TB 1-1520-240-20-148
in all condition codes listed in paragraph 6 are annotated to read: "CH-47-02-06 (TB 1-1520-240-20-148) in-
spection of combining transmission not complied with."
(1) Wholesale Stock -- Upon receipt of this message, depot and material activity commanders
will ensure all items in condition codes //A//, //B//,//C//, //D//, and //E//, listed in paragraph 6, are placed in
condition code //J// and tagged with a suspended tag/label - material, DD Form 1575/DD Form 1575-1. Do
not remove original condition tags.
(2) Retail Stock -- Report receipt of this message in accordance with paragraph 14c(1) no later
than 21 June 2002. Upon receipt of this message , commanders and facility managers maintaining retail stock
at installation level and below shall contact the supported aviation unit to perform the procedures required
in accordance with paragraphs 8 and 9 on suspect materiel. Dispose of discrepant materiel in accordance
June 2002
f. Components/Parts in Work (depot level and others) - depot and other maintenance activity com-
manders will ensure items listed in paragraph 6 are not issued until they are in compliance with this message.
2. Task/Inspection Suspense Date. Complete the inspection in
accordance with paragraph 8 prior to
next
engine start but no later than 25 June 2002 and report in accordance with paragraph 14A(2) no later than 28
June 2002.
3. TAMMS Reporting Compliance Suspense Date.
Report compliance in
accordance with paragraph
14a(1) no later than 25 June 2002.
4.
Summary of the Problem.
a. A unit reported that after experiencing a debris screen latch, they found plastic type debris in the
combining transmission oil filter. Analysis of the debris revealed that it was plastic media. It has been deter-
mined that this material is the result of the use of plastic media blast procedure by CCAD to remove surface
coatings from the housing assemblies. This procedure can leave particles inside the transmission that could
interfere with necessary oil flow.
c.
The purpose of this Technical Bulletin is to:
(1) Conduct records check and visual inspection of all combining transmissions.
(2) Remove specific serial numbered combining transmissions from service
(3) Inspect combining transmissions overhauled at CCAD between 28 June 2000 through 17
June 2002 for presence of plastic media blast particles.
5.
End Items to be inspected. CH-47D/CH-47F/MH-47D aircraft.
Assembly Components to be Inspected.
PART NUMBER
NATIONAL STOCK NUMBER
NOMENCLATURE
Combining Transmission Assy
145D5300-ALL
ALL
7.
Parts to be Inspected.
PART NUMBER
NATIONAL STOCK NUMBER
NOMENCLATURE
Element, Filter, Fluid
145DS023-6
Element, Filter, Fluid
145DS514-4
Element, Filter, Fluid
145DS514-7
Filter, Assembly
145DS523-2
4330-01-114-0918
2