Service difficulty report · Piston · Boeing 107*

Difficulty date
July 12, 2010
Submitted
July 16, 2010
Operation
General aviation
Aircraft
N191CH
Make and model
Boeing 107*
Aircraft serial
2003
Aircraft time
37,792 hours
Part
Piston
Part number
A02R27443
Part serial
CH4704
Condition
Broken
Location
Lag Damper
Part time
1,327 hours
Component
Lag Damper · Boeing
Component part number
A02R27001
Stage of operation
HO
How discovered
O
Nature of condition
E
Precautionary procedure
C

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

What was found

CAME TO A HOVER ABOVE THE HOOKER, AT THAT TIME WE FELT A LIGHT TO MODERATE LATERAL SHUFFLE. NO UNUSUAL NOISE. NOT KNOWING WHAT WAS CAUSING THE SHUFFLE, WE CHECKED THE SAS SYS, SINGLE, BOTH AND NO SAS WITH NO CHANGE IN THE SHUFFLE. PILOT APPLIED POWER AND IT GOT SLIGHTLY WORSE AND DECREASED POWER IT REDUCED THE INTENSITY A BIT. THEN DECIDED TO TRY A LITTLE FWD AIR SPEED TO SEE IF IT GOT WORSE. IT DID NOT, SO WE DECIDED TO FLY BACK TO SERVICE TO CHECK IT OUT, APPROX. 1NM. LANDED WITHOUT FURTHER PROBLEMS. ONCE ON THE GROUND, THE MX CHECKED THE EXTERIOR OF THE ACFT THEN CAME INSIDE AND CHECKED THE SAS CLOSET AND FOUND NOTHING VISIBLY WRONG. PILOT SHUT THE ACFT DOWN. DURING COAST DOWN, RPM UNSURE BUT BELOW 40 PERCENT, THERE WAS SEVERAL LOUD BANGS OVERHEAD. AFTER THE BLADES HAD STOPPED WE CHECKED UP TOP FWD, AND FOUND THE FWD RED LAG DAMPER SHAFT BROKEN. AFTER FURTHER INSP. THE MX FOUND THAT THE RED PITCH ARM WAS DAMAGED AND CRACKED. ASLO FOUND DAMMAGE TO THE GREEN PITCH ARM. PROTECTED FROM THE WIND AT SERVICE SO DON'T KNOW IF IT WAS A CONTRIBUTING FACTOR. HAD BEEN FLYING LOGS FOR APPROX 50 MIN AND HAD NOT NOTICED ANYTHING UNUSUAL PRIOR TO THE EVENT.