TM 1-1510-225-MTF
PROCEDURE
TROUBLESHOOTING
R E F E R E N C E
AVIONICS FLIGHT CHECKS (CONT)
Verify that course deviation bar
is nearly centered and the lo/from
indicator reads to.
(f) Set reciprocal of direction to sta-
tion on course indicator (EHSI)
using remote course knob (pedes-
tal extension). Observe that
course deviation bar is nearly
centered and the to/from indicator
reads from.
(g) Set direction to station again on
course indicator (EHSI) using
remote course knob (pedestal
extension). Observe that course
deviation bar is nearly centered
and the to/from indicator reads
to.
(h)
Fly a 90° right turn such that the
flight path is at a 90° angle to the
direction to the station. Observe
that the course deviation indica-
tor needle deflects noticeably to
the left after one or two miles of
flight (assuming the station is 25
to 50 miles from the aircraft).
(i) TACAN range test - Achieve
adequate usable reception at 45
miles at 1,250 feet above station
antenna altitude.
(j) TACAN ground-track accuracy
test - Fly aircraft over a predeter-
mined ground check point. The
maximum error is ±3%.
(k) TACAN distance measuring
equipment
- Check against
known distances (on the ground
if possible) using known check-
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