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Attributes | |
ACN | 735529 |
Time | |
Date | 200704 |
Local Time Of Day | 1801 To 2400 |
Place | |
Locale Reference | airport : zzz.airport |
State Reference | US |
Altitude | agl single value : 0 |
Aircraft 1 | |
Controlling Facilities | tower : zzz.tower |
Operator | common carrier : air carrier |
Make Model Name | Regional Jet 700 ER&LR |
Operating Under FAR Part | Part 121 |
Person 1 | |
Affiliation | company : air carrier |
Function | maintenance : inspector |
ASRS Report | 735529 |
Person 2 | |
Affiliation | company : air carrier |
Function | maintenance : technician |
ASRS Report | 735526 |
Events | |
Anomaly | aircraft equipment problem : critical maintenance problem : improper maintenance non adherence : published procedure non adherence : far |
Independent Detector | aircraft equipment other aircraft equipment : elevators jamming other other : 1 |
Consequence | other other |
Factors | |
Maintenance | contributing factor : manuals contributing factor : briefing performance deficiency : non compliance with legal requirements performance deficiency : installation performance deficiency : inspection performance deficiency : testing |
Supplementary | |
Problem Areas | Aircraft Chart Or Publication Maintenance Human Performance |
Primary Problem | Maintenance Human Performance |
Situations | |
Publication | Maint Manual And Engineering Order |
Narrative:
During accomplishment of engineering order; rods were installed incorrectly. Technicians and inspector were tasked with accomplishing engineering order; service bulletin; replacement of elevator levers. Before starting work on aircraft; technicians performed an elevator movement check to verify full up and down travel on cockpit status screen indicator; and record degrees of movement. Indications were correct. Aircraft had panels removed with 1 technician on r-hand side of vertical stabilizer in scissor style manlift; and another on the l-hand side in bucket style manlift. Before elevator system work was started; rig pins P1; P2; P3; and P4 were installed to check for freedom of movement. Replacement of elevator levers was accomplished. After break; rigging procedure was started with 2 technicians in bucket style manlift on l-hand side of vertical. Hydraulic pressure was needed to center elevators and give correct freedom of movement at rig pin P1. After rigging adjustments; freedom of movement at rig pins P1; P2; P3; and P4 was good. The nut cotter pins; nut safeties and rod end witness holes checked good. 2 technicians went to cockpit and 1 was at the elevator area. Operations check was performed by doing 4 complete up and down cycles of elevators; by individual hydraulic system and by all system running together. Each cycle full up and down travel on status screen indicator was verified. Also at each cycle mdc degrees of movement was verified to be the same as before service bulletin started. Later the aircraft was at the gate and the flight crew reported that the elevator was jamming up. The flight was canceled and the aircraft was taken back to the hangar. Another mechanic found that we had installed the control rod backwards and was causing the jamming. Not sure how we got the rods mixed around; but the operations check went good and the elevator moved freely with no jamming. Operations check was good according to the inspector. 1 inspector person; the long procedure time and working from a manlift create an interruption distraction to technician and inspector. Working from a bucket style manlift which is small for 2 persons and tools. The bucket is constantly having to be moved left; right; up and down to access areas needed. Also moving from elevator area to floor for tools; parts and inspector. Aircraft was moved to hangar for troubleshooting. First shift technicians felt that column movement was ok. Second shift technicians felt movement at full aft was stiff. A third shift technician who had previously completed the same service bulletin and initially mispositioned the rods at new levers found the problem area.
Original NASA ASRS Text
Title: A CRJ-700 ACFT WAS FOUND TO HAVE ELEVATORS JAMMING UP DURING PREFLIGHT AFTER MAINT REPLACED ELEVATOR LEVERS.
Narrative: DURING ACCOMPLISHMENT OF ENGINEERING ORDER; RODS WERE INSTALLED INCORRECTLY. TECHNICIANS AND INSPECTOR WERE TASKED WITH ACCOMPLISHING ENGINEERING ORDER; SVC BULLETIN; REPLACEMENT OF ELEVATOR LEVERS. BEFORE STARTING WORK ON ACFT; TECHNICIANS PERFORMED AN ELEVATOR MOVEMENT CHK TO VERIFY FULL UP AND DOWN TRAVEL ON COCKPIT STATUS SCREEN INDICATOR; AND RECORD DEGREES OF MOVEMENT. INDICATIONS WERE CORRECT. ACFT HAD PANELS REMOVED WITH 1 TECHNICIAN ON R-HAND SIDE OF VERT STABILIZER IN SCISSOR STYLE MANLIFT; AND ANOTHER ON THE L-HAND SIDE IN BUCKET STYLE MANLIFT. BEFORE ELEVATOR SYS WORK WAS STARTED; RIG PINS P1; P2; P3; AND P4 WERE INSTALLED TO CHK FOR FREEDOM OF MOVEMENT. REPLACEMENT OF ELEVATOR LEVERS WAS ACCOMPLISHED. AFTER BREAK; RIGGING PROC WAS STARTED WITH 2 TECHNICIANS IN BUCKET STYLE MANLIFT ON L-HAND SIDE OF VERT. HYD PRESSURE WAS NEEDED TO CTR ELEVATORS AND GIVE CORRECT FREEDOM OF MOVEMENT AT RIG PIN P1. AFTER RIGGING ADJUSTMENTS; FREEDOM OF MOVEMENT AT RIG PINS P1; P2; P3; AND P4 WAS GOOD. THE NUT COTTER PINS; NUT SAFETIES AND ROD END WITNESS HOLES CHKED GOOD. 2 TECHNICIANS WENT TO COCKPIT AND 1 WAS AT THE ELEVATOR AREA. OPS CHK WAS PERFORMED BY DOING 4 COMPLETE UP AND DOWN CYCLES OF ELEVATORS; BY INDIVIDUAL HYD SYS AND BY ALL SYS RUNNING TOGETHER. EACH CYCLE FULL UP AND DOWN TRAVEL ON STATUS SCREEN INDICATOR WAS VERIFIED. ALSO AT EACH CYCLE MDC DEGREES OF MOVEMENT WAS VERIFIED TO BE THE SAME AS BEFORE SVC BULLETIN STARTED. LATER THE ACFT WAS AT THE GATE AND THE FLT CREW RPTED THAT THE ELEVATOR WAS JAMMING UP. THE FLT WAS CANCELED AND THE ACFT WAS TAKEN BACK TO THE HANGAR. ANOTHER MECH FOUND THAT WE HAD INSTALLED THE CTL ROD BACKWARDS AND WAS CAUSING THE JAMMING. NOT SURE HOW WE GOT THE RODS MIXED AROUND; BUT THE OPS CHK WENT GOOD AND THE ELEVATOR MOVED FREELY WITH NO JAMMING. OPS CHK WAS GOOD ACCORDING TO THE INSPECTOR. 1 INSPECTOR PERSON; THE LONG PROC TIME AND WORKING FROM A MANLIFT CREATE AN INTERRUPTION DISTR TO TECHNICIAN AND INSPECTOR. WORKING FROM A BUCKET STYLE MANLIFT WHICH IS SMALL FOR 2 PERSONS AND TOOLS. THE BUCKET IS CONSTANTLY HAVING TO BE MOVED L; R; UP AND DOWN TO ACCESS AREAS NEEDED. ALSO MOVING FROM ELEVATOR AREA TO FLOOR FOR TOOLS; PARTS AND INSPECTOR. ACFT WAS MOVED TO HANGAR FOR TROUBLESHOOTING. FIRST SHIFT TECHNICIANS FELT THAT COLUMN MOVEMENT WAS OK. SECOND SHIFT TECHNICIANS FELT MOVEMENT AT FULL AFT WAS STIFF. A THIRD SHIFT TECHNICIAN WHO HAD PREVIOUSLY COMPLETED THE SAME SVC BULLETIN AND INITIALLY MISPOSITIONED THE RODS AT NEW LEVERS FOUND THE PROB AREA.
Data retrieved from NASA's ASRS site as of January 2009 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.