Narrative:

On 00/07/fri, I replaced the check valve for the directional control valve for the rudder. I have since become aware of the fact that it was installed backwards. As for the sign off, it was leaked checked and I inadvertently also wrote operations check good. Callback conversation with reporter revealed the following information: the reporter stated when he was given the assignment to replace the check valve an old time employee gave me the check valve with a short piece of tubing attached and said, 'it goes in just like this'. The reporter checked the mntnc manual, but no procedure described the valve replacement. The reporter said the valve was replaced and on an operation check of the rudder locked up with no movement. The reporter stated the check valve was reversed and operation was normal. The reporter said several things were discovered, the valve body had no cast in direction of flow arrow and the tube fittings were the same on both ends of the valve. The reporter stated the mntnc manual had no procedure for this valve replacement. The reporter said this whole task was not 'murphy proof'. The reporter said corrections for revising the mntnc manual and all class 1 documents pertaining to this check valve were submitted to engineering.

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Original NASA ASRS Text

Title: AN MD80 RUDDER CTL VALVE HYD CHK VALVE WAS INSTALLED BACKWARDS LOCKING UP THE RUDDER ON GND TEST.

Narrative: ON 00/07/FRI, I REPLACED THE CHK VALVE FOR THE DIRECTIONAL CTL VALVE FOR THE RUDDER. I HAVE SINCE BECOME AWARE OF THE FACT THAT IT WAS INSTALLED BACKWARDS. AS FOR THE SIGN OFF, IT WAS LEAKED CHKED AND I INADVERTENTLY ALSO WROTE OPS CHK GOOD. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED WHEN HE WAS GIVEN THE ASSIGNMENT TO REPLACE THE CHK VALVE AN OLD TIME EMPLOYEE GAVE ME THE CHK VALVE WITH A SHORT PIECE OF TUBING ATTACHED AND SAID, 'IT GOES IN JUST LIKE THIS'. THE RPTR CHKED THE MNTNC MANUAL, BUT NO PROC DESCRIBED THE VALVE REPLACEMENT. THE RPTR SAID THE VALVE WAS REPLACED AND ON AN OP CHK OF THE RUDDER LOCKED UP WITH NO MOVEMENT. THE RPTR STATED THE CHK VALVE WAS REVERSED AND OP WAS NORMAL. THE RPTR SAID SEVERAL THINGS WERE DISCOVERED, THE VALVE BODY HAD NO CAST IN DIRECTION OF FLOW ARROW AND THE TUBE FITTINGS WERE THE SAME ON BOTH ENDS OF THE VALVE. THE RPTR STATED THE MNTNC MANUAL HAD NO PROC FOR THIS VALVE REPLACEMENT. THE RPTR SAID THIS WHOLE TASK WAS NOT 'MURPHY PROOF'. THE RPTR SAID CORRECTIONS FOR REVISING THE MNTNC MANUAL AND ALL CLASS 1 DOCUMENTS PERTAINING TO THIS CHK VALVE WERE SUBMITTED TO ENGINEERING.

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.