787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Flight Controls -
System Description
Copyright © The Boeing Company. See title page for details.
9.20.18 D615Z003-TBC
• asymmetry compensation is inoperative
• yaw damping is degraded
Spoilers
There are 7 sets of spoilers, 4 outboard and 3 inboard of the flaperons, on the upper
surface of each wing. The spoilers are numbered from left to right, 1 through 14.
Spoilers on opposing wings are symmetrically paired.
Spoiler panels are used as speedbrakes to increase drag and reduce lift, both in
flight and on the ground. The spoilers also supplement roll control in response to
control wheel commands.
All three hydraulic systems supply 5 pairs of spoilers. Each hydraulic system is
dedicated to a different set of spoiler pairs to provide isolation and maintain
symmetric operation in the event of hydraulic system failure. The remaining two
spoiler pairs are individually powered by two electrical buses.
Failure of two spoiler panels in the air, or failure of one not down and locked
spoiler panel on the ground, causes the EICAS advisory message SPOILERS to
display. Failure of three or more spoiler panels causes the EICAS advisory
message SPOILER PAIRS to display.
Spoiler Speedbrake Operation
The 14 spoiler panels are used as speedbrakes.
The speedbrake spoilers are controlled by the speedbrake lever located on the
control stand. The speedbrake lever has three marked positions:
• DOWN
•ARMED
•UP
The speedbrake lever can be placed in intermediate positions between ARMED
and UP.
In the ARMED position, the spoilers extend and the speedbrake lever is driven aft
to the UP position on landing when the main gear trucks untilt and both thrust
levers are not in the takeoff range.
When the speedbrake lever is not in the ARMED position, the spoilers still
automatically extend and the speedbrake lever is driven to the UP position when
either of the following conditions occur:
• on the ground with groundspeed above 85 knots, either thrust lever was
previously in the takeoff range, then both thrust levers are moved to the
idle range (refused takeoff), or
• on the ground and both thrust reverse levers are moved to the reverse idle
detent
February 13, 2009
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