BHT-412-MM-2
5-00-00
01 JUN 2018 Rev. 26 Page 159
Export Classification C, ECCN EAR99
5-31. EACH 2500 HOURS OF TAIL ROTOR DRIVE SYSTEM 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 tail rotor drive
system operation on helicopters S/N 36020 through
36999, S/N 37002 through 37999, S/N 38001
through 38999, S/N 39101 through 39999, and
helicopters modified by 412-570-001-103 or Post
BHT-412-SI-74 (412SP to 412HP Upgrade).
Chapter 65 TAIL ROTOR DRIVESHAFT
1. Check torque of nuts at laminated disc couplings by applying
torque. Do not exceed 280 inch-pounds (31.64 Nm). If nut rotates
under torque, inspect attachment hardware, driveshafts, disc
packs, couplings, and adapters, as applicable, for serviceability.
Replace as required.
2. Visually examine laminated disc assemblies for separation,
deflection, distortion, cracks, missing sections, and correct
installation of bolts and washers.