787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Landing Gear -
System Description
Copyright © The Boeing Company. See title page for details.
14.20.4 D615Z003-TBC
Autobrake System
The autobrake system provides automatic braking at preselected deceleration rates
for landing and full pressure for rejected takeoff. Antiskid system protection is
provided during autobrake operation.
EICAS memo messages display the selected autobrake settings:
• AUTOBRAKE 1 through 4
• AUTOBRAKE MAX
• AUTOBRAKE RTO
The EICAS advisory message AUTOBRAKE is displayed if the autobrake system
is disarmed or inoperative, the AUTOBRAKE selector is OFF but the system is
armed, or an RTO is initiated above 85 knots but autobraking has not been applied.
Rejected Takeoff
Selecting RTO (rejected takeoff) prior to takeoff arms the autobrake system. The
RTO mode can be selected only on the ground. The RTO autobrake setting
commands maximum braking pressure if:
• the airplane is on the ground
• groundspeed is above 85 knots, and
• both thrust levers are retarded to idle
Maximum braking is obtained in this mode. If an RTO is initiated below 85 knots,
the RTO autobrake function does not operate.
Taxi Brake Release
During each taxi brake application, the antiskid system releases the brakes of one
axle pair of each main landing gear (if wheel speeds are less than 45 knots). The
system sequences through the axle pairs at each brake application, reducing the
number of brake applications by each brake. This extends service life and reduces
brake sensitivity during taxi.
All active brakes are applied for a heavy brake application, landing rollout, RTO,
or when setting the parking brake.
Landing
Five levels of deceleration can be selected for landing. On dry runways, the
maximum autobrake deceleration rate in the landing mode is less than that
produced by full pedal braking.
After landing, autobrake application begins when:
• both thrust levers are retarded to idle, and
• the wheels have spun up
February 15, 2010
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