RE:Real-Time Flight Data Streaming's Unfulfilled Potential"Beijing: The second black box of the crashed Chinese passenger plane has yet to be found, official media reported on Friday, retracting an earlier announcement that it has been recovered from the crash site."
"The second black box located in the back of the plane was stated to be the flight data recorder (FDR). The flight data recorder stores information about speed, altitude and direction, as well as pilot actions and performance of important systems."
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https://www.eastmojo.com/neighbourhood-watch/china/2022/03/25/second-black-box-of-crashed-chinese-plane-not-found-yet-official-media/ "Wuzhou: Recovery crews on Friday expanded the search area of the China Eastern Airlines crash, as the second of the plane’s two black boxes eluded search-and-rescue workers for a fourth day."
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https://mmnews.tv/china-expands-crash-search-to-find-second-black-box/ Sean Broderick
article: "Had China Eastern Airlines Flight 5735 been set up to offload FDR data at the first sign of trouble, stakeholders likely would have already known enough to take appropriate actions. Instead, nearly three days and counting after the tragedy, the reason why the Boeing 737-800 went from seemingly routine cruise to the side of a mountain within three minutes remains a mystery."