Maintenance Repairman
Communication Breakdown; Situational Awareness
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Other / Unknown
General Maintenance Action
Human Factors; MEL; Procedure; Chart Or Publication; Aircraft; Manuals
Mechanic Y reinstalled a First Officer's Pitch Trim switch on a EMB-145 aircraft; which I inspected and back-signed.  I did not notice it was installed 180-degrees from the proper position.  We then made a Logcan discrepancy [write-up] for an Operational Check for the replacement of the switch.  At the time we could not apply power to the aircraft to perform the Operational Check; so it was turned over to the night shift.   When the Operational Check was complied with; it was not caught that the Horizontal Stabilizer was moving in the wrong direction.  I have completed and submitted an inspection manual discrepancy report. Due to the severity of this incident; the manual in question needs to have a warning and possibly an illustration of the proper orientation of the Pitch Trim switch.
Mechanic reports he inspected; but did not notice a Horizontal Stabilizer (H/S) Pitch Trim switch had been installed 180-degrees from the proper position on an EMB-145 aircraft. An Operational Check of the Pitch Trim by another shift failed to notice the H/S moving in the opposite direction contributing to an inflight incident.