Flight Control Systems

CHAPTER EIGHTEEN

T-34C AIRCRAFT SYSTEMS FAMILIARIZATION

WORKBOOK

1802. FLIGHT CONTROL SYSTEMS

The primary flight controls (rudder, elevators, and ailerons) provide the pilots a means of

controlling the aircraft from either cockpit by a conventional stick and rudder system. All

control surfaces are connected to the cockpit controls by cable/push-pull rods. There are no

power-boosted controls. Trim tabs on all control surfaces (except the right aileron) are

mechanically adjusted from either cockpit. Rudder pedals (which incorporate toe-actuated

brakes) are suspended from the rudder pedal arms and are adjustable forward and aft.

The rudder is hinged to the aft edge of the vertical stabilizer, is controlled by the rudder pedals,

and causes the aircraft to yaw around the vertical axis. The elevators are attached to the aft edge

of the horizontal stabilizer, are controlled by the control stick and cause pitch by movements

around the lateral axis. The elevator control horn has bobweights and springs, which provide

stability and a positive feel (feedback) to the stick. The ailerons, located at the aft edge, outboard

portion of each wing, are controlled by the control stick and cause roll around the longitudinal

axis.

Pilot-Operated Controls

Movement of the rudder pedals results in nose movement (yaw) left or right, i.e., left pedal

forward results in nose left movement (yaw). The rudder pedals are interconnected and move in

opposition. The control stick is pivoted at the lower end on the cockpit floor and can be

displaced any direction from vertical neutral. Movement left/right causes the aircraft to roll

left/right and forward/back stick pressure causes nose down/up pitch.

Rudder Pedal Adjustment

The position of the pedals is adjustable to compensate for pilot height difference. A hand crank

at the bottom of the instrument panel will adjust the pedals fore and aft without affecting the

setting of the rudder.

Control Lock

The control lock, located in the front cockpit, is used to secure the control surfaces. It is a

rectangular brace pivoted at two points forward and held against the floor by a spring-loaded

latch assembly. To engage the lock, release the deck latch, center the stick and adjust the pedals

slightly aft of full forward. Place the control lock on the hook on the forward side of the stick,

and adjust the pedals forward. With the lock engaged, the rudder should be aligned with the

vertical stabilizer, the elevators full down, and the ailerons neutral (both 2 down). To unlock,

reverse the procedure.

1803. SECONDARY FLIGHT CONTROLS

Secondary flight controls consist of trim tabs, strakes, and ventral fins. They affect flight

characteristics and may or may not be adjusted by the pilot.

18-2

FLIGHT CONTROL SYSTEMS