Narrative:

I needed to defer a right engine reverser unlock indication light. MEL xx-2 is for engine reverser unlock light indication system. The maintenance procedure for this MEL tells you to make sure latch indication arm (at engine) is not extended prior to each departure. This particular engine reverser does not have this indication arm. It has hydraulic latches with no other visual indicators. MEL xx-2 misleads me to think no other maintenance procedure needs to be completed except to see that reverser is checked for proper stowage in the retracted position as stated in MEL xx-2 remarks and exceptions. MEL xx-1A is a deferral for the entire thrust reverser (for whatever problem it might have). MEL xx-1A maintenance procedure refers you to a t-function (technical function) for a mechanic to reactivate thrust reverser system. With the hydraulic latches that this aircraft has, MEL xx-1 tells you to verify upper and lower doors are faired at leading edges, verify over-center links are over center, open the affected thrust reverser control valve door and place handle in dump position and pin and lock it. Also to open and collar affected thrust reverser accumulator low light circuit breaker. The MEL that I used for an unlock light (xx-2) problem should refer you to the above procedure or to MEL xx-1 if the airplane is equipped with hydraulic latches. The problem being that without a referral on MEL xx-2 you don't think you have to do any deactivation of the thrust reverser, if it has hydraulic latches. It should be an MEL that says aircraft with hydraulic latches refer to MEL xx-1 for deactivation.

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Original NASA ASRS Text

Title: AN MD88 WAS DISPATCHED IN NON COMPLIANCE WITH A #2 ENG THRUST REVERSER UNLOCK INDICATION LIGHT SYS DEFERRED PER THE MEL BUT THE SPECIAL PROCS TO MECHANICALLY LOCK THE REVERSER WERE NOT ACCOMPLISHED.

Narrative: I NEEDED TO DEFER A R ENG REVERSER UNLOCK INDICATION LIGHT. MEL XX-2 IS FOR ENG REVERSER UNLOCK LIGHT INDICATION SYS. THE MAINT PROC FOR THIS MEL TELLS YOU TO MAKE SURE LATCH INDICATION ARM (AT ENG) IS NOT EXTENDED PRIOR TO EACH DEP. THIS PARTICULAR ENG REVERSER DOES NOT HAVE THIS INDICATION ARM. IT HAS HYD LATCHES WITH NO OTHER VISUAL INDICATORS. MEL XX-2 MISLEADS ME TO THINK NO OTHER MAINT PROC NEEDS TO BE COMPLETED EXCEPT TO SEE THAT REVERSER IS CHKED FOR PROPER STOWAGE IN THE RETRACTED POS AS STATED IN MEL XX-2 REMARKS AND EXCEPTIONS. MEL XX-1A IS A DEFERRAL FOR THE ENTIRE THRUST REVERSER (FOR WHATEVER PROB IT MIGHT HAVE). MEL XX-1A MAINT PROC REFERS YOU TO A T-FUNCTION (TECHNICAL FUNCTION) FOR A MECH TO REACTIVATE THRUST REVERSER SYS. WITH THE HYD LATCHES THAT THIS ACFT HAS, MEL XX-1 TELLS YOU TO VERIFY UPPER AND LOWER DOORS ARE FAIRED AT LEADING EDGES, VERIFY OVER-CTR LINKS ARE OVER CTR, OPEN THE AFFECTED THRUST REVERSER CTL VALVE DOOR AND PLACE HANDLE IN DUMP POS AND PIN AND LOCK IT. ALSO TO OPEN AND COLLAR AFFECTED THRUST REVERSER ACCUMULATOR LOW LIGHT CIRCUIT BREAKER. THE MEL THAT I USED FOR AN UNLOCK LIGHT (XX-2) PROB SHOULD REFER YOU TO THE ABOVE PROC OR TO MEL XX-1 IF THE AIRPLANE IS EQUIPPED WITH HYD LATCHES. THE PROB BEING THAT WITHOUT A REFERRAL ON MEL XX-2 YOU DON'T THINK YOU HAVE TO DO ANY DEACTIVATION OF THE THRUST REVERSER, IF IT HAS HYD LATCHES. IT SHOULD BE AN MEL THAT SAYS ACFT WITH HYD LATCHES REFER TO MEL XX-1 FOR DEACTIVATION.

Data retrieved from NASA's ASRS site as of July 2007 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.