Narrative:

Just prior to push; flight crew called in first officer's air data failed on gate. Troubleshoot per fim and found right side air data module had failed. With removal/installation procedure in hand; I proceeded to gate for repair. During the removal; I asked my lead technician to verify if low level leak check and rii was required; and I was informed via radio that they were not. The entry for the repair was accomplished and the CAT ii/III tests were deferred in accordance with MEL. The aircraft departed and continued in service. The amm did not have any additional references for quick disconnect fittings and rii requirements. In september; in reviewing the gmm and rii requirements; I returned to the flight line from nearly a yr of out of service/utility crew assignment recently; to bring myself up to date. I discovered the gmm required an rii inspection of the quick disconnect fitting. I informed the on-shift supervisor of the error and the station maintenance operations room to inform maintenance control of the error and to have an entry made to inspect and rii the fitting at next available maintenance station. To make sure the rii required installation of the quick disconnect fitting does not get overlooked; an additional page or note entry under the manual step to either get the rii or verify the gmm rii requirements need to be reviewed so it does not get overlooked as in this case. Callback conversation with reporter revealed the following information: reporter stated the air data module takes raw data from pitot tube input; using a piezo type electronic input and processor in the adm; and converts the information into digital signals for the adiru's; symbol generators and cockpit displays. There is one adm for each pitot tube on the B737-800's. Reporter stated some type of reference should be noted in the amm regarding rii's; or instructs mechanics to reference their general maintenance manuals; whenever an rii may be required. Especially; when the rii is not referenced specifically; in the procedure that mechanic is using to replace a part.

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Original NASA ASRS Text

Title: TWO DAYS AFTER REPLACING A FAILED AIR DATA MODULE ON A B737-800; A LINE MECHANIC REALIZES THE RII INSPECTION WAS NOT ACCOMPLISHED ON THE ADM QUICK DISCONNECT FITTING. NO RII REFERENCE IN MAINT MANUAL.

Narrative: JUST PRIOR TO PUSH; FLT CREW CALLED IN FO'S AIR DATA FAILED ON GATE. TROUBLESHOOT PER FIM AND FOUND R SIDE AIR DATA MODULE HAD FAILED. WITH REMOVAL/INSTALLATION PROC IN HAND; I PROCEEDED TO GATE FOR REPAIR. DURING THE REMOVAL; I ASKED MY LEAD TECHNICIAN TO VERIFY IF LOW LEVEL LEAK CHK AND RII WAS REQUIRED; AND I WAS INFORMED VIA RADIO THAT THEY WERE NOT. THE ENTRY FOR THE REPAIR WAS ACCOMPLISHED AND THE CAT II/III TESTS WERE DEFERRED IN ACCORDANCE WITH MEL. THE ACFT DEPARTED AND CONTINUED IN SVC. THE AMM DID NOT HAVE ANY ADDITIONAL REFS FOR QUICK DISCONNECT FITTINGS AND RII REQUIREMENTS. IN SEPTEMBER; IN REVIEWING THE GMM AND RII REQUIREMENTS; I RETURNED TO THE FLT LINE FROM NEARLY A YR OF OUT OF SVC/UTILITY CREW ASSIGNMENT RECENTLY; TO BRING MYSELF UP TO DATE. I DISCOVERED THE GMM REQUIRED AN RII INSPECTION OF THE QUICK DISCONNECT FITTING. I INFORMED THE ON-SHIFT SUPVR OF THE ERROR AND THE STATION MAINT OPS ROOM TO INFORM MAINT CTL OF THE ERROR AND TO HAVE AN ENTRY MADE TO INSPECT AND RII THE FITTING AT NEXT AVAILABLE MAINT STATION. TO MAKE SURE THE RII REQUIRED INSTALLATION OF THE QUICK DISCONNECT FITTING DOES NOT GET OVERLOOKED; AN ADDITIONAL PAGE OR NOTE ENTRY UNDER THE MANUAL STEP TO EITHER GET THE RII OR VERIFY THE GMM RII REQUIREMENTS NEED TO BE REVIEWED SO IT DOES NOT GET OVERLOOKED AS IN THIS CASE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED THE AIR DATA MODULE TAKES RAW DATA FROM PITOT TUBE INPUT; USING A PIEZO TYPE ELECTRONIC INPUT AND PROCESSOR IN THE ADM; AND CONVERTS THE INFO INTO DIGITAL SIGNALS FOR THE ADIRU'S; SYMBOL GENERATORS AND COCKPIT DISPLAYS. THERE IS ONE ADM FOR EACH PITOT TUBE ON THE B737-800'S. REPORTER STATED SOME TYPE OF REFERENCE SHOULD BE NOTED IN THE AMM REGARDING RII'S; OR INSTRUCTS MECHANICS TO REFERENCE THEIR GENERAL MAINT MANUALS; WHENEVER AN RII MAY BE REQUIRED. ESPECIALLY; WHEN THE RII IS NOT REFERENCED SPECIFICALLY; IN THE PROCEDURE THAT MECHANIC IS USING TO REPLACE A PART.

Data retrieved from NASA's ASRS site as of May 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.