Service difficulty report · Drive Shaft · Lear 60LEAR

Difficulty date
September 17, 2025
Submitted
September 19, 2025
Operation
General aviation
Aircraft
N491CP
Make and model
Lear 60LEAR
Aircraft serial
60122
Aircraft time
9,496 hours, 4,580 cycles
Part
Drive Shaft
Condition
Sheared
Location
Hyd Pump
Component
Pump · Parkerhanfin
Component part number
66070661
Stage of operation
CL
How discovered
O
Nature of condition
J
Precautionary procedure
A

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

ON 9/17/2025, LEAR 60 N491CP DEPARTED KSNA HEADING TO KSAT WHEN THE CREW NOTICED THE RH ENGINE LOW HYDRAULIC PRESSURE LIGHT COME ON. THE PRESSURE INDICATOR WAS INDICATING NORMAL AND AFTER RUNNING THEIR CHECKLIST THEY WERE CLOSE ENOUGH TO ELP, ATI JET HOME BASE, THEY ELECTED TO DIVERT THERE. THE AIRCRAFT WAS LANDED SAFELY AT ELP. ATI MAINTENANCE ACCESSED THE RH ENGINE DRIVEN HYDRAULIC PUMP AND FOUND THE DRIVE SHAFT HAD BEEN SHEARED. THE ENGINE DRIVEN HYDRAULIC PUMP WAS REPLACED WITH AN OVERHAULED PUMP. THE HYDRAULIC PRESSURE AND RETURN FILTERS WERE REMOVED AND INSPECTED FOR CONTAMINATION. A VERY MINOR AMOUNT OF ULTRA FINE METAL PARTICLES WAS FOUND. THE HYDRAULIC RESERVOIR WAS DRAINED AND INSPECTED WITH VERY LITTLE METAL PARTICLES FOUND IN THE FLUID. THE ENTIRE HYDRAULIC SYSTEM WAS DRAINED AND FLUSHED. NEW FILTERS WERE INSTALLED AND THE HYDRAULIC/AIRCRAFT SYSTEMS WERE CYCLED SEVERAL TIMES. THE FILTERS WERE REMOVED AND RESERVOIR DRAINED FOR INSPECTION - A VERY SMALL AMOUNT OF CONTAMINATION WAS NOTICED IN THE RETURN FILTER AND NONE IN THE RESERVOIR. THE PROCESS WAS REPEATED WITH CLEAN RESULTS, NEW HYDRAULIC FILTERS WERE INSTALLED. THE ENGINE WERE RUN UP INDIVIDUALLY AND NORMAL SYSTEM PRESSURE WAS ACHIEVED. FILTERS WERE THEN REMOVED AGAIN FOR INSPECTION - BOTH FOUND TO BE CLEAN REINSTALLED FILTERS AND LEAK CHECKED - AIRFCRAFT WAS RETURNED TO SERVICE.