TB 1-1520-238-20-114
b. Aircraft in Depot Maintenance. Depot commanders will not issue aircraft until they are in compliance
with this TB.
c. Aircraft Undergoing Maintenance. Commanders and facility managers will not issue aircraft until
they are in compliance with this TB.
d.
Aircraft in Transit.
(1) Surface/Air Shipment. Same as paragraph 1.a.
(2) Ferry Status.
(a) Same as paragraph 1.a.
(b) Boeing will inspect DD 250 aircraft prior to the departure of those aircraft for ferry to final
destination.
e.
Maintenance Trainers (Categories A and B). Same as paragraph 1.a.
f. Components/Parts in Stock at All Levels (Depot Level and Others), Including War Reserves. Upon
receipt of this TB, depot and materiel activity commanders will ensure that the materiel condition tags of all
items in all condition codes listed in paragraphs 6 and 7 are annotated to read as follows: "TB
1-1520-238-20-114, Inspection of the Main Transmission Input Clutch, not complied with."
(1) Wholesale Stock. Upon receipt of this TB, depot and materiel activity commanders will en-
sure that all serviceable items (condition codes //A//, //B//, //C//, //D//, and //E//) listed in paragraphs 6 and
7 are placed in condition code //J// and tagged with a suspended tag/label----Materiel, DD Form 1575/DD Form
1575-1. Do not remove original condition tags. Report compliance with this message in accordance with
paragraph 14.d.(1).
(2) Retail Stock. Upon receipt of this TB, commanders and facility managers maintaining retail
stock at installation level and below shall contact the supported aviation unit to perform the procedures re-
quired in accordance with paragraph 8 and paragraph 9 on suspect materiel. Dispose of discrepant materiel
in accordance with paragraph 10. Report compliance with this message in accordance with paragraph
g. Components/Parts in Work (Depot Level and Others). Depot and other maintenance activity com-
manders will ensure that items listed in paragraphs 6 and 7 are not issued until they are in compliance with
this message.
the next flight and report in accordance with paragraph 14.b.
3.
4.
Summary of the Problem.
a. A recent AH-64 tail rotor drive shaft failure was caused by failure of a main transmission input clutch
P/N 7-311310003-7. The input clutch had 583 flight hours at the time of failure.
b.
For manpower/downtime and funding impacts, see paragraph 12.
c.
The purpose of this TB is to inspect aircraft to accomplish the following:
(1) Determine the part number of the input clutch.
(2) Direct a reduction in Time Between Overhaul (TBO) for the P/N 7-311310003-7 and earlier
configuration clutch assemblies from 1000 hours to 500 hours.
(3) Direct that all P/N 7-31131000-7 and earlier configuration clutch assemblies with more than
500 hours be upgraded to the P/N 7-311310003-9 clutch assembly when returned to depot.
2
