787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Flight Controls Chapter 9
System Description Section 20
Copyright © The Boeing Company. See title page for details.
D615Z003-TBC 9.20.1
9.20 Flight Controls-System Description
Flight Cont rols20 System DescriptionSystem Description
Introduction
The primary flight control system uses conventional control wheel, column, and
pedal inputs from the pilot to electronically command the flight control surfaces.
The system provides conventional control feel and pitch responses to speed and
trim changes. The system’s electronic components provide enhanced handling
qualities and reduce pilot workload.
The primary flight control system is highly redundant, with three operating
modes: normal mode, secondary mode, and direct mode.
Pilot Controls
The pilot controls consist of:
The columns, wheels, and rudder pedals are connected through jam override
mechanisms. If a jam occurs in a column, wheel, or rudder pedals the pilots can
maintain control by applying force to the other column, wheel, or rudder pedals to
overcome the jam.
The speedbrake lever allows manual or automatic symmetric actuation of the
spoilers.
The EICAS caution message FLIGHT CONTROLS is displayed if:
• multiple ACE and/or hydraulic system failures cause the loss of a
significant number of control surfaces, or
• other significant flight control system faults are detected
The ACEs can transmit pilot control inputs directly to the control surfaces, or they
can send the pilot inputs to the PFCs. When the ACEs are sending pilot inputs to
the PFCs, the ACEs receive control commands back from the PFCs and use the
commands to position the flight control surfaces.
The PFCs use information from other airplane systems (such as air data, inertial
data, flap and slat position, engine thrust, and radio altitude) to compute control
surface commands for enhanced handling qualities. See Primary Flight Control
System Modes in this Section for a description of these handling quality
enhancements.
• alternate flap switches
• alternate pitch trim switches
• control wheel pitch trim switches
• rudder trim selector
• stabilizer cutout switches
• the flap lever
• the speedbrake lever
• two control columns
• two control wheels
• two pairs of rudder pedals
February 15, 2010
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