(3) Disconnect the linkage assembly fastener from
(3) Set the WPN CONT (or WPN CONTR) selec-
the BIT position, or stow position, and attach it to the
tor switch on the pilot armament control panel (fig. 2-1)
helmet sight assembly receptacle magnet as shown in figure
to GUNNER. Set the MODE SELECT switch on the TOW
control panel (fig. 2-9) to OFF. The gunner presses the
2-13. Close the latch around the fastener by pushing the
ACTION switch on the TSU left hand grip and moves the
mechanism back and down.
helmet sight. The turret follows the gunner's head move-
(4) The gunner makes a rapid rotational head
The linkage must be connected to the helmet
movement with the ACTION switch pressed. The reticle
sight receptacle before the reticle will light or
flashes until the commanded gun line is coincident with the
the gun turret will leave the stow position.
helmet line of sight.
(4) Turn the HSS RTCL OFF BRT (or HSS RTCL
c. Checkout With TSU
OFF BRT) control on the pilot armament control panel
(fig. 2-1) or the HSS RETICLE OFF BRT (HSS RTCL OFF
(1) Set the MODE SELECT switch on the TOW con-
BRT or HSS OFF BRT) control on the gunner armament
trol panel (fig. 2-9) to TSU/GUN (or TSU GUN). Wait for
control panel (fig. 2-2) to BRT (fully clockwise), rotate the
the PWR ON display to appear.
sight into the field of view, and adjust the eyepiece laterally
and vertically until the full reticle, including the outer ring,
can be seen centered in the eyepiece outline. To adjust the
(1) Set the MODE SELECT switch on the TOW
eyepiece vertically (fig. 2-1.4), compress the ends of the
control panel (fig. 2-9) to TSU/GUN. Wait for the PWR ON
spring lock with the left hand and move the eyepiece up or
display to appear.
down with the right hand. To adjust the eyepiece laterally
(2) Hold the ACQ TRK STOW switch on the sight
(fig. 2-15), grasp the sight housing firmly and apply enough
hand control (fig. 2-5) in ACQ.
rotational force to overcome the effect of the friction disk
and cause the housing to rotate.
(3) Move the helmet sight to sight on a target.
(5) Actuatc the HSS RTCL TEST (or HSS RTCL
(4) Release the ACQ TRK STOW switch to TRK.
TEST ) switch on thc pilot armament control panel (fig.
The eyepiece retracts. Look into the TSU and observe that
2-1) or the HSS RETICLE TEST (HSS RTCL TEST or HSS
the same target is in the field of view.
LAMP TEST) switch on the gunner armament control panel
(fig. 2-2). The reticle remains lighted. If the reticle goes out,
(5) The gunner extends his helmet sight eyepiece.
one or more of thc reticle lamps may have failed. For cor-
rective action, refer to paragraph 3-10.
(6) The pilot selects a target with his helmet sight
b. Checkout With Turret.
and identifies the target for the gunner.
(1) Set the WPN CONT (or WPN CONTR) selector
(7) The gunner presses and holds the PHS ACQ
switch on the pilot armament control panel (fig. 2-1) to
pushbutton (fig. 2-5). The gunner eyepiece retracts and the
PLT (or PILOT) The pilot presses the ACTION switch
TSU slews to the pilot's target.
on the cyclic stick grip and moves the helmet sight. The
turret follows the pilot's head movements.
(8) The gunner releases the PHS ACQ pushbutton,
and observes the pilot's target in the TSU field of view.
(9) Set the ACQ TRK STOW switch to STOW, the
MODE SELECT switch to OFF. the MASTER ARM switch
to OFF, the INV (or ALTNR) switch to OFF and the BAT
(or BATTERY) switch to OFF. Disconnect hydraulic
Clear all personnel from gun turret area before
power and electrical power in accordance with TM 55-
1520-234-23 (for the AH-1S(Mod) helicopter), or TM
55-1520-236/239-23 (for the AH-1S
(2) The pilot makes a rapid rotational head
movement with the ACTION switch on the cyclic stick grip
(fig. 2-4) pressed. The reticle flashes until the commanded
gun line is coincident with the helmet line of sight.