Originally Posted by
bubbers44
...... Did the A300 really have rudder inputs from the pedals like it showed in the video or did they just use rudder actuator inputs to the FDR to show what the rudder pedals would do to make the rudder move? ........... Does the Airbus really have rudder pedal movement in their FDR. Years ago I heard no.
There was an FAA mandate to install control input data sensors by August 2001. The CP data acquisition system was installed on this aircraft and was manufactured by a company in Florida.
This particular FDR records a digitised and filtered version of the control sensor data at a rate of only twice per second or 2hz. Data filtering is something the FAA/NTSB are moving to end as the practice can cause gaps in recorded data or miss extreme data points altogether and was apparent in this case.
A couple of points:
On examining the rudder pedal input data, the NTSB threw out American Airlines certificated correlation tables and proceeded to produce their own by a statistical averaging technique based on previous flight data. The newly created tables were then used to interpret the recorded rudder pedal data points.
Both in public hearings and the periodic updates, the NTSB chose only to reveal averaged amalgamations of the data with no reports available of the actual numbers recorded on the FDR.
In light of the data limitations and subsequent NTSB percolations, we should take the animations and graphs of flight control inputs with more than a few grains of salt.