Cessna Aircraft Company 404, VH-WGB

A Cessna 404 Titan aircraft was engaged in low level geophysical
survey work near Tennant Creek, NT. The pilot reported that as he
was manoeuvring the aircraft at the completion of a survey run, he
became aware that the aircraft's response to aileron control input
was reduced. He was able to roll the aircraft to wings level
attitude using a combination of aileron and rudder, before climbing
the aircraft to approximately 6,000 ft and returning to Tennant
Creek aerodrome.

Examination of the aileron control system by company maintenance
personnel revealed that one of the aileron cables had separated
near a change of direction pulley below the control pedestal in the
cockpit. Company maintenance personnel reported that there were no
obvious signs of fatigue or wear at the failure point and that the
reason for the failure was not immediately apparent. The cable
could not be identified by manufacturer or part number.

The aircraft had undergone a routine scheduled maintenance
inspection 29 hours prior to the event. The engineer reported that
it was difficult to inspect the cable in the area beneath the
control pedestal during normal scheduled inspections. It was
suggested that the only way to adequately examine it would be to
disconnect and remove it in accordance with the manufacturers major
maintenance requirements.

The aircraft logbooks showed that the aircraft was manufactured
in 1981, and had been imported into Australia from Indonesia. At
the time of the occurrence it had a total time in service of 3,853
hours. The aircraft log books did not indicate any previous
replacement of the aileron cable.

The maintenance engineer advised that, following the incident,
he submitted the cable and a detailed major defect report to the
local CASA office. CASA Airworthiness advised that their
examination was not able to identify the reason for the failure
with any certainty. They confirmed that there were no serial or
part numbers on the cable and that it was probably not the correct
specification for this type of installation. The most likely
senario was that the cable was manufactured and fitted to the
aircraft in Indonesia.