Narrative:

Aircraft X arrived ZZZ approximately XA30 with a leak in the first class lavatory water system. ZZZ3 determined that a lavatory without a working water system was good enough for the use of a flight crew on a 5 hour flight from ZZZ1 to ZZZ2. Xa message allows for use of aircraft if lavatory must not be used for passenger, but is available for crew use. This would seem to cover such things as lighting, return to seat signs, lack of water in the sink, no smoke detectors, and things of a like nature. It appears to me that this loop hole was exploited. ZZZ3 was informed and in a 3-WAY call with maintenance someone told me that passenger were not able to use the lavatory because it might become unsanitary. ZZZ3 seems like a bad way to run an MEL system.

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Original NASA ASRS Text

Title: A B767-300 CAPT BELIEVES CONTINUED DEFERRAL OF THE FIRST CLASS LAVATORY DUE TO WATER LEAK AND LIMITED TO FLC ONLY IS NOT CORRECT INTERP OF MEL REQUIREMENTS.

Narrative: ACFT X ARRIVED ZZZ APPROX XA30 WITH A LEAK IN THE FIRST CLASS LAVATORY WATER SYS. ZZZ3 DETERMINED THAT A LAVATORY WITHOUT A WORKING WATER SYS WAS GOOD ENOUGH FOR THE USE OF A FLC ON A 5 HR FLT FROM ZZZ1 TO ZZZ2. XA MESSAGE ALLOWS FOR USE OF ACFT IF LAVATORY MUST NOT BE USED FOR PAX, BUT IS AVAILABLE FOR CREW USE. THIS WOULD SEEM TO COVER SUCH THINGS AS LIGHTING, RETURN TO SEAT SIGNS, LACK OF WATER IN THE SINK, NO SMOKE DETECTORS, AND THINGS OF A LIKE NATURE. IT APPEARS TO ME THAT THIS LOOP HOLE WAS EXPLOITED. ZZZ3 WAS INFORMED AND IN A 3-WAY CALL WITH MAINT SOMEONE TOLD ME THAT PAX WERE NOT ABLE TO USE THE LAVATORY BECAUSE IT MIGHT BECOME UNSANITARY. ZZZ3 SEEMS LIKE A BAD WAY TO RUN AN MEL SYS.

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.