Parts to be Inspected

TB 1-1520-240-20-131

Head, Rotary Wing, AFT

145R2004-12

1615-01-298-0763

Head, Rotary Wing, AFT

145R2004-18

1615-01-315-3972

Head, Rotary Wing, AFT

145R2004-20

1615-01-391-4399

Parts to be Inspected .

NOMENCLATURE

PART NUMBER

NATIONAL STOCK NUMBER

Forward Rotor Hub

114R2050-19

N/A

Forward Rotor Hub

114R2050-21

1615-00-004-8891

Forward Rotor Hub

114R2050-39

1615-01-246-1341

Forward Rotor Hub

114R2050-41

1615-01-246-1342

Aft Rotor Hub

114R2050-20

N/A

Aft Rotor Hub

114R2050-22

1615-00-004-8889

Aft Rotor Hub

114R2050-40

1615-01-246-1345

Aft Rotor Hub

114R2050-42

1615-01-246-1346

Inspection Procedures.

NOTE

Only hubs that contain lightening holes in the vertical web areas require

these inspections. Not all rotor hubs contain these lightening holes. See

paragraph 7 for the part numbers of affected rotor hubs.

a. Perform records check and visual inspection of main rotor hubs to determine the part numbers of

hubs installed. If the hub is not affected, the inspection is complete for that aircraft. Clear the DA Form

2408-13-1 entry and report compliance.

Prepare aircraft for safe ground maintenance.

c. Remove the locking beams from the horizontal hinge pin caps in accordance with TM

55--1520--240--23, Task 5--40 (CH--47D), or TM 1--1520--252--23, Task 5--50 (MH--47E).

Completely clean the area around the lightening holes using Acetone 0--4--51 or equivalent.

e. Visually inspect the area surrounding the lightening holes for cracks. Rotor hubs that are found to

have cracks are non--serviceable. If cracks are found proceed to paragraph 9a.

f. If no cracks are found, reinstall the locking beams in accordance with TM 55--1520--240--23, Task

5--41 (CH--47D), or TM 1--1520--252--223, Task 5--52 (MH--47E). Proceed to paragraph 9b for recurring in-

spection.

Correction Procedures.

a. If any cracks are found in the hub, the rotor head assembly must be replaced with a rotor head as-

sembly that is in compliance with this ASAM.

(1) Prepare aircraft for safe ground maintenance.

(2) Remove the rotor head assembly in accordance with TM 55--1520--240--23, Task 5--8

(CH--47D), or TM 1--1520--252--23, Task 5--9 (MH--47E).

(3) Refer to paragraph 10b for requisition instructions for replacement parts.

NOTE

Ensure that the replacement rotor head is in compliance with this ASAM

prior to installation.

(4) Install the replacement rotor head assembly in accordance with TM 55--1520--240--23, Task

5--9, (CH--47D), or TM 1--1520--252--23, Task 5--10 (MH--47E).