TB 1-1520-238-20-120
NOTE
For aircraft S/N 82--23355 to 84--24311, all 4 bolts will be HS4243V12H34.
For all other aircraft, use only bolt part number HS4243V12H62 for
HS4243--12H34/62 for FS 176 and bolt part number HS4243V12H34 for FS
230.
6. If the part number of the barrel nut is not HS5813--12 series and/or the bolt is
not HS4243V12H34/62 or HS4243--12H34/62, or if a part number cannot be identified, a recurring
torque check is required IAW paragraph 8C until the barrel nut and/or bolt are removed and
replaced with a HS5813--12 nut, a redesigned 7--311113224 (when available), nut and/or bolt
HS4243V12H34/62 or HS4243--12H34/62.
NOTE
Mixing steel and Incontel hardware should be avoided due to the possibility
of corrosion. However, until replacement hardware is available, steel and
Incontel hardware can be used if anti--seize compund is applied to the nut
threads and the torque is reduced to 1900 in lb.
c.
Recurring Inspection --
(1) Clear the red horizontal dash //--// entry required IAW paragraph 1A of AH--64--01--07.
(2) Perform the following recurring torque checks --
(a) The following recurring torque check will be completed every 10 flight hours/14 days until
the visual inspection IAW para 8B has been completed.
(b) Following completion of the visual inspection IAW para 8B, the recurring torque check
will be completed 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.
(4) Using an appropriate mast support wrench per para 11 and torque wrench set at 1900
inch pounds, insure bolt holds torque.
(5) If the bolt turns freely and does not hold torque, replace nut and bolt IAW para 9 and
(6) If the bolt turns slightly, but stops and holds the 1900 inch pounds of torque --
(a) Enter a red horizontal dash //--// status symbol on the DA Form 2408--13--1 with the
following statement; "(Enter bolt location here) bolt turned and requires recheck at next recurring torque
check IAW AH--64--01--08 (TB1--1520--238--20--120)." Ensure you annotate which bolt turned as either
left or right front, or left or right aft.
(b) Mark head of bolt with torque stripe to indicate a recurring torque check is required.
(c) 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.
(d) If bolt turns at the next recurring torque check, replace bolt and nut IAW para 9A and
(e) If bolt does not turn after second check, the red horizontal dash will be cleared. Mark head
of bolt with torque stripe to indicate a recurring check is required. Lockwire the bolt to the strut using the
single fastener appliccation, double twist, sinlgle hole method IAW TM 1--1500--204--23--6 and continue
the recurring check as required.
5