In aviation, a flight-data acquisition unit (FDAU) is a unit that receives various discrete, analog and digital parameters from a number of sensors and avionic systems and then routes them to a flight data recorder (FDR) and, if installed, to a Quick Access Recorder (QAR). Information from the FDAU to the FDR is sent via specific data frames, which depend on the aircraft manufacturer.
There is some trend towards integration of FDAU functions into software contained aboard other aircraft system components, as in the case of enhanced airborne flight recorders (EAFRs).