Narrative:

I was called about a standby rudder on light coming on during flight and it was not on while on the ground. I wanted to apply MEL 27-21 to the aircraft. I checked code to check that the rudder enhancement modification had been complied with and according to computer the modification has been complied with. The problem is that boeing service bulletin that is required to be complied with to use this MEL had not been complied with. This is the service bulletin for the rudder control rods not the rudder enhancement modification. To use this MEL both the enhancement modification as well as the control rod modification must be complied with. When checking in computer for compliance we track using aircraft change order numbers not the actual service bulletin numbers. I thought at the time that the only thing required for the MEL was the enhancement modification. This is not a very common MEL that I use. The MEL tells you to make sure the full enhancement modification has been completed and gives you the service bulletin number for the rudder control rods; why can't the MEL be corrected to read either both service bulletin numbers or use the wording for both but not the words for one and the service bulletin number for the other. Callback conversation with reporter revealed the following information: the reporter stated the MEL reference for deferral of the standby rudder light requires that 2 modifications be accomplished. The MEL gives the boeing service bulletin number for one modification and then describes the second modification using words; no service bulletin numbers. Checking with the maintenance computer only lists the modifications in the normal manner by aircraft change orders. An aircraft change order is the boeing service bulletin after engineering writes up the paperwork and job cards as is common practice throughout the industry. The MEL has been revised to show aircraft change orders to match the maintenance computer.

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Original NASA ASRS Text

Title: A B737-700 WITH A RPT OF RUDDER STANDBY LIGHT ON INFLT. ON ATTEMPTING TO DEFER THE ITEM PER THE MEL; FOUND CONFLICTING MEL WORDING AND NUMBERS FOR THE REQUIRED RUDDER MODIFICATIONS.

Narrative: I WAS CALLED ABOUT A STANDBY RUDDER ON LIGHT COMING ON DURING FLT AND IT WAS NOT ON WHILE ON THE GND. I WANTED TO APPLY MEL 27-21 TO THE ACFT. I CHKED CODE TO CHK THAT THE RUDDER ENHANCEMENT MODIFICATION HAD BEEN COMPLIED WITH AND ACCORDING TO COMPUTER THE MODIFICATION HAS BEEN COMPLIED WITH. THE PROB IS THAT BOEING SVC BULLETIN THAT IS REQUIRED TO BE COMPLIED WITH TO USE THIS MEL HAD NOT BEEN COMPLIED WITH. THIS IS THE SVC BULLETIN FOR THE RUDDER CTL RODS NOT THE RUDDER ENHANCEMENT MODIFICATION. TO USE THIS MEL BOTH THE ENHANCEMENT MODIFICATION AS WELL AS THE CTL ROD MODIFICATION MUST BE COMPLIED WITH. WHEN CHKING IN COMPUTER FOR COMPLIANCE WE TRACK USING ACFT CHANGE ORDER NUMBERS NOT THE ACTUAL SVC BULLETIN NUMBERS. I THOUGHT AT THE TIME THAT THE ONLY THING REQUIRED FOR THE MEL WAS THE ENHANCEMENT MODIFICATION. THIS IS NOT A VERY COMMON MEL THAT I USE. THE MEL TELLS YOU TO MAKE SURE THE FULL ENHANCEMENT MODIFICATION HAS BEEN COMPLETED AND GIVES YOU THE SVC BULLETIN NUMBER FOR THE RUDDER CTL RODS; WHY CAN'T THE MEL BE CORRECTED TO READ EITHER BOTH SVC BULLETIN NUMBERS OR USE THE WORDING FOR BOTH BUT NOT THE WORDS FOR ONE AND THE SVC BULLETIN NUMBER FOR THE OTHER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE MEL REF FOR DEFERRAL OF THE STANDBY RUDDER LIGHT REQUIRES THAT 2 MODIFICATIONS BE ACCOMPLISHED. THE MEL GIVES THE BOEING SVC BULLETIN NUMBER FOR ONE MODIFICATION AND THEN DESCRIBES THE SECOND MODIFICATION USING WORDS; NO SVC BULLETIN NUMBERS. CHKING WITH THE MAINT COMPUTER ONLY LISTS THE MODIFICATIONS IN THE NORMAL MANNER BY ACFT CHANGE ORDERS. AN ACFT CHANGE ORDER IS THE BOEING SVC BULLETIN AFTER ENGINEERING WRITES UP THE PAPERWORK AND JOB CARDS AS IS COMMON PRACTICE THROUGHOUT THE INDUSTRY. THE MEL HAS BEEN REVISED TO SHOW ACFT CHANGE ORDERS TO MATCH THE MAINT COMPUTER.

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.