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1.14.3.2.2 During recording, the old data was erased immediately prior to the recording of new data. The erase feature was incorporated on the Sundstrand DFDR because of the magnetic characteristics of the metal tape.
1.14.3.2.3 As with the CVR, the tape transport was installed in an armoured and heat insulated container mounted on a chassis that was slid into a light outer box. Power supplies and associated electronics were mounted on the chassis ahead of and behind the container. Again, only the tape in its container was expected to survive a major accident.
1.14.3.2.4 The FDAU was installed in the Main Equipment Centre immediately ahead of the forward cargo compartment. The DFDR was installed in the Aft Equipment Centre adjacent to the CVR. Cables carrying both the serial digital signal and the power supply to the DFDR were fed along the fuselage on the left side above the main passenger cabin in the same raceway as the signal inputs to the CVR.
1.14.3.3
1.14.3.3.1
1.14.3.3.2
DFDR parameter list
The DFDR recorded the following parameters:
Acceleration (lateral, longitudinal and vertical), altitude (coarse and fine), calibrated airspeed, control column position in pitch, control wheel position in roll, engine pressure ratio for engines No. 2 and 3, flap configuration, VHF and HF keying for HF 1 and 2 and VHF 1, 2 and 3; magnetic heading, pitch and roll attitude; rudder pedal position, horizontal stabilizer position, thrust reverser state for each engine, radio altimeter; autopilot (in and out of Manual, and in and out of Command), and marker beacon (outer and middle).
A parameter list provided by representatives of the Republic of Korea contained also the following parameters: UTC, VOR/ILS localizer and glide slope, engine pressure ratio for engines No. 1 and 4, and GPWS. However, these parameters showed no activation throughout the duration of the recordings.
1.14.3.3.3 As UTC was not recorded, reliance had to be placed on elapsed time based on the data clocking rate. Although this rate was based on a crystal oscillator and was therefore inherently accurate, difficulties were encountered when there were losses of data synchronization.
1.14.3.4
1.14.3.4.1
Inspection of the DFDR components
Examination of the tape transport confirmed that it was from a Sundstrand 573A DFDR. A handwritten "S/N 3069" on the plate that covered the tape reels and also on one of the posts supporting this plate, was the same as the serial number of the DFDR installed on KE 007.
1.14.3.4.2
The armoured container had a crack, approximately 1.5 inches in length, emanating from the lower corner of the top cover nearest to the front face of the recorder. The four screws which attached the cover to the container had suffered excessive shear loads along the plane of the joint between the two parts. The lack of evidence of any concentrated mechanical loads being applied to the exterior of the container indicated that the damage might have resulted from a high speed water impact.