Service difficulty report · Pulley · Dhav DHC8102

Difficulty date
October 13, 2009
Submitted
December 1, 2009
Operation
General aviation
Make and model
Dhav DHC8102
Aircraft time
43,205 hours
Engine
Pwa PW120A
Propeller
Hamstd 14SF7
Part
Pulley
Part number
82742339001
Condition
Split
Location
Spoilers
Stage of operation
IN
How discovered
9
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

(CAN) WHILE INSPECTING THE ROLL SPOILER CABLE DISCONNECT MOD SWITCHES (SB 8-27-89), THE PULLEY ON TRIGGER ARM WAS FOUND SPLIT IN HALF LEAVING THE CABLE RIDING THE METAL BEARING. CLOSER INVESTIGATION REVEALED THAT DIAMETER OF THE CABLE APPEARS TOO BIG FOR THE PULLEY TYPE INSTALLED CAUSING THE CABLE TO EXERT SIDE PRESSURE ON THE INNER WALLS OF THE PULLEY. THIS MAY HAVE CAUSED PREMATURE FAILURE OF THE PULLEY. A NEW PULLEY DOES NOT RESOLVE THE CABLE DIAMETER TO PULLEY INNER DIAMETER MISMATCH. ALTHOUGH THE PULLEY WAS REPLACED UNDER WO200277 NR-00512 , ISSUE REMAINS NOTE: THIS INSTALLATION ALSO REFERENCES AD CF2006-13, DATED 12 JULY 2006.