Service difficulty report · Bearing · Cessna 525C

Difficulty date
February 24, 2025
Submitted
March 26, 2025
Operation
General aviation
Aircraft
N423NE
Make and model
Cessna 525C
Aircraft serial
0413
Aircraft time
1,726 hours, 989 cycles
Part
Bearing
Part number
MS21155S16
Condition
Seized
Location
Zone 700
Part time
1,726 hours, 989 cycles
Component
Trunnion · Cessna
Component part number
71410201920
Stage of operation
IN
How discovered
V
Nature of condition
O
Precautionary procedure
K

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

What was found

AIRCRAFT WAS IN MAINTENANCE TO HAVE THE MAIN LANDING GEAR ACTUATORS REPLACED DUE TO REACHING THEIR LIFE LIMIT. DURING THIS MAINTENANCE IT WAS NOTED THAT BOTH MAIN LANDING GEAR FORWARD TRUNNION PIVOT BEARINGS WERE SEIZED WHICH CAUSED RESISTANCE/BINDING WHEN RETRACTING AND EXTENDING THE MAIN LANDING GEAR DURING GEAR FUNCTIONAL CHECKS. MAINTENANCE CREWS ATTEMPTED TO GREASE THESE TWO FORWARD TRUNNION BEARINGS, HOWEVER THEY WOULD NOT EXCEPT ANY GREASE. DURNING REMOVAL OF BOTH MAIN LANDING GEAR TRUNNIONS TO GAIN ACCESS FOR THE INSPECTION OF THESE BEARINGS IT WAS NOTED THAT THE BEARINGS HAD SEIZED INTERNALLY AND WERE SEIZED TO THE FORWARD TRUNNION PIVOT PINS. THE BEARINGS BEING SEIZED TO THE TRUNNION PIVOT PINS CAUSED THE TRUNNION PIVOT PIN LOCKING BOLTS TO SHEAR ON BOTH (LEFT & RIGHT) MAIN LANDING GEAR TRUNNIONS. BOTH MAIN LANDING GEAR TRUNNIONS, BOTH TRUNNION FORWARD PIVOT BEARINGS, BOTH PIVOT PINS REQUIRED REPLACEMENT. NOTE: LUBRICATION INTERVAL PER THE TEXTRON AVIATION 525C MM FOR THIS BEARING IS ONCE EVERY 12 MONTHS.

More about the Cessna 525C