TB 1-1520-238-20-122
e. Component/Parts in Stock at All Levels (Depot and Others) Including War Reserves. N/A.
f.
Components/Parts in Work (Depot Level and Others). N/A.
2.
4.
Summary of the Problem.
a. AH--64--01--08 (TB 1--1520--238--20--120) required an initial torque check of the 4 bolts used to
attach the transmission rotor support strut assemblies to the deck of the aircraft. In addition to other
changes, that SOF also lowered the torque from 3500 inch pounds to 1900 inch pounds and established
a recurring torque check of the bolts. Data gathered from the field has determined a need to change the
recurring inspection procedures.
b. For manpower/downtime and funding impacts, see para 12.
c. The purpose of this TB is to revise the recurring inspection procedures IAW para 8c. All other
procedures IAW AH--64--01--08 (TB 1--1520--238--20--120) remain the same.
5.
End Items To Be Inspected.
All AH--64 series aircraft.
6.
Assembly Components To Be Inspected. Same as AH--64--01--08 (TB 1--1520--238--20--120).
7.
Parts To Be Inspected. Same as AH--64--01--08 (TB 1--1520--238--20--120).
Inspection Procedures.
a. Initial Inspections -- Same as AH--64--01--08 (TB 1--1520--238--20--120).
b. One Time Barrel Nut/Bolt Inspection -- Same as AH--64--01--08 (TB 1--1520--238--20--120).
c.
Recurring Inspection --
(1) Clear the red horizontal dash //--// entry required IAW paragraph 1a of AH--64--01--08.
(2) Perform the following recurring torque check every 20 flight hours/28 days.
NOTE
The recurring torque check is not required if HS4243V12H34/62 or
HS4243--12H34/62 bolts are installed with HS5813--12 barrel nuts.
(3) Remove lockwire from the bolt.
inch pounds, insure bolt does not turn.
(6) If the bolt does not turn, set the torque wrench to 1900 inch pounds, and insure bolt is
torqued to 1900 inch pounds.
(a) Mark head of bolt with torque stripe or white paint stripe to indicate a recurring torque
check is required.
(b) Lockwire the bolt to the strut using the single fastener application, double twist, single
hole method IAW TM 1--1500--204--23--6. This portion of the inspection is complete.
(7) If lockwire is found broken during the recurring torque check, contact the Tech POC in
para 16a immediately.
(8) The recurring torque check is required until the barrel nut and/or bolt are removed and
replaced with a HS5813--12 nut, a redesigned replacement nut for part number 7--311113224 (when
available, new part number TBD) nut and/or bolt HS4243V12H34/62 or HS4243--12H34/62 prior to 2
August 2003 IAW para 9 of this SOF.
2
Previous Page
