787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Automatic Flight Chapter 4
System Description Section 20
Copyright © The Boeing Company. See title page for details.
D615Z003-TBC 4.20.1
4.20 Automatic Flight-System Description
Automatic Flight20 System Descr iptionSystem Description
Introduction
The automatic flight control system consists of the autopilot flight director system
(AFDS) and the autothrottle system. Both the AFDS and the autothrottle are
controlled using the mode control panel (MCP) and the FMC.
Normally, the AFDS and autothrottle are controlled automatically by the FMC to
perform climb, cruise, descent, and approach flight path guidance.
Autopilot Flight Director System
The AFDS consists of three autoflight computing systems and the MCP.
The MCP provides control of the autopilot, flight director, altitude alert, and
autothrottle systems. The MCP is used to select and activate AFDS modes, and
establish altitudes, speeds, and climb/descent profiles.
The autoflight systems provide control of the flight directors and autopilot. Flight
director information is displayed on the primary flight displays (PFDs) and
head-up displays (HUDs). The AFDS does not have direct control of the flight
control surfaces. The autopilot controls the elevators, ailerons, flaperons, and
spoilers through the fly–by–wire flight control system. Autopilot rudder
commands are added only during an autopilot approach and landing. The autopilot
controls nose wheel steering during rollout after an automatic landing.
Flight director information is displayed on the primary flight displays (PFDs) and
head-up displays (HUDs). Pilot MCP selections are sent to the autopilots.
Autopilot commands are sent to the Primary Flight Computers (PFCs) to generate
flight control surface commands. While autopilot(s) is engaged the pilot controls
are back driven to provide visual and tactile indications of automatic commands.
The PFCs sends backdrive commands which control the backdrive actuators to
move the column, wheel, and pedals. Autopilot rudder commands are added only
during an autopilot approach and landing.
MCP Mode Selection
MCP mode switches are used to select automatic flight control and flight director
modes. A light on the switch illuminates to indicate that the mode is armed or
engaged. Mode engagement is indicated by the PFD and HUD roll and pitch flight
mode annunciations. Autothrottle modes are discussed later in this section.
Most modes engage with a single push. These modes include:
October 31, 2007
To Next Page
Loading...
