BHT-412-MM-2
5-00-00
01 JUN 2018 Rev. 26 Page 151
Export Classification C, ECCN EAR99
5-28. EACH 2500 HOURS OF MAIN ROTOR HUB ASSEMBLY OPERATION
DATA REFERENCE INSPECTION TASK DESCRIPTION
INITIAL
MECH OTHER
DATE: __________________W.O. _____________________
FACILITY: __________________________________________
HELICOPTER S/N: ___________________________________
REGISTRY NO.: _____________________________________
TOTAL TIME:_______________________________________
SIGNATURE:________________________________________
Accomplish each 2500 hours of main rotor hub
operation.
MAIN ROTOR HUB ASSEMBLY (412-010-100-SERIES)
AND 412-010-502-SERIES
Chapter 62
BHT-412-CR&O
1. Disassemble main rotor hub. Visually inspect eight drive
pins 412-010-166.
Pitch horn to spindle attachment bolts do not need to
be removed unless there is evidence of looseness
or external corrosion on the bolt head.
2. Visually inspect yoke flexures, spindles, pitch horns, upper
and lower cone seats, and spline plate for condition. Inspect
and replace (if required) buffer pads on yoke. Inspect yoke
bushings for condition.
TB 412-92-112
Some yoke assemblies 412-010-101-123,
-127 were delivered with oversized bushings.
3. Visually inspect all elastomeric bearings for condition,
deterioration, and separation.