Figure 3-3. Trim Diagram

T-34C CONTACT

CHAPTER THREE

aileron trim tab in the direction you are applying stick pressure. For example, if you must hold

in right stick (the aircraft wants to roll left), roll the aileron trim wheel to the right. Generally

speaking, once the aileron trim is "fine-tuned," you may not have to retrim the ailerons for the

remainder of the flight.

Trim Requirements-Rudder/ Elevator

Acceleration............LEFT/DOWN

Power Addition........RIGHT/DOWN

Deceleration............RIGHT/UP

Power Reduction......LEFT/UP

The trim diagram (Figure 3-3) should help you understand which way to trim when airspeed and

power changes occur. However, the trim requirements must be committed to memory before

your first flight, because you will not have the time to stop and think through the trim diagram.

The center of the diagram represents equilibrium for whatever level flight condition you are

trying to maintain. When airspeed is increased (with power unchanged), we see from the trim

diagram that left rudder trim is needed and down elevator trim is needed. If power is unchanged

and airspeed is reduced, we see from the trim diagram that right rudder trim and up elevator trim

is needed. If airspeed is constant and power is increased, then right rudder trim and down

elevator trim is needed. If power is reduced with airspeed constant, then left rudder trim and up

elevator trim is necessary.

Down Elevator

Right

Left

Rudder

Up Elevator

Figure 3-3 Trim Diagram

The four trim requirements outlined in this section are basic rules. However, many situations

during a flight combine two of the "rules" simultaneously. For example, when initiating a 120-

KIAS climb from normal cruise (150 KIAS, level), you will add power, raise the nose and

decelerate. In this case, right rudder trim is required for both the power addition and

deceleration. However, the elevator trim will be nose UP, because deceleration requires a

greater amount of nose up trim than the addition of power will require nose down. The resultant

or net force is trimmed for equilibrium. More on this later......

USE AND EFFECT OF CONTROLS 3-7