Flight control system event, Boeing 737-700, VH-VBD

At 2108 Eastern Standard Time on 09 August 2005, a Boeing Company 737-700 aircraft, registered VH-VBD, completed a scheduled flight from Melbourne, Victoria to Sydney, NSW. The pilot then reported that the aircraft had 'heavy' flight controls. An inspection by maintenance engineers revealed that the left lower rear elevator cable was incorrectly routed around a stiffener and that the stiffener and cable section had been damaged as a result of contact between them. The aircraft was withdrawn from service for repairs.

In the last week of July 2005, a contract maintenance organisation had replaced eight elevator control cable sections during a scheduled heavy aircraft maintenance check. The cables were replaced to comply with Boeing Company service bulletin 737-27-1254 revision 1.

While preparing the rear elevator control cables for removal, a cable end was not secured at the lower left rear elevator input quadrant, before removing the cable keeper. When the cable keeper was removed, the unsecured cable section slipped from sight. While recovering the cable, it was inadvertently misrouted around a fuselage stiffener. When the new cable was pulled into place it followed the same incorrect route around the stiffener.  This resulted in contact between the cable and the stiffener.

As a result of the occurrence, the contract maintenance organisation implemented a number of changes to improve maintenance planning and documentation.