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A flight data recorder (FDR) data frame is the order of the words that are transmitted from the digital flight data acquisition unit (DFDAU) to the digital FDR (DFDR) each second over many seconds (see ARINC 717 for additional information). Most FDR system data frames are made up of four subframes within one superframe. For a 64-words-per-second (wps) FDR system, a DFDAU will output 64 12-bit words to the FDR each second, where each word typically contains the value of an analog parameter. The order of the words (for example, word number 12 of the 64 words) within a subframe, as well as the order of the subframes, define an FDR data frame. This order is important to understand in order to decode the data recorded in the DFDR.

Some Boeing airplanes have two data frames, because one data frame in an FDR system with a capability of 64 wps cannot accommodate all of the world's regulatory requirements. By comparison, the 777 FDR system can handle 128 wps. In order to meet the new rule from the U.S. Federal Aviation Administration (FAA) that requires recording of 88 parameter groups by August 18, 2002, FDR systems on Boeing airplanes will handle 256 wps.