Boeing Gets FDR Comment Period Extended
Responding to a request by Boeing, the FAA has extended the comment deadline from today to April 16 on its proposal amending digital flight data recorder (DFDR) regulations of Parts 121 and 135 to prohibit “filtering” of signals. During several accident investigations, the NTSB found that some DFDRs were filtering signals before they were recorded. “As a result, the data being recorded did not accurately reflect the aircraft’s performance or the movements of the flight control systems,” the agency said. According to the FAA, during the design of DFDR systems, it appears that “convenience and a desire to reduce cost and complexity by eliminating multiple data paths have led to the DFDR recording filtered data rather than raw data.” The FAA projects that the defiltering modification would cost about $16,025 per airplane, although not all manufacturers agree. In its request for an extension to the comment period, Boeing said it needed more time to address several issues, including cost data.