Narrative:

While operating as air carrier flight abcd from ZZZ to XXX on apr/xa/01, upon completing our preflight duties, a water leak was detected around the faucet in the forward lavatory. Trying to isolate the leak, the flight engineer inadvertently opened the drain valve. The ground crew advised us of draining water. After research and consultation with our maintenance coordinator, the drain was closed and the supply line valve under the sink was closed. The leak stopped. The flight engineer advised the captain and I that the leak was a non-airworthy item that could be flight crew placarded and called into maintenance control en route to XXX. Upon arrival in XXX, the supply line valve was cycled by the crew and the leak had seated itself. No logbook entry was ever made. Days later, after an inquiry by the chief pilot to know the reason for our delay, investigation revealed it could have been determined that the leak was an item in the maintenance deferral manual and should have been an airworthy write-up, potable water system secured by local maintenance and dispatch approval required. Contributing to the error was the fact that the flight engineer, although relatively new, was very convincing to be correct in his interpretation of the situation but should have been questioned by either the captain or myself. I feel it was a CRM break. Although a new pilot should be trusted, he should also be closely crosschecked by the rest of the crew. I feel I may have gotten a false sense of security that things were being done correctly by the fact that the captain, had consulted with maintenance.

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Original NASA ASRS Text

Title: A B727-200 WAS DISPATCHED IN NON COMPLIANCE WITH A LAVATORY SINK LEAK NOT ENTERED IN THE LOGBOOK OR DEFERRED.

Narrative: WHILE OPERATING AS ACR FLT ABCD FROM ZZZ TO XXX ON APR/XA/01, UPON COMPLETING OUR PREFLT DUTIES, A WATER LEAK WAS DETECTED AROUND THE FAUCET IN THE FORWARD LAVATORY. TRYING TO ISOLATE THE LEAK, THE FE INADVERTENTLY OPENED THE DRAIN VALVE. THE GND CREW ADVISED US OF DRAINING WATER. AFTER RESEARCH AND CONSULTATION WITH OUR MAINT COORDINATOR, THE DRAIN WAS CLOSED AND THE SUPPLY LINE VALVE UNDER THE SINK WAS CLOSED. THE LEAK STOPPED. THE FE ADVISED THE CAPT AND I THAT THE LEAK WAS A NON-AIRWORTHY ITEM THAT COULD BE FLC PLACARDED AND CALLED INTO MAINT CTL ENRTE TO XXX. UPON ARR IN XXX, THE SUPPLY LINE VALVE WAS CYCLED BY THE CREW AND THE LEAK HAD SEATED ITSELF. NO LOGBOOK ENTRY WAS EVER MADE. DAYS LATER, AFTER AN INQUIRY BY THE CHIEF PLT TO KNOW THE REASON FOR OUR DELAY, INVESTIGATION REVEALED IT COULD HAVE BEEN DETERMINED THAT THE LEAK WAS AN ITEM IN THE MAINT DEFERRAL MANUAL AND SHOULD HAVE BEEN AN AIRWORTHY WRITE-UP, POTABLE WATER SYS SECURED BY LCL MAINT AND DISPATCH APPROVAL REQUIRED. CONTRIBUTING TO THE ERROR WAS THE FACT THAT THE FE, ALTHOUGH RELATIVELY NEW, WAS VERY CONVINCING TO BE CORRECT IN HIS INTERP OF THE SIT BUT SHOULD HAVE BEEN QUESTIONED BY EITHER THE CAPT OR MYSELF. I FEEL IT WAS A CRM BREAK. ALTHOUGH A NEW PLT SHOULD BE TRUSTED, HE SHOULD ALSO BE CLOSELY XCHKED BY THE REST OF THE CREW. I FEEL I MAY HAVE GOTTEN A FALSE SENSE OF SECURITY THAT THINGS WERE BEING DONE CORRECTLY BY THE FACT THAT THE CAPT, HAD CONSULTED WITH MAINT.

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.