Narrative:

Air carrier flight was en route to ZZZ and had a maintenance discrepancy. The discrepancy was that on takeoff from zza, the crew observed right rudder out of trim. The crew centered the rudder on the triangle on the pfd and then used rudder trim to keep triangle centered on rudder indicator. It took 1.5 units left of center. Also aileron trim was .5 units down left. Autoplt on held above trim settings. Contract maintenance cleared the in-flight discrepancy with the following maintenance action: upon visual inspection of yaw damper, found #1 yaw damper disconnected, reconnected yaw damper. In accordance with canadair regional jet aircraft maintenance manual chapter 22-22-01 performed operations check good. The mechanic in ZZZ wrote a statement that, 'the #1 yaw damper actuator was not connected at the bottom eyelet of the actuator, and that the bolt was through the bracket and correctly cotter pinned at the nut.' prior to the flight to ZZZ, aircraft xyz ferried into zza from zzb for ferry flight maintenance. The ferry flight discrepancy was 'Y/D #1 status message and unable to reengage.' I was one of the avionics technicians that performed the maintenance diagnostic tests on both the #1 and #2 yaw damper actuators. It was discovered that the #1 yaw damper would not pass the checks per the crj manual and would disconnect. The aircraft was at a remote location on the airport ramp. It was late in the evening, somewhere around xa:00 when I began performing the task of replacing the #1 yaw damper actuator. A de-ice truck bucket had to be used to access the yaw damper actuators, which are located up in the horizontal stabilizer. The crj procedure for replacing the #1 yaw damper actuator basically calls for removing two panels on the right side of the stabilizer, installing a rig pin, removing the #2 yaw damper actuator, and reaching into the access and removing the #1 yaw damper actuator. As I began to reinstall the serviceable #1 yaw damper actuator, the sun set. I was up near the tail of the aircraft in the bucket, using artificial light to see. I seemed to have some difficulty getting the bolt through the a/C bracket and the eyelet of the #1 yaw damper actuator. After some time, the eyelet and bracket lined up and the bolt slipped into position. With the flashlight, I looked into the access hole, moving my line of sight around, visually confirming that the bracket and eyelet aligned properly. I then applied the nut onto the bolt, tightened the two and applied the cotter pin, all with great difficulty due to no access panel on the left side of the stabilizer. The #2 yaw damper actuator was installed, bolted, and pinned. The rig pin was removed and both of the yaw damper actuators passed the crj procedures for operational check. The inspector confirmed that the operation and installation of both actuators was performed satisfactorily per the crj procedures. The panels were then installed and the aircraft was signed off and released for flight. Callback conversation with reporter revealed the following information: the reporter stated the actuator was installed using maintenance manual 22-22-01. Access to the #1 and #2 yaw damper actuators is through two panels on the right side of the vertical stabilizer so #2 actuator must be removed to see and remove the #1 actuator. The #1 actuator was very difficult to remove and install because of reaching across the width of the vertical stabilizer while working from a deicing bucket that was free to swing. The most difficult problem was aligning the lower actuator rod end and inserting the bolt, washer, nut and cotter pin due to limited visibility. The actuator was inspected and the panels secured. No visual inspection was made of the actuator operation before close up nor was it required to be per the maintenance manual. The #1 and #2 actuators were checked per the operational check MM 22-22-01 including visual observation of rudder movement. The reporter stated this job should be performed in a hangar with adequate lighting and from a tail stand.

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Original NASA ASRS Text

Title: A CANADAIR CL-65 WAS DISPATCHED IN NON COMPLIANCE WITH THE #1 YAW DAMPER ACTUATOR ROD END NOT CONNECTED TO THE LEVER ASSEMBLY.

Narrative: ACR FLT WAS EN ROUTE TO ZZZ AND HAD A MAINT DISCREPANCY. THE DISCREPANCY WAS THAT ON TKOF FROM ZZA, THE CREW OBSERVED RIGHT RUDDER OUT OF TRIM. THE CREW CENTERED THE RUDDER ON THE TRIANGLE ON THE PFD AND THEN USED RUDDER TRIM TO KEEP TRIANGLE CENTERED ON RUDDER INDICATOR. IT TOOK 1.5 UNITS LEFT OF CENTER. ALSO AILERON TRIM WAS .5 UNITS DOWN LEFT. AUTOPLT ON HELD ABOVE TRIM SETTINGS. CONTRACT MAINT CLRED THE IN-FLT DISCREPANCY WITH THE FOLLOWING MAINT ACTION: UPON VISUAL INSPECTION OF YAW DAMPER, FOUND #1 YAW DAMPER DISCONNECTED, RECONNECTED YAW DAMPER. IN ACCORDANCE WITH CANADAIR REGIONAL JET ACFT MAINT MANUAL CHAPTER 22-22-01 PERFORMED OPS CHK GOOD. THE MECHANIC IN ZZZ WROTE A STATEMENT THAT, 'THE #1 YAW DAMPER ACTUATOR WAS NOT CONNECTED AT THE BOTTOM EYELET OF THE ACTUATOR, AND THAT THE BOLT WAS THROUGH THE BRACKET AND CORRECTLY COTTER PINNED AT THE NUT.' PRIOR TO THE FLT TO ZZZ, ACFT XYZ FERRIED INTO ZZA FROM ZZB FOR FERRY FLT MAINT. THE FERRY FLT DISCREPANCY WAS 'Y/D #1 STATUS MESSAGE AND UNABLE TO REENGAGE.' I WAS ONE OF THE AVIONICS TECHNICIANS THAT PERFORMED THE MAINT DIAGNOSTIC TESTS ON BOTH THE #1 AND #2 YAW DAMPER ACTUATORS. IT WAS DISCOVERED THAT THE #1 YAW DAMPER WOULD NOT PASS THE CHKS PER THE CRJ MANUAL AND WOULD DISCONNECT. THE ACFT WAS AT A REMOTE LOCATION ON THE ARPT RAMP. IT WAS LATE IN THE EVENING, SOMEWHERE AROUND XA:00 WHEN I BEGAN PERFORMING THE TASK OF REPLACING THE #1 YAW DAMPER ACTUATOR. A DE-ICE TRUCK BUCKET HAD TO BE USED TO ACCESS THE YAW DAMPER ACTUATORS, WHICH ARE LOCATED UP IN THE HORIZONTAL STABILIZER. THE CRJ PROC FOR REPLACING THE #1 YAW DAMPER ACTUATOR BASICALLY CALLS FOR REMOVING TWO PANELS ON THE RIGHT SIDE OF THE STABILIZER, INSTALLING A RIG PIN, REMOVING THE #2 YAW DAMPER ACTUATOR, AND REACHING INTO THE ACCESS AND REMOVING THE #1 YAW DAMPER ACTUATOR. AS I BEGAN TO REINSTALL THE SERVICEABLE #1 YAW DAMPER ACTUATOR, THE SUN SET. I WAS UP NEAR THE TAIL OF THE ACFT IN THE BUCKET, USING ARTIFICIAL LIGHT TO SEE. I SEEMED TO HAVE SOME DIFFICULTY GETTING THE BOLT THROUGH THE A/C BRACKET AND THE EYELET OF THE #1 YAW DAMPER ACTUATOR. AFTER SOME TIME, THE EYELET AND BRACKET LINED UP AND THE BOLT SLIPPED INTO POS. WITH THE FLASHLIGHT, I LOOKED INTO THE ACCESS HOLE, MOVING MY LINE OF SIGHT AROUND, VISUALLY CONFIRMING THAT THE BRACKET AND EYELET ALIGNED PROPERLY. I THEN APPLIED THE NUT ONTO THE BOLT, TIGHTENED THE TWO AND APPLIED THE COTTER PIN, ALL WITH GREAT DIFFICULTY DUE TO NO ACCESS PANEL ON THE LEFT SIDE OF THE STABILIZER. THE #2 YAW DAMPER ACTUATOR WAS INSTALLED, BOLTED, AND PINNED. THE RIG PIN WAS REMOVED AND BOTH OF THE YAW DAMPER ACTUATORS PASSED THE CRJ PROCS FOR OPERATIONAL CHK. THE INSPECTOR CONFIRMED THAT THE OPERATION AND INSTALLATION OF BOTH ACTUATORS WAS PERFORMED SATISFACTORILY PER THE CRJ PROCS. THE PANELS WERE THEN INSTALLED AND THE ACFT WAS SIGNED OFF AND RELEASED FOR FLT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACTUATOR WAS INSTALLED USING MAINT MANUAL 22-22-01. ACCESS TO THE #1 AND #2 YAW DAMPER ACTUATORS IS THROUGH TWO PANELS ON THE RIGHT SIDE OF THE VERTICAL STABILIZER SO #2 ACTUATOR MUST BE REMOVED TO SEE AND REMOVE THE #1 ACTUATOR. THE #1 ACTUATOR WAS VERY DIFFICULT TO REMOVE AND INSTALL BECAUSE OF REACHING ACROSS THE WIDTH OF THE VERTICAL STABILIZER WHILE WORKING FROM A DEICING BUCKET THAT WAS FREE TO SWING. THE MOST DIFFICULT PROB WAS ALIGNING THE LOWER ACTUATOR ROD END AND INSERTING THE BOLT, WASHER, NUT AND COTTER PIN DUE TO LIMITED VISIBILITY. THE ACTUATOR WAS INSPECTED AND THE PANELS SECURED. NO VISUAL INSPECTION WAS MADE OF THE ACTUATOR OPERATION BEFORE CLOSE UP NOR WAS IT REQUIRED TO BE PER THE MAINT MANUAL. THE #1 AND #2 ACTUATORS WERE CHECKED PER THE OPERATIONAL CHECK MM 22-22-01 INCLUDING VISUAL OBSERVATION OF RUDDER MOVEMENT. THE RPTR STATED THIS JOB SHOULD BE PERFORMED IN A HANGAR WITH ADEQUATE LIGHTING AND FROM A TAIL STAND.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.