Service difficulty report · Jackshaft · Bolkms BK117A1

Difficulty date
September 1, 2000
Submitted
September 18, 2000
Operation
General aviation
Aircraft
N117LF
Make and model
Bolkms BK117A1
Aircraft serial
7013
Part
Jackshaft
Part number
1174120101
Part serial
574
Condition
Corroded
Location
M/R Controls
Part time
7,928 hours
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

DURING INSPECTION, FOUND MASSIVE AMOUNTS OF CORROSION INSIDE CYCLIC JACKSHAFT. SAME LOCATION AS FOUND AND REPORTED PREVIOUSLY ON ANOTHER AIRCRAFT 12-8-99. MANUFACTURER ALLOWS .4 MM ALMOST IMPOSSIBLE TO MEASURE. IT APPEARS LITTLE OR NO PAINT TREATMENT ON INTERIOR OF STEEL TUBE. THE TUBE HAS CASTINGS ON EACH END ANGLED UP AT 45 DEGREES WHICH INCREASES CHANCE OF GETTING FLUIDS INSIDE. THERE ARE NO PROVISIONS FOR DRAINAGE. SUBMITTER SUGGESTED MFG TREAT INTERIOR AND PROVIDE DRAINAGE. THE LAST TIME THIS OCCURRED IT TOOK 3 MONTHS FOR THIS FLIGHT CRITICAL PART OF AN AIRCRAFT STILL IN PRODUCTION TO BE DELIVERED. (X)