Performance - P-8680024

CHAPTER TWO

T-6A CONTACT

When airspeed is increased (with power unchanged), the nose will have a tendency to rise and

the aircraft will yaw slightly to the right; consequently, we need to add left (rudder) and down

(nose down) trim. If power is unchanged and airspeed is reduced, we see from the box above

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 are necessary.

Aside from these four basic scenarios, many flight maneuvers combine two of the "rules"

simultaneously. For example, when initiating a 180 knot climb from normal cruise (200 knots,

level), you add power, raise the nose, and decelerate. In this case, right rudder trim is required

for both the power addition and deceleration. However, the requirement conflicts on what to do

with the elevator (power addition = nose down/deceleration = nose up). In this example, trim

"nose up" because, generally speaking, in opposing situations such as this one, airspeed will have

a greater and more lasting effect on the elevator and rudder trim. Therefore, as a common trim

rule, "Airspeed trumps Power."

204.

PERFORMANCE

Remember this simple formula: POWER + ATTITUDE = PERFORMANCE

Most early basic air work problems result from the inability to properly see and control the

aircraft's attitude, in correlation to the power applied by the engine. Only after you master proper

attitude control will you begin to develop solid basic flying skills.

Coordinated use of all controls is very important in any turn. Applying aileron pressure places

the aircraft in the desired angle of bank (AOB), while simultaneous application of rudder

pressure is required to counteract the resultant adverse yaw. During a turn, the AOA must be

increased by adding back stick pressure (increasing elevator deflection) to compensate for the

loss of lift due to bank. Thus, the steeper the turn, the more back elevator pressure is needed to

maintain level flight, accompanied by a corresponding increase in G load. Varying greatly among

different flight regimes, the actual amount of deflection of the control surfaces is of little

importance as long as you reach the desired result.

When using the rudder pedals, pressure should be applied smoothly and evenly by pressing with

the ball of one foot just as when using the brakes of an automobile. The rudder pedals are

interconnected and act in opposite directions; when pressure is applied to one pedal, pressure on

the other must be relaxed proportionally. For positioning, comfortably rest the balls of your feet

against the lower portion of the rudder pedals while supporting the weight of your feet on the

cockpit floor. The pedals should be adjusted so that full throw is available with a slight flex in

the knee.

2-6

THE FLIGHT CONTROLS