Plain and simple.