Summary of the Problem. - TB-1-1520-240-20-1310002

TB 1-1520-240-20-131

(1) Surface/Air Shipment. Within 10 flight hours or 14 days of arrival.

(2) Ferry Status.

(a) Inspect at final destination within 10 flight hours or 14 days of arrival.

(b) Boeing will inspect DD250 aircraft prior to those aircraft departing for ferry to final destina-

tion.

Maintenance Trainers (Category A and B). Comply no later than 8 March 2001.

f. Component/Parts in Stock at All Levels (Depot and Others). Including War Reserves -- Upon receipt

of this message, Depot and Materiel Activity Commanders will ensure the materiel condition tags of all items

in all condition codes listed in paragraphs 6 and 7 are annotated to read: "CH--47--01--ASAM--03, (TB

1--1520--240--20--131), rotor hub lightening hole inspections not complied with."

g. Components/Parts in Work (Depot Level and Others). Depot and other Maintenance Activity Com-

manders will ensure items listed in paragraphs 6 and 7 are not issued until they are in compliance with this

message.

2. Task/Inspection Suspense Date. Complete the inspection in accordance with paragraph 8 within the

next 10 flight hours but no later than 23 NOV 00 and report in accordance with paragraph 14b.

3. Reporting Compliance Suspense Date. Report compliance in accordance with paragraph 14a no later

than 5 DEC 00.

Summary of the Problem.

a. A category I deficiency report was received which revealed cracks extending from the lightening

holes in the vertical web area of the rotor head center hub. When discovered, these cracks were greater than

one inch in length. Further investigation revealed the cracks went undiscovered during several phased main-

tenance visual inspections. Research revealed three other rotor hubs that have been found with similaar

cracks.

For manpower/downtime and funding impacts see paragraph 12.

c. The purpose of this Technical Bulletin is to require an initial visual, recurring visual, and recurring

eddy current inspection of the vertical web lightening hole areas of all rotor hubs identified in paragraph 7 of

this message.

End Items to be inspected . All H--47 series aircraft.

Assembly Components to be Inspected.

NOMENCLATURE

PART NUMBER

NATIONAL STOCK NUMBER

Head, Rotary Wing, Forward

145R2003-1

1615-01-118-5634

Head, Rotary Wing, Forward

145R2003-3

1615-01-198-7555

Head, Rotary Wing, Forward

145R2003-4

1615-01-184-3875

Head, Rotary Wing, Forward

145R2003-5

1615-01-345-0477

Head, Rotary Wing, Forward

145R2003-6

1615-01-296-9503

Head, Rotary Wing, Forward

145R2003-9

1615-01-314-8863

Head, Rotary Wing, Forward

145R2003-10

1615-01-391-4398

Head, Rotary Wing, AFT

145R2004-2

1615-01-115-3607

Head, Rotary Wing, AFT

145R2004-6

1615-01-199-1814

Head, Rotary Wing, AFT

145R2004-8

1615-01-184-3874

Head, Rotary Wing, AFT

145R2004-10

1615-01-312-6833