Narrative:

During routine job card for lubing horizontal stabilizer jack screw on feb/sun/02 on aircraft, I found that the screw was black in appearance and felt rough to the touch! I wrote it up and called XXXX, our controllers, and asked about the strange appearance of the jack screw. He did not know about the color or why the jack screw felt rough, but would get back to me on it. Well, I did not hear back from him and when morning came at about XA30, my manager asked me if the jack screw was lubed already or if I found it dry! I told him that I did lube it per the job card and it was dry when I found it! He then said that engineering sent him paperwork describing a mangenese phosphate coating that was put on. I read this document thoroughly, and did see where the coating is put on, but no description on appearance (document attached). But on page 2 there is a reference to the maintenance manual on the process of manganese phosphate coating (see attached document). Page 5 gives a description of the appearance which can be black or gray and shall not exhibit coarse crystalline texture! To me, this jack screw should not be in service. I did not read through this until my days off since I was not the one who released the airplane, but would appreciate if you can make sure that this airplane is safe. Callback conversation with reporter revealed the following information: the reporter stated the shop technician was sent to inspect the jack screw and found it ok for service. The reporter expressed concern that during this time the line maintenance controller, system engineer, and local management did not answer the request for help in finding documentation to determine if the jack screw was serviceable. The reporter said the lubrication job card was completed and the airplane returned to service.

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Original NASA ASRS Text

Title: A B737-300 DURING A HORIZ STABILIZER JACK SCREW LUBRICATION JOB CARD A TECHNICIAN DISCOVERED THE JACK SCREW BLACK IN COLOR AND ROUGH IN TEXTURE.

Narrative: DURING ROUTINE JOB CARD FOR LUBING HORIZ STABILIZER JACK SCREW ON FEB/SUN/02 ON ACFT, I FOUND THAT THE SCREW WAS BLACK IN APPEARANCE AND FELT ROUGH TO THE TOUCH! I WROTE IT UP AND CALLED XXXX, OUR CTLRS, AND ASKED ABOUT THE STRANGE APPEARANCE OF THE JACK SCREW. HE DID NOT KNOW ABOUT THE COLOR OR WHY THE JACK SCREW FELT ROUGH, BUT WOULD GET BACK TO ME ON IT. WELL, I DID NOT HEAR BACK FROM HIM AND WHEN MORNING CAME AT ABOUT XA30, MY MGR ASKED ME IF THE JACK SCREW WAS LUBED ALREADY OR IF I FOUND IT DRY! I TOLD HIM THAT I DID LUBE IT PER THE JOB CARD AND IT WAS DRY WHEN I FOUND IT! HE THEN SAID THAT ENGINEERING SENT HIM PAPERWORK DESCRIBING A MANGENESE PHOSPHATE COATING THAT WAS PUT ON. I READ THIS DOCUMENT THOROUGHLY, AND DID SEE WHERE THE COATING IS PUT ON, BUT NO DESCRIPTION ON APPEARANCE (DOCUMENT ATTACHED). BUT ON PAGE 2 THERE IS A REF TO THE MAINT MANUAL ON THE PROCESS OF MANGANESE PHOSPHATE COATING (SEE ATTACHED DOCUMENT). PAGE 5 GIVES A DESCRIPTION OF THE APPEARANCE WHICH CAN BE BLACK OR GRAY AND SHALL NOT EXHIBIT COARSE CRYSTALLINE TEXTURE! TO ME, THIS JACK SCREW SHOULD NOT BE IN SVC. I DID NOT READ THROUGH THIS UNTIL MY DAYS OFF SINCE I WAS NOT THE ONE WHO RELEASED THE AIRPLANE, BUT WOULD APPRECIATE IF YOU CAN MAKE SURE THAT THIS AIRPLANE IS SAFE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE SHOP TECHNICIAN WAS SENT TO INSPECT THE JACK SCREW AND FOUND IT OK FOR SERVICE. THE RPTR EXPRESSED CONCERN THAT DURING THIS TIME THE LINE MAINT CTLR, SYSTEM ENGINEER, AND LCL MANAGEMENT DID NOT ANSWER THE REQUEST FOR HELP IN FINDING DOCUMENTATION TO DETERMINE IF THE JACK SCREW WAS SERVICEABLE. THE RPTR SAID THE LUBRICATION JOB CARD WAS COMPLETED AND THE AIRPLANE RETURNED TO SERVICE.

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.