Change 24 16-193
16-5.3 AN/ALE-47 COUNTERMEASURES DISPENSER SYSTEM OPERATIONAL CHECK (Continued)
Do not install CDTs into Countermeasures
Dispenser System (CMDS) dispenser
assemblies before performing CDT BIT check.
1. Set CDT MODE switch (18) to FIRE TEST.
BIT begins automatically. The following displays appear on
All CDT indicators illuminate briefly.
BIT is displayed on upper display field.
S- and software version number is displayed
If no fault is detected PASS message is displayed.
If fault is detected FAIL message is displayed, set MODE
switch to OFF and replace CDT.
2. Set CDT DATA switch (19) to COUNT or
DUAL COUNT (chaff use).
3. Check CDT display (20) for battery message.
If LOW BAT is displayed, refer to TM 341003 (Operation and
Maintenance Technical Manual) accompanying CDTs.
4. Set CDT MODE switch (18) to OFF.
If erroneous expendable counts are displayed,
fastening knobs may require additional tightening.
5. Install CDTs (16) into flare dispenser assemblies
(15) being tested; secure CDTs (16) by tightening
two fastening knobs (17).
6. Apply electrical power to aircraft.
Proceed with AN/ALE-47 CMDS operational
checkout while AN/ALQ-156 MWS is warming
7. Set AN/ALQ-156 POWER switch (10) to ON; press
After 10 minutes, STBY light on AN/ALQ-156 illuminates.
AN/ALQ-156 PUSH FOR STANDBY switch (9) to
initiate standby mode.
8. Set CDT MODE switch (18) to S.V. (stray voltage).
9. Press CDT RESET TEST switch (21).
DC followed by AC is displayed on CDT display (20) for 4
seconds. If stray voltage is not detected, PASS is displayed.
If FAIL message is displayed, failed pin numbers will then be
displayed. Record failed pin numbers. This is an indication that
stray voltage was detected on the dispenser breechplate
terminals. This condition must be corrected before proceeding
with the operational check. Power down the AN/ALQ-156
MWS and remove power from aircraft. Starting at the
dispenser pins, use multimeter to locate the source of stray
voltage. If CMDS is not the source of the stray voltage, the
aircraft wiring must be checked to locate and repair the stray
10. Set CDT MODE switch (18) to OFF.
Do not perform operational checkout
of CMDS with payload modules installed
in dispenser assemblies. System could
inadvertently dispense flares resulting
in damage to aircraft or injury or death
11. Ensure DCALE47DCDU (12), NO. 1 SEQ (14),
If DCALE47 DCDU circuit breaker is open, close it. If it does
and NO. 2 SEQ (13) circuit breakers on EAPS
not stay closed, go to Task 16-5.4.
1 PDP (11) are closed (in).
12. Adjust DCDU (4) and Misc. Control panel (3) edge
DCDU and misc. control panel edge brightness goes
lighting from dim to bright and set as desired
from dim to bright as control is rotated.
using LTG CTR CSL switch (1) on cockpit
overhead instrument panel.
13. Set the following switches on DCDU (4):
JETTISON switch (8) OFF (switch guard closed)
MANUAL switch (6) 1
14. Set CDT MODE switch (18) to FIRE TEST.
15. Set CDT DATA switch (19) to COUNT.
a. All CDT indicators illuminate briefly.
b. BIT is displayed on upper display field.
c. S- and version number is displayed on CDT.
d. BIT begins automatically.
e. BIT FAIL message is displayed, press RESET TEST
button (21) on CDT; FIRE and 00 messages are
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