Narrative:

An experienced avionics technician called for an MEL for both engine's 'a' ignition system inoperative; circuit breaker was popped. I had never applied this MEL for both engines before. I was reading through the MEL while addressing other problems on other aircraft on a very busy morning. There is a note on the MEL that this circuit breaker affects both 'a' system. I neglected to interpretation '2 installed 1 required' as referring to only system 'a' not both system. The technician was also rushed as aircraft was at push. We both agreed the MEL applied. Aircraft flew to ZZZ where the next crew pointed out the error which at that time was obvious to me that the wrong MEL was applied. I explained my mistake to the next shift who called contract maintenance. Maintenance performed an operations check for both 'a' system and cleared the MEL. The original technician who placed the MEL in ZZZ1 had reset the circuit breaker but did not have time for an operations check. The circuit breaker has not popped since it left ZZZ1. Operation was normal from the outset. Aircraft had no further incident of 'a' ignition problems nor previous history.

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Original NASA ASRS Text

Title: AN A320 WAS DISPATCHED WITH BOTH L AND R 'A' SYS IGNITION SYS INOP IN CONFLICT WITH THE MEL.

Narrative: AN EXPERIENCED AVIONICS TECHNICIAN CALLED FOR AN MEL FOR BOTH ENG'S 'A' IGNITION SYS INOP; CIRCUIT BREAKER WAS POPPED. I HAD NEVER APPLIED THIS MEL FOR BOTH ENGS BEFORE. I WAS READING THROUGH THE MEL WHILE ADDRESSING OTHER PROBS ON OTHER ACFT ON A VERY BUSY MORNING. THERE IS A NOTE ON THE MEL THAT THIS CIRCUIT BREAKER AFFECTS BOTH 'A' SYS. I NEGLECTED TO INTERP '2 INSTALLED 1 REQUIRED' AS REFERRING TO ONLY SYS 'A' NOT BOTH SYS. THE TECHNICIAN WAS ALSO RUSHED AS ACFT WAS AT PUSH. WE BOTH AGREED THE MEL APPLIED. ACFT FLEW TO ZZZ WHERE THE NEXT CREW POINTED OUT THE ERROR WHICH AT THAT TIME WAS OBVIOUS TO ME THAT THE WRONG MEL WAS APPLIED. I EXPLAINED MY MISTAKE TO THE NEXT SHIFT WHO CALLED CONTRACT MAINT. MAINT PERFORMED AN OPS CHK FOR BOTH 'A' SYS AND CLRED THE MEL. THE ORIGINAL TECHNICIAN WHO PLACED THE MEL IN ZZZ1 HAD RESET THE CIRCUIT BREAKER BUT DID NOT HAVE TIME FOR AN OPS CHK. THE CIRCUIT BREAKER HAS NOT POPPED SINCE IT LEFT ZZZ1. OP WAS NORMAL FROM THE OUTSET. ACFT HAD NO FURTHER INCIDENT OF 'A' IGNITION PROBS NOR PREVIOUS HISTORY.

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.