surfaces control system; the angle-of-attack system;
responds to fore-and-aft manual inputs at the control
and the speed brake control system. Because of the
stick and to automatic flight control system inputs
complexity of the F-14 flight control systems, only a
introduced at the stabilizer actuator. The actuator can
brief description is presented.
operate in three modes: manual, series, or parallel.
RUDDER CONTROL (YAW AXIS).--Rudder
Manual Mode.--In this mode, pilot input alone
control, which affects the yaw axis, is provided by way
controls the power valve.
of the rudder pedals. Rudder pedal movement is
Series Mode.--In this mode, input signals from
mechanically transferred to the left and right rudder
the automatic flight control system (AFCS) may be
servo cylinders by the rudder feel assembly, the yaw
used independently or combined with manual inputs to
summing network, and a reversing network.
control stabilizer movement.
SPOILER CONTROL (LATERAL AXIS).--
Parallel Mode.--In this mode, input signals from
Spoiler control is provided through the control stick
the AFCS alone control stabilizer movement.
grip, roll command transducer, roll computer, pitch
computer, and eight spoiler actuators (one per spoiler).
Directional Control Systems
The spoilers, when used to increase the effect of
roll-axis control can only be controlled when the wings
Directional control systems provide a means of
are swept forward of 57 degrees. Right or left
controlling and stabilizing the aircraft about its vertical
movement of the control stick grip is mechanically
axis. Most aircraft use conventional rudder control
transferred to the roll command transducer, which
systems for this purpose. The rudder control system is
converts the movement to inboard and outboard spoiler
operated by the rudder pedals in the cockpit, and is
powered hydraulically through the power mechanism.
In the event of hydraulic power failure, the hydraulic
DIRECT LIFT CONTROL (DLC).--DLC
portion of the system is bypassed, and the system is
moves the spoilers and horizontal stabilizers to increase
powered mechanically through control cables and
aircraft vertical descent rate during landings without
linkage. When the pilot depresses the rudder pedals, the
changing engine power.
control cables move a cable sector assembly. The cable
WING SURFACE CONTROL SYSTEM.--The
sector, through a push-pull tube and linkage, actuates
wing surface control system controls the
the power mechanism and causes deflection of the
variable-geometry wings to maximize aircraft
rudder to the left or right.
performance at all speeds and altitudes. The system
also provides high lift and drag forces for takeoff and
F-14 Flight Control Systems
landing, and increased lift for slow speeds. At
supersonic speeds, the system produces aerodynamic
The F-14 flight control systems include the rudder,
lift to reduce trim drag.
the stabilizer, and the spoiler control systems; the wing
Figure 2-7.--Wing sweep control system (F-14).