Narrative:

Approximately 10 mins prior to push; crew called to inform us there was an MEL on the aircraft for a missing reverser korry light. I then went to parts; retrieved one and went to the gate to clear the MEL. I told the captain 'I couldn't believe the MEL hadn't been cleared.' I went to operations check the reverser. The captain told me he would do it. I cleared the MEL and left the aircraft. When I got back to the shop I noticed the paperwork had XXXX; that's when I realized the reverser was locked out. I then called to correct the problem. Callback conversation with reporter revealed the following information: reporter stated when his lead sent him out to replace the thrust reverser korry light in the cockpit; he did not even realize that the reverser itself was physically deactivated. In fact; both he and the pilot were both unaware of the deactivation. When he returned to the line office; the lead had just finished reading the MEL procedure that requires a reverser check and that also required the reverser lockout to be removed; which in this case is installed on the inboard and outboard sides of the engine. Reporter also stated he had already cleared the MEL on the basis that the light was the only issue and the aircraft had already left. He and the lead called dispatch to have the flight crew be made aware of the locked-out reverser. The flight continued on to original destination without incident.

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Original NASA ASRS Text

Title: A B737-500 MEL WAS CLEARED AND ACFT RELEASED FOR SERVICE AFTER THRUST REVERSER KORRY LIGHT IN COCKPIT WAS REPLACED. REVERSER STILL DEACTIVATED. LOCKOUT NOT REMOVED.

Narrative: APPROX 10 MINS PRIOR TO PUSH; CREW CALLED TO INFORM US THERE WAS AN MEL ON THE ACFT FOR A MISSING REVERSER KORRY LIGHT. I THEN WENT TO PARTS; RETRIEVED ONE AND WENT TO THE GATE TO CLR THE MEL. I TOLD THE CAPT 'I COULDN'T BELIEVE THE MEL HADN'T BEEN CLRED.' I WENT TO OPS CHK THE REVERSER. THE CAPT TOLD ME HE WOULD DO IT. I CLRED THE MEL AND LEFT THE ACFT. WHEN I GOT BACK TO THE SHOP I NOTICED THE PAPERWORK HAD XXXX; THAT'S WHEN I REALIZED THE REVERSER WAS LOCKED OUT. I THEN CALLED TO CORRECT THE PROB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED WHEN HIS LEAD SENT HIM OUT TO REPLACE THE THRUST REVERSER KORRY LIGHT IN THE COCKPIT; HE DID NOT EVEN REALIZE THAT THE REVERSER ITSELF WAS PHYSICALLY DEACTIVATED. IN FACT; BOTH HE AND THE PILOT WERE BOTH UNAWARE OF THE DEACTIVATION. WHEN HE RETURNED TO THE LINE OFFICE; THE LEAD HAD JUST FINISHED READING THE MEL PROCEDURE THAT REQUIRES A REVERSER CHECK AND THAT ALSO REQUIRED THE REVERSER LOCKOUT TO BE REMOVED; WHICH IN THIS CASE IS INSTALLED ON THE INBOARD AND OUTBOARD SIDES OF THE ENGINE. REPORTER ALSO STATED HE HAD ALREADY CLEARED THE MEL ON THE BASIS THAT THE LIGHT WAS THE ONLY ISSUE AND THE ACFT HAD ALREADY LEFT. HE AND THE LEAD CALLED DISPATCH TO HAVE THE FLIGHT CREW BE MADE AWARE OF THE LOCKED-OUT REVERSER. THE FLIGHT CONTINUED ON TO ORIGINAL DESTINATION WITHOUT INCIDENT.

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.