GFC Team Agreement - CAFE Foundation

Pilot must open control loop by releasing or freezing the stick.
4) Directional stability at Va and 1.3 Vso: Performed at � 5000 feet AGL over
unpopulated areas
a. Aggressiveness: After initial, gradual familiarization with the aircraft’s controls,
assess directional stability in terms of the following sub-component goals, as
follows:
From level flight trimmed at fixed power at Va, slowly enter a sideslip by
maintaining heading with rudder and ailerons until a 10 ° bank is reached.
Note steady increase of rudder and aileron forces without force reversal as
the sideslip is increased. Then, slowly release the aileron input while still
holding full rudder, and observe whether the low wing returns to the level
position. (Do not assist the ailerons during this evaluation, maintaining
only a very light grip on the stick).
Next, check static directional stability from level flight at Va by slowly
yawing the aircraft left and right using rudder. Simultaneously, the wings
should be kept level by using the ailerons. When the rudder is released, the
aircraft should tend to return to straight ahead flight.
Repeat these maneuvers while flying trimmed at fixed power at 1.3 Vso in
the landing configuration.
b. Goals: In all sub-component goals listed in (a) above, acceptable control
performance at both Va and 1.3 Vso. This means:
Positive Cn stability with rudder force increasing in proportion to sideslip
angle no significant rudder force reversals (though lightening of force is
allowed)
No rudder lock
Low wing returns to near level when aileron input is released during
steady heading sideslips
Nose returns to near straight when rudder force is released in level yaw
tests
Damping upon such release gives no more than 3 left-right yaw oscillation
cycles
5) Static longitudinal stability at Va, stick-fixed: Performed at � 5000 feet AGL over
unpopulated areas.
• Aggressiveness: After initial, gradual familiarization with the aircraft’s controls,
assess static longitudinal stability as follows:
Trim the aircraft for level flight at Va at fixed power. Using a stick force
gauge, apply pitch input force (push) necessary to increase and then
maintain airspeed by first 5 mph, then 10, then 15 and then 20 mph.
Repeat using pitch input force (pull) necessary to decrease airspeed by 5,
then 10, then 15 and then 20 mph. Note the force in pounds necessary to
hold each of those off-trim airspeeds.
• Goals: To be acceptable, the aircraft must demonstrate progressively increasing
stick forces as airspeed deviates further from Va trim speed. The slope of an x-y
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