TB 1-1520-238-20-114
5.
End Items To Be Inspected .
All AH-64 aircraft.
6.
Assembly Components To Be Inspected.
NOMENCLATURE
PART NUMBER
NSN
Main Transmission
7-311310001-All
All
7.
Parts To Be Inspected .
NOMENCLATURE
PART NUMBER
NSN
Clutch Assembly
7-311310003-9
Clutch Assembly
7-311310003-7
8. Inspection Procedures. Inspect the main transmission input clutch to determine the part number of
the input clutch assembly installed.
a.
If clutch assembly P/N 7-311310003-9 is installed, inspection is complete.
b.
If clutch assembly P/N 7-311310003-7 or an earlier configuration is installed, proceed to paragraph 9.
9.
Correction Procedures.
a. Determine the time since last overhaul. If the clutch assembly has never been overhauled,
determine the Time Since New (TSN).
(1) If it is determined that the time since overhaul or TSN is in excess of 500 hours, the clutch
is unserviceable. Replace the P/N 7-31130003-7 or earlier configuration clutch assembly with a P/N
7-311310003-9 assembly.
NOTE
The input clutch assembly P/N 7-311310003-9 will retain the
original TBO of 2500 hours.
(2) If the time since overhaul or TSN is less than 500 hours, change the main transmission
assembly DA Form 2408-16 entry for TBO on P/N 7-311310003-7 and earlier clutch assemblies to reflect the
new 500 hour TBO. Recalculate the replacement due time.
(3) ULSS-A units will use this TB as authority to change the legitimate code file to reflect the new
TBO. Contact the ULSS-A Point of Contact in paragraph 16.e. if you have questions regarding ULSS-A
changes.
b. If the time since overhaul or TSN is more than 500 hours, return the P/N 7-311310003-7 and earlier
clutch assemblies to depot for upgrade to a P/N 7-311310003-9 configuration.
This TB supersedes USAAMCOM Aviation Safety Message 141240Z Dec 00 (AH-64-ASAM-01-04).
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