190-01279-01
GTS 8XX Part 23 AML STC Maintenance Manual
Rev. 2
Page 7-11
7.4.3.1 Alternate Flight Check
A flight check of the GTS 8XX system may be performed in the event a TIC TR220 or other ramp tester is
unavailable. The flight check is performed with the GTS 8XX system test aircraft in addition to a target
aircraft with an operating transponder installed. The purpose of the flight check is to evaluate the
GTS 8XX system installation and confirm traffic is displayed at the correct relative bearing and altitude
and targets are portrayed correctly. It is performed as an
alternative
to the Ramp Test and Return to
Service Test. After takeoff, observe traffic on the display and verify visually the display is accurate
regarding intruder bearing, relative altitude, and range.
CAUTION
The flight check must be performed in Visual Meteorological Conditions (VMC) to allow
visual acquisition of the target aircraft. Maintain constant radio contact with the target
aircraft throughout the flight check to ensure safe separation minimums.
CAUTION
Do not perform head-to-head maneuvers with the target aircraft. For safety, all
maneuvers should be performed in the same direction with GPS using offsets from known
NAV aids so both pilots know the test aircraft to target aircraft separation at all times.
1. With the GTS 8XX system powered up and
“Standby” indicated on the traffic display, cycle
the GTS 8XX system to
Operate
.
NOTE
Each time the GTS 8XX system transitions
between these modes, a self-test of the antenna
circuit is initialized. If the antenna connection is
not correct, the traffic display will display
“Failure” indicating it will be necessary to
recheck the antenna coaxial connections.
2. If the traffic displays “Operate” without
indicating a fault, proceed to the flight test.
3. Ensure the test aircraft and the target aircraft
maintain a 1,000-foot altitude separation.
4. Verify the visual location of the target aircraft
matches the location of the target on the display.
NOTE
For each of the target aircraft scenarios below, the target should appear on the traffic
display as a filled diamond with a
±
10 above, which indicates proximate traffic at 1,000
feet above or below test aircraft altitude. The plus symbol (+) indicates proximate traffic
above test aircraft altitude. The minus symbol (-) indicates proximate traffic below test
aircraft altitude.
Test
Aircraft
Target
Aircraft
4 NM
Figure 7-6 Target Aircraft Position for
Traffic Display Flight Check
