FAA AC_20-141B_Chg1 Airworthiness and Operational Approval of Digital Flight Data Recorder Systems

This advisory circular (AC) provides information on certification (design and installation) and continued airworthiness of digital flight data recorder systems (DFDRS). DFDRS provide information for an investigative authority���the National Transportation Safety Board (NTSB) in the United States���to conduct more thorough investigations of accidents and incidents. The data recorded is also used by operators to enable the prediction of trends that may be useful in determining modifications needed to avoid accidents and incidents.