Narrative:

Aircraft arrived at the facility on a ferry permit for inoperative flaps. The night shift troubleshot and determined one flap actuator required replacement. Day shift took over and determined that both actuators required replacement. Both actuators were replaced, the flaps rigged and operations checked per the manual. During this entire procedure, a hydraulic mule was used to provide hydraulic pressure. The aircraft was cleaned, paperwork completed and returned to service. Crew reported that upon gear retraction after takeoff, the low pressure light (hydraulic) illuminated and the nose gear did not fully retract. The gear was selected down and aircraft made an uneventful landing. Investigation disclosed the hydraulic reservoir servicing was low. Reservoir resvced per the maintenance manual and all system operated normally. The hydraulic mule has a 2 position valve to select aircraft reservoir or mule reservoir. During troubleshooting and rigging of the flaps, the valve was in the mule reservoir position. When used in this position, hydraulic fluid will xfer from the aircraft to the mule. Maintenance did not rechk reservoir servicing before releasing aircraft and the flight crew did not see it on their walkaround which resulted in an aircraft being released with an improperly svced hydraulic reservoir. All hydraulic mules have been labeled to check aircraft reservoir after using the mule and a memo released to maintenance personnel. The manufacturer of the mule has been contacted to see why this happens and if it can be prevented.

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Original NASA ASRS Text

Title: A GULFSTREAM II WAS DISPATCHED IN NON COMPLIANCE AFTER MAINT WITH INADEQUATE HYD FLUID QUANTITY.

Narrative: ACFT ARRIVED AT THE FACILITY ON A FERRY PERMIT FOR INOP FLAPS. THE NIGHT SHIFT TROUBLESHOT AND DETERMINED ONE FLAP ACTUATOR REQUIRED REPLACEMENT. DAY SHIFT TOOK OVER AND DETERMINED THAT BOTH ACTUATORS REQUIRED REPLACEMENT. BOTH ACTUATORS WERE REPLACED, THE FLAPS RIGGED AND OPS CHKED PER THE MANUAL. DURING THIS ENTIRE PROC, A HYD MULE WAS USED TO PROVIDE HYD PRESSURE. THE ACFT WAS CLEANED, PAPERWORK COMPLETED AND RETURNED TO SVC. CREW RPTED THAT UPON GEAR RETRACTION AFTER TKOF, THE LOW PRESSURE LIGHT (HYD) ILLUMINATED AND THE NOSE GEAR DID NOT FULLY RETRACT. THE GEAR WAS SELECTED DOWN AND ACFT MADE AN UNEVENTFUL LNDG. INVESTIGATION DISCLOSED THE HYD RESERVOIR SVCING WAS LOW. RESERVOIR RESVCED PER THE MAINT MANUAL AND ALL SYS OPERATED NORMALLY. THE HYD MULE HAS A 2 POS VALVE TO SELECT ACFT RESERVOIR OR MULE RESERVOIR. DURING TROUBLESHOOTING AND RIGGING OF THE FLAPS, THE VALVE WAS IN THE MULE RESERVOIR POS. WHEN USED IN THIS POS, HYD FLUID WILL XFER FROM THE ACFT TO THE MULE. MAINT DID NOT RECHK RESERVOIR SVCING BEFORE RELEASING ACFT AND THE FLC DID NOT SEE IT ON THEIR WALKAROUND WHICH RESULTED IN AN ACFT BEING RELEASED WITH AN IMPROPERLY SVCED HYD RESERVOIR. ALL HYD MULES HAVE BEEN LABELED TO CHK ACFT RESERVOIR AFTER USING THE MULE AND A MEMO RELEASED TO MAINT PERSONNEL. THE MANUFACTURER OF THE MULE HAS BEEN CONTACTED TO SEE WHY THIS HAPPENS AND IF IT CAN BE PREVENTED.

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.