BOMBARDIER Challenger 601-3A CL-600-2B16 Pilot Training Manual page 384

A wear indicator pin on each brake assembly
provides visual indication of brake wear. When
the end of the pin is flush with the spring hous-
ing (Figure 14-13), the brake assembly must
be replaced. Brake pressure must be applied
to check the wear indicator pin.
An antiskid system, when armed, allows the
brakes to stop the airplane in the shortest pos-
sible distance under all runway conditions.
Parking brakes can be set from the cockpit.
Figure 14-13. Measurement of Brake Wear
ANTISKID SYSTEM
The antiskid system, operative above 10 knots,
includes a control unit, antiskid valves, wheel
speed sensors, and associated controls and in-
dicators. The system independently controls
braking of each main landing gear wheel by
varying the hydraulic pressure applied. The
system incorporates the following features:
• Modulated skid protection for each wheel
• Locked wheel protection
CL-600-2B16 PILOT TRAINING MANUAL
The system is armed with a switch on the an-
tiskid panel, provided the parking brakes are
not set and the landing gear control unit indi-
cates that the nose gear is down and locked.
When the wheel deceleration rate exceeds a
predetermined reference level, the applicable
antiskid valve modulates braking pressure to
relieve the skid tendency. After each modu-
lation, pressure again increases at a controlled
rate. This cycle action may occur as often as
10 times per second, depending on runway
conditions and brake application by the pilot.
Touchdown protection is provided to prevent
brake application by either pilot prior to touch-
down. When airborne, the WOW system en-
ergizes the antiskid valves, dumping braking
pressure. At touchdown, wheel spinup above
35 knots overrides the WOW system, and an-
tiskid braking is immediately available. If a
wheel fails to spin up at touchdown, or if un-
usual runway conditions cause a heavy skid,
locked-wheel circuitry provides pressure
dumping from that wheel.
The amber INBD FAIL light on the antiskid
panel comes on if a failure occurs in the in-
board brake antiskid system, or if the parking
brake shutoff valve fails to open with the gear
down and locked. Illumination of the amber
OUTBD FAIL light indicates failure in the
outboard brake antiskid system.
System testing is accomplished with the
TEST switch on the antiskid panel (Figure
14-14). The parking brakes must be off, the
ANTI-SKID switch in the ARM position,
and the gear down and locked. Press the
TEST button; all four lights illuminate.
Releasing the TEST button causes all four
lights to extinguish; any light remaining
illuminated indicates a system fault.
FOR TRAINING PURPOSES ONLY
FlightSafety Canada
• Touchdown protection
• Built-in testing capability
Lt é e
Lt d .
CL 601-3A/R 14-11