Out-of-Control Flight
Out-of-Control Syllabus Maneuvers
HIGH AOA/DEEP STALL INVESTIGATION/RUDDER-INDUCED DEPARTURE
You will begin with an exploration of the fully stalled characteristics of the T-45. Previously, you have
practiced stalls to learn recognition and recovery from the onset of the stall. This maneuver will demon-
strate the flight characteristics much farther into the stall, up to approximately 30 units AOA.
Before entering a high AOA/deep stall condition, you should know what indications to expect. You will not
necessarily experience all of the following indications of deep stall, nor will you experience them in any
particular sequence:
*
Increasingly heavier buffeting as stall deepens
*
Increasingly heavier buffeting as stall deepens
*
Yaw rate
*
Increasing sink rate
*
Wing drop
*
Reduced lateral control
Start above 20,000 ft with landing gear, flaps/slats, and speed brakes retracted. Reduce power to IDLE
rpm and raise the nose 10 degrees to trade altitude for airspeed as the aircraft slows to 20 units AOA. Do
not trim past 150 KIAS. You should notice that the rudder and aileron effectiveness will be adequate at 20
units.
As you increase AOA, you will get the rudder shakers at 21.5 units. As you slowly increase the AOA to
24-26 units, you will experience your first buffet and wing drop with very little warning. At 25-26 units AOA,
the aircraft will be in light to moderate buffet, and you may encounter mild porpoising. Notice that the
rudder and aileron effectiveness are reduced. Notice the adverse yaw generated by aileron deflection.
Increase the AOA to 28-30 units by smoothly but firmly applying full back stick. You will experience heavy
buffet, wing drop, stall noise, and a large sink rate. Airspeed will be approximately 110-120 KIAS. The
aircraft is fully stalled, and aileron effectiveness is marginal. Attempt to maintain wings level with rudder
only; do not use aileron to counter any roll tendencies. If the aircraft rolls into an angle of bank of 90
degrees or more, then recover. If you are able to hold wings level with rudder, you will induce a departure
with rudder only: Maintain full back stick and input half rudder in one direction to achieve greater than 30
degrees AOB. Then, try to return to level flight by inputting full rudder in the opposite direction. The
aircraft should start to roll in the direction of the last rudder input, then quickly roll back into the initial
direction and depart.
As the aircraft departs, perform your OCF procedures. The aircraft will quickly recover, and airspeed will
begin to build. Recover to the nearest horizon at 150 KIAS with AOA between 5 and 20 units by rolling
wings level and commencing an optimum AOA pullout (17 units). Avoid pulling into an accelerated stall
during recovery. Then check OIL PRESS light out, and set power for next maneuver.
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