Jammed, Cracked, Loose

The following information is derived from the FAA’s Service Difficulty Reports and Aviation Maintenance Alerts.


Beech Model 76 Duchess Corroded Elevator Spar
Left and right elevators were disassembled for repair. When the inboard flange was removed, exfoliating corrosion was found on spar. Corrosion is located under flange attach to spar and is not visible until parts are disassembled. The submitter suggests the issue isn’t one of flight time but the calender.
Part Total Time: 5032 hours


Cessna Model 172N Skyhawk Failed Circuit Breaker
Pilot noted a clicking sound accompanied by ammeter indicating a heavy discharge. Problem isolated to a circuit breaker that wasn’t tripping the indicator button and was working as an auto-reset breaker. A short was located within the “inop” ADF. The owner commented he thought the issue was normal for the pulse-light system.
Part Total Time: Unknown

Cessna Model 177RG Cardinal RG Cracked Main Wheel Hub
Left brake reported as soft, requiring repeated applications to engage. Inspection revealed a large crack on the inside of the wheel hub. Cracks also were discovered in the area of four of the six mounting bolts, parallel to the bolt hole centerline axis and approximately one-inch long. The right wheel was disassembled and cracks were found parallel to the centerline of two mounting bolts.
Part Total Time: 4655 hours

Continental IO-520-BB Loose Alternator Drive Gear
During oil change, steel and red rubbery debris were found in filter. Removed alternator and discovered metal coming from driving gear on crankshaft and alternator driven gear, and rubber coming from alternator drive coupler. Four bolts holding crankshaft gear to crank were loose, allowing gear to slop around and cause wear of gears and coupler. Locking plates securing the four bolts were missing.
Part Total Time: 2170 hours

Champion RHB32S Spark Plugs Cracked Insulators
Engine start of the IO-550-N in a Cirrus SR22 was normal. Magneto check on run-up revealed rough-running and failed spark plugs on several cylinders. Removed the plugs and cracks found all around the insulators. Have been finding several of these on multiple aircraft. The issue is isolated to the brand.
Part Total Time: 300 hours

Mooney Model M20J 201 Jammed Elevator
Elevator jammed in full nose-up position during pre-flight inspection. Pushing the yoke toward the instrument panel was not possible. Investigation narrowed the problem down to the left bungee trim assist assembly (p/n 740188-000), which was jammed.
Part Total Time: 1680 hours


Please enter your comment!
Please enter your name here