Section V. TROUBLESHOOTING - TM-9-1270-212-14-P0135

TM 9-1270-212-l4&P

Section V. TROUBLESHOOTING

3-9. BIT Test.

Assembly Troubleshooting.

3-10. Helmet Sight

a. Perform the BIT test as follows:

NOTE

(1) Insure that the circuit breakers and switches are

In the procedures below, where the nomencla-

set as specified in paragraph 2-4 for proper helicopter

ture of a control, control position, or indicator

configuration.

differs between the AH-1S(Mod) and the

helicopters, the basic nomen-

(2) Place both the gunner and pilot linkage

clature used is that for the AH-1S(Mod) heli-

assemblies in the BIT position (fig. 2-11).

copter and the nomenclature for the AH-1S

helicopters follows, in parentheses

(3) Actuate the BIT switch on the gunner armament

and prefixed with an "or" for example, "HSS

control panel.

RETICLE TEST (HSS RTCL TEST or HSS

L A M P TEST)" in a(3) b e l o w .

When the failure indication occurs, insure that the

linkages are properly attached to the BIT magnets and

check all cable connections. Then repeat the BIT test as

The troubleshooting consists of a test of the reticle light

follows:

using helicopter power and an electrical eyepiece retraction

test.

(1) Cycle the MASTER ARM switch on the pilot

armament control panel from STBY to OFF and back to

a. Reticle Light Test Using Helicopter Power. Perform

STBY.

the reticle light test using helicopter power as follows:

(2) Actuate the BIT switch on the gunner armament

(1) Insure that the MASTER ARM switch on the -

control panel. If the failure still exists, refer to table 3-4 for

pilot armament control panel is in the STBY position.

the assembly to be replaced.

Table 3-4. BIT Test Troubleshooting Procedures

BIT failure

Corrective action

Probable cause of failure

indication

a. Electronic interface assembly

Replace the EIA (paragraph 3-15).

1. PLT

b. Pilot linkage assembly

Notify DS/GS maintenance personnel.

a. Electronic interface assembly

Replace the EIA (paragraph 3-15).

2. GNR

b. Gunner linkage assembly

Notify DS/GS maintenance personnel.

c. Extension cable

Notify DS/GS maintenance personnel.

Electronic interface assembly

Check connectors, then replace the EIA (paragraph

3. INTFC (or EIA)

3-15).

3-5