Power On Stall


Definitions:
Stall: a loss of lift due to airflow separation, brought on by exceeding the critical Angle of Attack

Angle of Attack: angle between an airfoil’s cord line, and oncoming air

Power on stall: to simulate an accidental stall occurring during takeoffs and climbs

P-factor: creates the left turning tendency in a positive angle of attack (four factors: Torque, corkscrew of slipstream, gyroscopic propeller effect, asymmetric loading)

 

Preflight Briefing:

Complete clearing turns before every performance maneuver—usually at least 180° change in direction, looking for traffic (Jeppesen Private Pilot pg. 4-6)

Power On Stall:

1. Exhibits knowledge of the elements related to power-on stalls.

2. Selects an entry altitude that allows the task to be completed no lower than 1,500 feet (460 meters) AGL.

3. Establishes the takeoff or departure configuration. Sets power to no less than 65 percent available power.

4. Transitions smoothly from the takeoff or departure attitude to the pitch attitude that will induce a stall.

5. Maintains a specified heading, ±10°, in straight flight; maintains a specified angle of bank not to exceed 20°, ±10°, in turning flight, while inducing the stall.

6. Recognizes and recovers promptly after the stall occurs by simultaneously reducing the angle of attack, increasing power as appropriate, and leveling the wings to return to a straight-and-level flight attitude with a minimum loss of altitude appropriate for the airplane.

7Retracts the flaps to the recommended setting; retracts the landing gear if retractable, after a positive rate of climb is established.

8. Accelerates to Vx or Vy speed before the final flap retraction; returns to the altitude, heading, and airspeed specified by the examiner.

General: Student should be able to explain the procedures and reasons for them.

Overview:         Why does an aircraft stall?  What happens when it stalls?  How do you prevent stalls?  How do you recover from a stall?

Emphasis:        Maintain positive control, initiate recovery promptly, and minimize loss of altitude.

Power on stall Procedure

Set Power ~75%

Flaps: either T/O or CRUISE

Vy=     68 kts T/O

75 kts CRUISE

Slowly pitch up with right rudder

Recognize buffet or wing drop

RECOVERY:

Max Power

Pitch for Horizon

Flaps = UP

Power cruise

Flight:

Technical Subject Areas:

Visual scanning/collision avoidance

Preflight preparation

Preflight procedures

Airport operations

Traffic patterns

Takeoff and climb

Power-ON- stall

  • Clearing Turns
  • Power to 75%
  • Select visual heading to maintain
  • Maintain altitude as you put the flaps down
  • Establish a climb as if taking off
  • Slowly pitch up adding right rudder
  • Recover at buffet or wing drop
  • Recover:
  • Max Power
  • Pitch to horizon
  • After reverse of trend, flaps up

After landing

Parking & securing

Special Emphasis Areas:

Positive aircraft control

Positive exchange of flight controls

Visual scanning/collision avoidance

Stall/spin awareness

Post-Flight Debriefing:

Identify tasks that were completed to standards or above.

Identify and discuss tasks that were not completed to standards.

Record and grade completed tasks in the training record

Record training in the student’s logbook (reference the Areas of Operation above).

Give an assignment for the next flight session.

 

Next Assignment: Prepare for completing this lesson by reviewing tasks that were not performed to standards. If all tasks were performed to standards, assign the next lesson’s required material.