Pitch Trim Bias; Configuration Trim - BOMBARDIER LEARJET 40 Pilot's Manual

Pilot's Manual

PITCH TRIM BIAS

The pitch trim bias system works in conjunction with the up/down
spring assembly. Its function is to assist the pilot by providing added
spring pressure against the elevator in the event the horizontal stabiliz-
er is jammed in an out-of-trim position. Pitch trim bias is actuated by
the crew using the three-position (spring loaded to the center position)
PIT TRIM BIAS switch located at the front of the throttle quadrant.
Power for the system is provided through the PIT TRIM BIAS circuit
breaker on the copilot's circuit breaker panel (FLIGHT group).
The following CAS illuminations are specific to the pitch trim bias.
CAS
PIT TRIM BIAS
PIT TRIM BIAS

CONFIGURATION TRIM

The configuration trim functions aid the pilot by providing automatic
relief of control column loads via the #1 IC control of horizontal stabi-
lizer position. The configuration trim system control and monitoring
functions are provided by software contained in the #1 IC using inputs
from spoiler lever position sensors. Through these interfaces, the con-
figuration trim provides automatic pitch control for changes in airplane
configuration. This mode is only functional when the trim selector
switch is in the PRI position and the autopilot is not engaged. Trim
commands from either control wheel trim switch will have priority
over the configuration trim commands.
5-20
Color
Red Abnormal PIT TRIM BIAS configuration with
the aircraft on the ground and either thrust
lever is advanced to MCR or above.
White The pitch trim bias system is moved from the
normal position. PIT TRIM BIAS should only
be used for jammed stabilizer conditions in
flight.
Description
PM-132A