Narrative:

Maintenance called requesting to put the right inboard landing light on aircraft X on placard. I asked the mechanic if all the rest of the landing lights were working and was told that they were. So I went ahead and issued the placard 33-08-1RI 'right-hand inboard landing light inoperative.' after the aircraft was en route to ZZZ; I found out that the left inboard landing light was on placard as well. MEL 33-08 allows for 1 landing light to be inoperative on each side provided that one of the remaining operating lights is in a fixed position; which it was not. Generally I check the placard list in the computer system program before issuing a placard; but at this time I did not have the program session up on my computer due to the previous call requesting that I change the aircraft number on a computer system entry that had been made in error on aircraft X so I just took the mechanic's word that the remaining landing lights on aircraft X were working. When notifying dispatch of putting the right landing light on placard he asked me if all the rest of the landing lights were working and I told him the same thing that the mechanic had told me; that 'all the rest were working fine.'

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Original NASA ASRS Text

Title: B737-300 WAS DISPATCHED WITH 2 INBOARD LNDG LIGHTS INOP IN CONFLICT WITH THE MEL.

Narrative: MAINT CALLED REQUESTING TO PUT THE R INBOARD LNDG LIGHT ON ACFT X ON PLACARD. I ASKED THE MECH IF ALL THE REST OF THE LNDG LIGHTS WERE WORKING AND WAS TOLD THAT THEY WERE. SO I WENT AHEAD AND ISSUED THE PLACARD 33-08-1RI 'R-HAND INBOARD LNDG LIGHT INOP.' AFTER THE ACFT WAS ENRTE TO ZZZ; I FOUND OUT THAT THE L INBOARD LNDG LIGHT WAS ON PLACARD AS WELL. MEL 33-08 ALLOWS FOR 1 LNDG LIGHT TO BE INOP ON EACH SIDE PROVIDED THAT ONE OF THE REMAINING OPERATING LIGHTS IS IN A FIXED POS; WHICH IT WAS NOT. GENERALLY I CHK THE PLACARD LIST IN THE COMPUTER SYS PROGRAM BEFORE ISSUING A PLACARD; BUT AT THIS TIME I DID NOT HAVE THE PROGRAM SESSION UP ON MY COMPUTER DUE TO THE PREVIOUS CALL REQUESTING THAT I CHANGE THE ACFT NUMBER ON A COMPUTER SYS ENTRY THAT HAD BEEN MADE IN ERROR ON ACFT X SO I JUST TOOK THE MECH'S WORD THAT THE REMAINING LNDG LIGHTS ON ACFT X WERE WORKING. WHEN NOTIFYING DISPATCH OF PUTTING THE RIGHT LNDG LIGHT ON PLACARD HE ASKED ME IF ALL THE REST OF THE LNDG LIGHTS WERE WORKING AND I TOLD HIM THE SAME THING THAT THE MECH HAD TOLD ME; THAT 'ALL THE REST WERE WORKING FINE.'

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.