Power-On Stalls

4.power-on-stalls. Power-On Stalls

Power-on stalls (also called departure stalls) are practiced to simulate the conditions and aircraft attitudes most likely to result in an inadvertent stall during takeoff, climb-out, or a go-around. In these phases, the airplane is at a high pitch attitude, low airspeed, and high power setting — exactly the configuration that produces a critical angle of attack with little warning if the pilot mismanages pitch or rudder. Recognition, recovery, and prevention of this stall are required maneuvers under the Airman Certification Standards (ACS) for the private and commercial pilot certificates.

Purpose and Configuration

The maneuver demonstrates the airplane's behavior at the high angles of attack associated with takeoff and initial climb. The airplane is configured to mirror those phases of flight:

• Takeoff configuration: flaps and gear as recommended for normal/short-field takeoff (often flaps up or first notch, per the POH).
• Departure climb configuration: clean (flaps and gear retracted).

Power is normally set to takeoff power for the practice. In airplanes with a high power-to-weight ratio, the manufacturer or the ACS may permit reduced power (typically not less than 65% available power) to keep the pitch attitude within reasonable limits and prevent excessive altitude gain.

Required Clearing and Altitude

Before beginning, the pilot should:

• Complete clearing turns to scan for traffic.
• Select an altitude that allows recovery no lower than 1,500 feet AGL for single-engine airplanes (3,000 feet AGL for multiengine), per the ACS.
• Note a prominent reference heading; the maneuver is usually entered from straight-and-level or from a shallow bank of up to 20°.

Entry Procedure

1. From cruise, reduce power and slowly raise the nose to maintain altitude, allowing airspeed to decay to the manufacturer's recommended lift-off or climb speed (commonly VR or VY — for many trainers, around 55–65 KIAS).
2. Once at the target airspeed, smoothly apply takeoff power (or the briefed reduced setting) while simultaneously increasing pitch to a climb attitude that will induce a stall.
3. Maintain the selected bank (wings-level or up to 20°) using coordinated aileron and rudder. Right rudder is critical to counteract left-turning tendencies (torque, P-factor, slipstream, and gyroscopic precession) at high power and high angle of attack.
4. Continue increasing back-elevator pressure until the stall occurs. Recognize the aerodynamic indications:
   • Decay of control effectiveness
   • Aerodynamic buffet
   • Stall warning horn or light
   • Full break (or first indication, depending on ACS task)

Recovery Procedure

The FAA-standard stall recovery template applies. The pilot must promptly and decisively:

1. Reduce angle of attack by positively releasing back pressure and lowering the nose to break the stall. This is the single most important step — without reducing AOA, no other action will recover the airplane.
2. Level the wings with coordinated aileron and rudder.
3. Adjust power as necessary (already at full power in this maneuver, but be alert for engine considerations such as exceeding limits).
4. Return to the desired flight path with a smooth pitch-up to climb attitude, avoiding a secondary stall.
5. Retract flaps/gear on the manufacturer's schedule once a positive rate of climb is established.

Minimum altitude loss is desirable, but recovery from the stalled condition takes priority over altitude. A typical well-flown power-on stall recovery loses 100–200 feet.

Common Errors

• Uncoordinated flight at the stall, allowing a wing to drop and possibly entering an incipient spin. Maintaining coordination with the ball centered is essential.
• Failure to recognize the first aerodynamic indications, leading to a deeper stall than intended.
• Excessive back-pressure during recovery causing a secondary stall.
• Using ailerons rather than rudder to pick up a dropping wing — this can aggravate the stall on the down-going wing.
• Inadequate right rudder during entry, causing yaw and roll to the left.
• Recovery initiated before reaching the full stall (when full stall is required by the task).

Aerodynamic Considerations

A stall occurs when the wing exceeds its critical angle of attack, regardless of airspeed, attitude, or power. In a power-on stall, thrust contributes a vertical component because of the high pitch attitude, allowing the airplane to maintain altitude (and even climb) at airspeeds well below the published 1G stall speed. This often produces a more abrupt break and a stronger tendency to roll because of asymmetric thrust effects. Pilots should expect the nose to fall through the horizon decisively at the break — releasing back pressure to reduce AOA, not pushing aggressively forward, prevents negative-G excursions and zero-G induced engine issues.