Narrative:

I was assigned to install a previously removed equipment rack #1. The equipment rack #1 and its associated electronic equipment on the rack #1 and #2 was not documented as being removed from the aircraft when I started the job. I found out about the missing document after the completion of the job. I also did not document the removal of the previously mentioned items. The equipment rack #1 was removed to replace a bad yaw damper coupler rack connector. This also was not documented as being changed before I started the job. I installed the equipment rack #1 and the electronic equipment for rack #1 and #2. I signed the work done as replaced the yaw damper coupler connector and an operational check accomplished ok. I did not document the installation and operational check of the equipment rack #1 and the electronic equipment on racks #1 and #2. There were 2 electronic components (cabin temperature controller and pressure controller) on the rack #1 that should have had an operational check by the electronic technician. Due to miscom this was not done. Only a low level pitot and static test was performed by me. A radio technician was required for operational check of the electronic equipment on the #1 and #2 rack. Due to the communication problem from the radio technician to the electronic technician the cabin temperature controller and the pressure controller operational check was not performed, resulting in an aircraft return to the station for a malfunction of the pressurization system. The static hose was not connected properly and became disconnected. According to our company maintenance manual and company standard practice manuals an inspector was required to check the work and this was not performed. The supervisors also did not question the lack of an inspection check. Any of which would have found the misinstalled pitot hose to the pressure controller, improper documentation of the electronic equipment rack and its electronic equipment.

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Original NASA ASRS Text

Title: A B737-200 AIRPLANE WAS IMPROPERLY REPAIRED RESULTING IN A RETURN TO THE FIELD ON ACCOUNT OF A PRESSURIZATION SYS FAILURE. FAILURE WAS CAUSED BY A PITOT STATIC HOSE NOT CONNECTED. APPROVED MAINT MANUAL DOCUMENTATION WAS NOT USED.

Narrative: I WAS ASSIGNED TO INSTALL A PREVIOUSLY REMOVED EQUIP RACK #1. THE EQUIP RACK #1 AND ITS ASSOCIATED ELECTRONIC EQUIP ON THE RACK #1 AND #2 WAS NOT DOCUMENTED AS BEING REMOVED FROM THE ACFT WHEN I STARTED THE JOB. I FOUND OUT ABOUT THE MISSING DOCUMENT AFTER THE COMPLETION OF THE JOB. I ALSO DID NOT DOCUMENT THE REMOVAL OF THE PREVIOUSLY MENTIONED ITEMS. THE EQUIP RACK #1 WAS REMOVED TO REPLACE A BAD YAW DAMPER COUPLER RACK CONNECTOR. THIS ALSO WAS NOT DOCUMENTED AS BEING CHANGED BEFORE I STARTED THE JOB. I INSTALLED THE EQUIP RACK #1 AND THE ELECTRONIC EQUIP FOR RACK #1 AND #2. I SIGNED THE WORK DONE AS REPLACED THE YAW DAMPER COUPLER CONNECTOR AND AN OPERATIONAL CHK ACCOMPLISHED OK. I DID NOT DOCUMENT THE INSTALLATION AND OPERATIONAL CHK OF THE EQUIP RACK #1 AND THE ELECTRONIC EQUIP ON RACKS #1 AND #2. THERE WERE 2 ELECTRONIC COMPONENTS (CABIN TEMP CTLR AND PRESSURE CTLR) ON THE RACK #1 THAT SHOULD HAVE HAD AN OPERATIONAL CHK BY THE ELECTRONIC TECHNICIAN. DUE TO MISCOM THIS WAS NOT DONE. ONLY A LOW LEVEL PITOT AND STATIC TEST WAS PERFORMED BY ME. A RADIO TECHNICIAN WAS REQUIRED FOR OPERATIONAL CHK OF THE ELECTRONIC EQUIP ON THE #1 AND #2 RACK. DUE TO THE COM PROB FROM THE RADIO TECHNICIAN TO THE ELECTRONIC TECHNICIAN THE CABIN TEMP CTLR AND THE PRESSURE CTLR OPERATIONAL CHK WAS NOT PERFORMED, RESULTING IN AN ACFT RETURN TO THE STATION FOR A MALFUNCTION OF THE PRESSURIZATION SYS. THE STATIC HOSE WAS NOT CONNECTED PROPERLY AND BECAME DISCONNECTED. ACCORDING TO OUR COMPANY MAINT MANUAL AND COMPANY STANDARD PRACTICE MANUALS AN INSPECTOR WAS REQUIRED TO CHK THE WORK AND THIS WAS NOT PERFORMED. THE SUPVRS ALSO DID NOT QUESTION THE LACK OF AN INSPECTION CHK. ANY OF WHICH WOULD HAVE FOUND THE MISINSTALLED PITOT HOSE TO THE PRESSURE CTLR, IMPROPER DOCUMENTATION OF THE ELECTRONIC EQUIP RACK AND ITS ELECTRONIC EQUIP.

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.