Transponder/Tcas Tuning; Tcas - BOMBARDIER LEARJET 40 Pilot's Manual

Pilot's Manual

TRANSPONDER/TCAS TUNING

Transponder operation is similar to COM and NAV operation in that
depressing a line select key beside the function desired will move the
cursor to that location. Those aircraft without TCAS installed will have
an ATC legend at the top of the transponder window, and those
equipped with TCAS will have ATC/TCAS labeled above the window.
Either transponder 1 or 2 can be selected for use and controlled by
either RMU. A number 1 or 2 will appear in front of the transponder
mode in the ATC window on both RMUs indicating which transponder
has been selected. Transponder side selection is toggled by depressing
the 1/2 key on either RMU with the cursor anywhere within the ATC
window.
The transponder is switched from standby to an operating mode by de-
pressing the line select key adjacent to the mode line. Once the cursor
has been selected, the mode line select key acts as a toggle to switch the
transponder between the standby mode and the active mode. Once the
transponder is in the ALT ON mode, the mode of operation is changed
using the tuning knobs. The active mode of operation can now be
changed by rotating the concentric tuning knobs. Depressing the ID
button of the RMU will initiate an approximate 18 second IDENT mode
on the transponder. This will also illuminate an ID annunciation along
the top edge of the transponder window. A reply annunciator is located
in the upper right corner of the ATC window.

TCAS

The Traffic Alert and Collision Avoidance System (TCAS) provides the
crew with aural and visual indications of potentially dangerous flight
paths relative to other aircraft in the vicinity. The system uses the tran-
sponder to interrogate other transponder-equipped aircraft and deter-
mine their bearing, range, and altitude, if the intruder has an altitude
encoding transponder in operation. Advisories are issued to the crew
via the airplane Primary Flight Displays (PFDs), audio system and
Multi-Function Displays (MFDs) (traffic map). Two levels of TCAS are
in use today, TCAS I and TCAS II. TCAS II, the standard on the Learjet
40, is the same as TCAS I with the exception of providing Resolution
Advisories (RAs) integrated with the vertical speed indicator on the
PFDs and additional aural commands through the audio system. The
TCAS II system consists of a processor, two bearing antennas, and
associated airplane wiring. System control is through the radio man-
agement units. Power for the TCAS system operation is 28-vdc sup-
plied through the 5-amp TCAS circuit breaker located on the copilot's
circuit breaker panel (INSTRUMENT/INDICATIONS group).
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PM-132A