Service difficulty report · Bearing Race · Robsin R44RAVENII

Difficulty date
July 17, 2006
Submitted
December 4, 2006
Operation
General aviation
Make and model
Robsin R44RAVENII
Engine
Lyc IO540AE1A5
Part
Bearing Race
Part number
C0411
Condition
Rough
Location
Tail Rotor
Part time
36 hours
Component
Drive Assy · Robsin
Component part number
D2242
Stage of operation
NR
How discovered
9
Nature of condition
O
Precautionary procedure
O

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

What was found

(CAN) IT WAS NOTICED THAT THE DAMPER BEARING HAD TURNED ON THE TAIL ROTOR DRIVE SHAFT. SLIPPAGE MARKS WERE ABOUT .5 INCH APART. THE BEARING WAS REMOVED SO IT COULD BE INSPECTED, AND POSSIBLY REINSTALLED. THE BEARING WAS FOUND TO BE ROUGH. IT WAS ALSO NOTED THAT THE GREASE IN THE BEARING WAS A DIFFERENT COLOR THAN THE GREASE IN THE SAME BEARING IN OTHER AIRCRAFT, AND PARTS IN STORES. THE BONDED PLATES WERE THE BEARING SITS WERE MEASURED AND FOUND TO HAVE A TOTAL INDICATED RUNOUT OF .0045 INCH. MANUFACTURES LIMIT IS .003 INCH. THE TAIL ROTOR DRIVE SHAFT ASSEMBLY IS TO BE REPLACED WITH A NEW UNIT. (TC NR 20060718003)