B737-700
Maintenance Powerplant; Maintenance Airframe
Maintenance Inspector 7; Maintenance Technician 22
Workload; Situational Awareness; Fatigue; Distraction
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Incorrect / Not Installed / Unavailable Part; Human Factors; Chart Or Publication
I was involved in a Horizontal Stabilizer jackscrew Remove and Replace (R/R). [The B737-700] was a late arrival. The R/R of the maintenance task was accomplished and the job was complete at approximately (time). When my portion of the checkout of the area of concern was accomplished; I remember physically grabbing the rod and shaking it to make sure it was secure. It is possible that the rod had been jammed giving it the appearance that it was secured correctly. It was discovered on a Heavy C Check that the rod was not secured properly. Aircraft arrived late; and had an early departure. I felt the pressures to get this Aircraft back in service in a timely manner. I believe fatigue played a factor in this event as I work the graveyard shift. In addition to physically grabbing the rod and shaking it; I should have paid more attention to detail. I was new to the Inspection department at that time. This event happened approximately 9 months ago and can't remember all the specific details.
Reporter stated that part of the B737-700 Job Card to Remove and Replace (R/R) the Horizontal Stabilizer is to disconnect the Stabilization rod (Secondary rod) and loosen up the Forward Cable Drum under the cockpit floor in order to remove the Horizontal Stabilizer Jackscrew Assembly in the tail compartment. The Stabilization rod attaches to the forward side of the Forward Cable Drum and is reattached after the Horizontal Stabilizer Jackscrew is installed and the Horizontal Stabilizer Manual Trim cable tensions are accomplished. There is only one rod on 'Classic' B737s.Reporter stated one of the issues with the Job Card is the five parts or steps with only one sign-off on the Job Card for the Forward Cable Drum installation. The bolt that attaches the Stabilization rod; lower rod end; to a clevis fitting on the forward side of the Forward Cable Drum was found installed but not secured. The B737-700 had been flying around for ten months until a Maintenance C-Check crew noticed the unsecured bolt.
An Aircraft Maintenance Inspector was informed that an attached bolt for a Stabilization rod to the Forward Cable Drum Assembly on a B737-700 aircraft was found not properly secured after he had performed an inspection of the Cable Drum re-installation.