A B737-300 may have been returned to service with the stabilizer trim cables tensioned with the inco...

Attributes
ACN	645518
Time
Date	200501
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
Qualification	technician : powerplant technician : airframe
ASRS Report	645518
Person 2
Affiliation	company : air carrier
Function	maintenance : technician
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper maintenance maintenance problem : improper documentation non adherence : published procedure non adherence : far
Independent Detector	other other : 1
Resolutory Action	none taken : detected after the fact
Consequence	other other
Factors
Maintenance	performance deficiency : non compliance with legal requirements performance deficiency : scheduled maintenance performance deficiency : inspection
Supplementary
Problem Areas	Chart Or Publication Maintenance Human Performance Aircraft
Primary Problem	Maintenance Human Performance

Narrative:

I was working on one of the days between jan/sat/05 and jan/sun/05 and was working on a non routine. The non routine stated that 2 each cable pulleys for the stabilizer trim cable were changed and that the tension had been broke. I was to re-tension the cables. I pulled up the maintenance manual and checked what the tension should be (at 70 degrees it should be 130 pounds and use a #1 riser). I tensioned the cable; safetied and signed it off. On jan/sat/05; I was working an evening shift. There was a mechanic doing the same job I had done. I went up to him and said 'be sure to tension the cable at 70 degrees; 130 pound and #2C riser;' which is what I remember doing. He said 'no; it is a #1 riser.' that is when I started to think. I knew it was supposed to be a #1 riser; but I remember using a #2C. Once I recalled this; I filed a report. I notified ASRS report representative within 1 hour of discovering my mistake. I called maintenance control and talked with team lead and discussed having the cable tension rechked. He told me it would be a routine overnight check and he would have the tension checked then.

Original NASA ASRS Text

Title: A B737-300 MAY HAVE BEEN RETURNED TO SVC WITH THE STABILIZER TRIM CABLES TENSIONED WITH THE INCORRECT TOOL SETTING.

Narrative: I WAS WORKING ON ONE OF THE DAYS BTWN JAN/SAT/05 AND JAN/SUN/05 AND WAS WORKING ON A NON ROUTINE. THE NON ROUTINE STATED THAT 2 EACH CABLE PULLEYS FOR THE STABILIZER TRIM CABLE WERE CHANGED AND THAT THE TENSION HAD BEEN BROKE. I WAS TO RE-TENSION THE CABLES. I PULLED UP THE MAINT MANUAL AND CHKED WHAT THE TENSION SHOULD BE (AT 70 DEGS IT SHOULD BE 130 LBS AND USE A #1 RISER). I TENSIONED THE CABLE; SAFETIED AND SIGNED IT OFF. ON JAN/SAT/05; I WAS WORKING AN EVENING SHIFT. THERE WAS A MECH DOING THE SAME JOB I HAD DONE. I WENT UP TO HIM AND SAID 'BE SURE TO TENSION THE CABLE AT 70 DEGS; 130 LB AND #2C RISER;' WHICH IS WHAT I REMEMBER DOING. HE SAID 'NO; IT IS A #1 RISER.' THAT IS WHEN I STARTED TO THINK. I KNEW IT WAS SUPPOSED TO BE A #1 RISER; BUT I REMEMBER USING A #2C. ONCE I RECALLED THIS; I FILED A RPT. I NOTIFIED ASRS RPT REPRESENTATIVE WITHIN 1 HR OF DISCOVERING MY MISTAKE. I CALLED MAINT CTL AND TALKED WITH TEAM LEAD AND DISCUSSED HAVING THE CABLE TENSION RECHKED. HE TOLD ME IT WOULD BE A ROUTINE OVERNIGHT CHK AND HE WOULD HAVE THE TENSION CHKED THEN.

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.

A B737-300 may have been returned to service with the stabilizer trim cables tensioned with the incorrect tool setting.