Narrative:

Jun/thu/02, I replaced the #3 brake assembly on aircraft X during its overnight visit to ZZZ. It departed ZZZ and flew to ZZZ1 uneventfully. It departed ZZZ1 and upon gear retraction had a gear unsafe indication. Returning to ZZZ1, the hydraulic pump handle was found in the pump that's used to change the brake accumulator. I used the handle to charge the brake system for leak checking the replaced brake assembly in ZZZ. I do not recall leaving the handle in the pump. It has a storage point in the right gear well where the pump is. If the handle is left in the pump, it prevents the gear door from closing on gear retraction. I believe the handle was in the storage facility when the aircraft departed ZZZ and was used at some other time. It's common practice for other than maintenance personnel to use the handle for restoring brake pressure prior to aircraft movement. Callback conversation with reporter revealed the following information: the reporter stated that after pressurizing the brake accumulator using the manual pump the handle was removed and stowed. The reporter said the airplane departed with no landing gear or landing gear door problem. The reporter stated it is common for technicians and crew members to use the manual pump to charge the brake system accumulator prior to departure. The reporter said this is what must have happened and the handle was left in the pump causing a landing gear door warning.

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Original NASA ASRS Text

Title: A DEHAVILLAND DASH 8 WAS DISPATCHED IN NON COMPLIANCE WITH THE AUX HYD MANUAL PUMP HANDLE LEFT IN THE PUMP INTERFERING WITH THE MAIN GEAR DOOR.

Narrative: JUN/THU/02, I REPLACED THE #3 BRAKE ASSEMBLY ON ACFT X DURING ITS OVERNIGHT VISIT TO ZZZ. IT DEPARTED ZZZ AND FLEW TO ZZZ1 UNEVENTFULLY. IT DEPARTED ZZZ1 AND UPON GEAR RETRACTION HAD A GEAR UNSAFE INDICATION. RETURNING TO ZZZ1, THE HYD PUMP HANDLE WAS FOUND IN THE PUMP THAT'S USED TO CHANGE THE BRAKE ACCUMULATOR. I USED THE HANDLE TO CHARGE THE BRAKE SYS FOR LEAK CHKING THE REPLACED BRAKE ASSEMBLY IN ZZZ. I DO NOT RECALL LEAVING THE HANDLE IN THE PUMP. IT HAS A STORAGE POINT IN THE R GEAR WELL WHERE THE PUMP IS. IF THE HANDLE IS LEFT IN THE PUMP, IT PREVENTS THE GEAR DOOR FROM CLOSING ON GEAR RETRACTION. I BELIEVE THE HANDLE WAS IN THE STORAGE FACILITY WHEN THE ACFT DEPARTED ZZZ AND WAS USED AT SOME OTHER TIME. IT'S COMMON PRACTICE FOR OTHER THAN MAINT PERSONNEL TO USE THE HANDLE FOR RESTORING BRAKE PRESSURE PRIOR TO ACFT MOVEMENT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT AFTER PRESSURIZING THE BRAKE ACCUMULATOR USING THE MANUAL PUMP THE HANDLE WAS REMOVED AND STOWED. THE RPTR SAID THE AIRPLANE DEPARTED WITH NO LNDG GEAR OR LNDG GEAR DOOR PROB. THE RPTR STATED IT IS COMMON FOR TECHNICIANS AND CREW MEMBERS TO USE THE MANUAL PUMP TO CHARGE THE BRAKE SYS ACCUMULATOR PRIOR TO DEP. THE RPTR SAID THIS IS WHAT MUST HAVE HAPPENED AND THE HANDLE WAS LEFT IN THE PUMP CAUSING A LNDG GEAR DOOR WARNING.

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.