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TCAS COCKPIT TEST PROCEDURES
TCAS should be tested using the pilot
initiated self test feature during cockpit
preparation.
After passing self test, TCAS shouldremain in SBY before
takeoff.
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TCAS self test determines the
operational status of the entire TCAS system.
Select self test on the TCAS control panel.
Once begun, self test continues automatically for
approximately eight seconds.
During self test, normal TCAS operation is inhibited.
During the first few seconds of the test sequence, the
traffic display allows verification of each type of Intruder
symbol. The test generates the symbols arranged as shown.
The traffic display annunciates the word TEST.
TCAS SELF TEST
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SYMBOLS
OTHER TRAFFIC - hollow cyan diamond.
Indicates other traffic, (the predicted flight paths do not
penetrate the Collision Area) which
are within range of the display.
PROXIMATE TRAFFIC - solid cyan diamond.
Indicates other traffic within 6 NM and within +/- 1200 ft
vertically. Proximity traffic are
shown to improve situation awareness.
TRAFFIC ADVISORY - solid amber circle.
Indicates intruder aircraft predicted to enter the Collision
Area within 35-45 seconds.
RESOLUTION ADVISORY - solid red square.
Indicates intruder aircraft predicted to enter the Collision
Area within 20-35 seconds.
PLUS or MINUS
the amber -03 and "arrow up" indicates an aircraft 300 feet
below and climbing with a rate of
more than 500 fpm.
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The same instrument during TCAS test.
RED ARC.
Restricted vertical speed. This area instructs the pilot
whatvertical speed regions is to be avoided during an RA.
GREEN ARC.
FLY-TO vertical speed arc. This area instructs the pilot of
thevertical speed to ensure safe altitude separation
fromconflicting traffic. TCAS expects adjustment in pitch
attitudeto attain the desired vertical rate within 5 seconds
during
an RA.
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At the end of test sequence an aural
message "TCAS System Test Okay"or "TCAS System Test Fail" will
beannunciated. If the FAIL light stayson, it denotes a failure in
the transponder orunits monitored by the transponder.
FAIL illuminates for 1second to verify operation of the light
and testmode in the transponder.Transponder code digits will
display 8888 for 1second to verify that all digit segments will
illuminate.
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TCAS Limitations
TCAS is limited to supporting only vertical
separation advisories.
TCAS is not fitted to many smaller aircraftmainly due to the
high costs.
ATC can be automatically informed about
resolution advisories issued by TCAS only
when the aircraft is within an area covered
by a Mode S.
