TB 1-1520-238-20-139
7.8.1. Left Wing and Pylon - 5. Inspect wing upper mounting flange area and mounting bolts for security,
cracks and corrosion. Upper Wing mount fittings for cracks or distortion. If damage is suspected on mount
fitting, remove wing and perform NDI. Lower Wing mount fittings for cracks or distortion. Mounting bolts for
security, cracks and corrosion. If damage is suspected on mount fitting, remove wing and perform NDI. Pylon
wiring harnesses for security, chafing, and loose connections. Hydraulic and fuel lines for security, chafing,
and leakage.
7.8.2. Right Wing and Pylon - 6. Inspect wing upper mounting flange area and mounting bolts for security,
cracks and corrosion. Upper Wing mount fittings for cracks or distortion. If damage is suspected on mount
fitting, remove wing and perform NDI. Lower Wing mount fittings for cracks or distortion. Mounting bolts for
security, cracks and corrosion. If damage is suspected on mount fitting, remove wing and perform NDI. Pylon
wiring harnesses for security, chafing, and loose connections. Hydraulic and fuel lines for security, chafing,
and leakage.
7.9. Add 250 Hour Hydraulic Oil Inspection and Service.
7.9.1. Aft Equipment Bay - 11. Utility hydraulic manifold for leakage, corrosion, loose connections, and
security. Sight gage for proper fluid level. Check manifold air inlet check valve filter for cleanliness. Replace
Utility hydraulic manifold pressure and return filters. Vent utility accumulator hydraulic pressure by activating
emergency hydraulic system and operating flight controls and verify Utility accumulator NITROGEN pres-
sure.
7.9.2. Main Transmission - 9. Primary hydraulic manifold for leakage, corrosion, loose connections, and
security. Sight gage for proper fluid level. Check manifold air inlet check valve filter for cleanliness. Replace
Primary hydraulic manifold pressure and return filters. Access L200.
7.10. Add 250 Hour Lube Oil Inspection and Service.
7.10.1. Main Transmission - 9. Replace accessory pump oil filter. Remove and clean bypass screen. Access
T250L, T290L, T250R, T290R, L325, R200. Change transmission lube oil and filters. Access L200, R200.
7.10.2. Left Engine and Nose Gearbox - 7. Change nose gearbox lube oil and filter.
7.10.3. Right Engine and Nose Gearbox - 8. Change nose gearbox lube oil and filter.
7.11. Add 250 Hour APU Inspection.
7.11.1. Aft Equipment Bay - 11. Remove APU and inspect the APU mounting hardware, mounts and
mounting lugs' surfaces for cracks, dents, distortion, elongation and corrosion. APU for cracks in compressor
inlet shroud, turbine plenum, or gearbox housing. APU starter for cracks, leakage, and security. APU
combustor for cracks or burned-through areas. Change APU fuel filter.
7.11.2. Aft Equipment Bay - 11. Perform an APU Butt--Weld mounts (PN 7--311651018 for the Tripod Right
mount and 7--311651015 for the Bipod Left mount) Fluorescent Penetrant inspection IAW TM
1--1520--264--23 every 250 hours until replaced with the fish mouth weld mounts. Inspect the welds, the area
around the welds, and the top 3 inches of each mount. No cracks allowed
7.12. Add 250 Hour Main and Tail Rotor Drive Inspection.
7.12.1. Main Transmission -9. Mast base for cracks, distortion, and security. Mast support mount and upper
ends of support struts for looseness. Inspect the upper portion of mast base support in the areas around the
four lightening holes, mast and mixer supports for corrosion and pitting. Access L200, R200.
7.12.2. Main Transmission - 9. Static mast attaching hardware for proper torque. (Use PLI washer method).
(500 Hour for Inconnel/250 Hour for H-11 hardware.)
7.12.2.1. Main Transmission -- 9. Torque check upper case nuts.
7.12.3. Empennage, Tail Rotor, and TLG - 14. Tail rotor and intermediate gearbox mounting NUTS for proper
torque. Access L530, L540, L510, and R510.
7.13. Add 250 Hour Fuel System Inspection.
7.13.1. Mid and Lower Fuselage -- 12. Ammo bay interior fuel cell stress panels for cracks, delamination,
distortion, loose or missing fasteners. Ammo bay interior fuel and hydraulic lines, hoses, fuel vent and drain
tubes for leakage, chafing, corrosion, and security. Refueling line coupling assemblies for torque stripe and
evidence of slippage or leakage. Nitrogen inert components for mounting security, loose or missing hard-
ware, failure of tubes or hoses, and distorted or fractured breakaway valves. Inspect filter drain for obstruc-
tions.
6
