Service difficulty report · Screw · Swrngn SA227AC

Difficulty date
June 19, 2008
Submitted
July 22, 2008
Operation
Air carrier
Aircraft
N26932
Make and model
Swrngn SA227AC
Aircraft serial
AC660
Engine
Garrtt TPE33111U
Part
Screw
Part number
NAS13513H16
Condition
Misinstalled
Location
Ppc Shaft
Component
Ppc Shaft
Component part number
27610181
Stage of operation
CR
How discovered
O
Nature of condition
W
Precautionary procedure
O

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

What was found

IN FLIGHT, THE PPC INPUT LEVER TO THE PPC SHAFT CAME OFF AND PREVENTED THE CREW FROM BEING ABLE TO RETARD THE POWER TO THE LT ENGINE. THIS FORCED THEM TO DO AN INFLIGHT SHUTDOWN OF THAT ENGINE. THE INVESTIGATION FOUND THAT THE SCREW AND SPACER THAT SECURES THE ARM TO THE SHAFT WAS NOT INSTALLED. FURTHER INVESTIGATION SHOWED A DISCREPANCY BETWEEN THE MM AND THE IPC MANUAL FOR INSTALLING THESE PARTS IAW TO AC SN. THE OLDER SN AC (BELOW AC664) ARE NOT INSTRUCTED TO INSTALL THEM (71-00-15 (5) (D). ALSO, THE IPC CONTRADICTS ITSELF 76-10-40, FIG 7 CALLS FOR THE INSTALLATION OF THESE PARTS FOR SN 420-683 HOWEVER 76-10-50 LIMITS INSTALLATION OF THESE PARTS TO SN 664-683. (K)