Textron Bell 412 - 5-17. EACH 25 HOURS FOR THE NEXT FOUR INSPECTIONS; TAIL ROTOR HANGER BEARINGS WITNESS MARKS

BHT-412-MM-2
5-00-00
Export Classification C, ECCN EAR99
SPECIAL INSPECTIONS
5-17. EACH 25 HOURS FOR THE NEXT FOUR INSPECTIONS
DATA REFERENCE INSPECTION TASK DESCRIPTION
INITIAL
MECH OTHER
DATE: __________________W.O. _____________________
FACILITY: __________________________________________
HELICOPTER S/N: ___________________________________
REGISTRY NO.: _____________________________________
TOTAL TIME:_______________________________________
SIGNATURE:________________________________________
NOTE
Accomplish visual inspection of witness marks (only
applicable to hanger bearing 204-040-623-003)
each 25 flight hours for the next four inspections
after installation or initial inspection of hanger
bearings.
TAIL ROTOR HANGER BEARINGS WITNESS MARKS
ASB 412-95-84
Revision C
1. Perform helicopter run-up for 5 minutes. Shut down
helicopter and inspect tail rotor hanger bearings for movement
of the dust shields, identified by breakage of the witness marks.
Remove any bearings from service that display dust shield
movement.
2. Hanger bearings not displaying movement at the run-up
may remain in service, but must be inspected for dust shield
movement at each of the next four mandatory 25 hour
inspections, or any time the bearing is inspected between any
of the 25 hour inspections. Bearings that do not display grease
shield movement after the fourth 25 hour inspection may
remain in service with no further inspection required. Record
accomplishment of inspection in the helicopter log book.
3. Remove any hanger bearing from service whose witness
marks indicates that grease shield has moved.
26 FEB 2013 Rev. 16 Page 117/118