Partial Flap Configuration Stall Prevention

Because the event being graded is the impending stall, not the break. AC 120-109 defines an impending stall as an AOA that causes a stall warning — the same thing the AC calls "approach-to-stall" or "the first indication of stall." The Task requires you to acknowledge the cue(s) and promptly recover at the first indication of an impending stall — buffet, stall horn, stick shaker (AA.V.A.S5). You are being checked on recognition and response, not on riding it into a full stall.

Not for this Task. AC 120-109 para 4-2a is explicit: in maneuver-based stall prevention training and checking, pilots should apply the stall recovery at stall warning as defined in para 1-7 — not at a low speed alert or low energy alert (e.g., "airspeed low, airspeed low," "speed, speed, speed," or a flashing airspeed warning cue). Starting the recovery at the low-speed alert does not satisfy the objective of training or checking the recovery procedure, so an otherwise clean recovery can be graded as the maneuver not having been performed. Two caveats worth saying out loud: in scenario-based training the opposite applies — you should return the airplane to a desired state on any low airspeed or low energy alert; and on the line, an energy alert is exactly what you want to act on, since this is a checking-context rule, not an airmanship rule.

This is the practical edge of AA.V.A.R2 (range and limitations of stall warning indicators) and R3 (stall warning awareness): know which of your annunciations is a stall warning and which is merely a low energy alert.

• Clear the area and pick an entry altitude that lets the recovery finish no lower than 3,000 feet AGL (non-transport category) or 5,000 feet AGL (transport category) (AA.V.A.S1)
• Bank angle 15°–30°, adjusted smoothly along with pitch and power per the evaluator's instructions, to an impending stall (AA.V.A.S4)
• Coordinated flight maintained in simulated or actual instrument conditions throughout the maneuver (AA.V.A.S3)

Note what is not there: no altitude-loss number, no airspeed tolerance, no heading tolerance. That absence is deliberate.

No — and it is a core principle of the guidance, not an oversight. Evaluation criteria for a recovery from an impending stall should not include a predetermined value for altitude loss; criteria should instead consider the multitude of external and internal variables that affect the recovery altitude. Para 4-5 gives the three checking criteria instead:

• Prompt recognition of the impending stall
• Correct application of the stall recovery procedure
• Recovering without exceeding the airplane's limitations

Pilots must accept that reducing AOA will normally result in altitude loss.

1. Autopilot and autothrottle/autothrust — disconnect. Manual control is essential in all situations.
2. Pitch — a) nose-down pitch control, apply until impending stall indications are eliminated; b) nose-down pitch trim, as needed.
3. Bank — wings level. This orients the lift vector for recovery.
4. Thrust — as needed. Maximum thrust is not always needed.
5. Speed brakes/spoilers — retract. Improves lift and stall margin.
6. Return to the desired flightpath with gentle action, to avoid secondary stalls.

(AC 120-109, Appendix 1, Table 1.) The Task itself requires the recovery in accordance with the POH/FM for your airplane (AA.V.A.S6) — the template is the fallback when the manufacturer has not published a procedure.

Because thrust does not fix AOA, and in some airframes it makes the AOA worse. AC 120-109 eliminated the old profiles that emphasized immediate advancement of maximum thrust — a stall can occur at high thrust or idle thrust, so thrust is adjusted accordingly. Three airframe types react differently:

• Engines below the wing: applying maximum thrust may create a strong nose-up pitching moment at low airspeed
• Engines above the wing: thrust creates a helpful pitch-down tendency
• Propeller-driven airplanes: thrust application increases the airflow around the wing, assisting in stall recovery

Know which of those three your airplane is.

An abrupt pitch-up or trim change can occur when the autopilot unexpectedly disconnects during a stall event, adding an unexpected physical challenge exactly when you are trying to reduce AOA. In some airplanes this is aggravated by an additional pitch-up when the pilot increases thrust during the recovery (AC 120-109, para 4-2). On a departure, the airplane is already trimmed nose-up, thrust is high, and underwing engines add their own couple — so step 1 (disconnect) and step 2b (nose-down trim as needed) are doing real work, not ceremony.

AC 120-109 defines a secondary stall as a premature increase in AOA producing another full stall during the recovery, before a stable flight condition is established; a secondary stall warning is simply a reoccurrence of the stall warning. The AC is blunt about diagnosis: secondary stall warnings are indicative of a pilot prioritizing minimum loss of altitude over proper stall recovery, or of flight control inputs that are too aggressive.

But do not read it as an automatic bust: in some airplanes it may be difficult to determine the point where pitch can begin to be increased, and a secondary stall warning is acceptable as long as AOA is promptly reduced and the airplane's limitations are not exceeded (para 4-2a). What the evaluator is grading is whether you reduced AOA promptly and stayed inside the limits — not whether the warning chirped a second time.

Range: a stick shaker is an artificial stall warning device that vibrates the control column (AFH glossary) and normally activates around 107 percent of the actual stall speed (AFH ch. 16) — a thin margin, not a comfortable buffer. Part 25 requires stall warning to be clear and distinctive to the pilot in straight and turning flight (25.207(a)); AC 120-109's own definition adds that the alert — aerodynamic buffet or a synthetic cue — must give clear indications prior to a full stall to allow a pilot to prevent a full stall (para 1-7o, which points at 25.207).

Limitation: airplanes without vortex generators may stall with little to no buffet (AFH ch. 16), so aerodynamic cues can be nearly absent; malfunctioning or deferred equipment can also degrade stall protection and stick pusher systems (AC 120-109, para 4-2).

AA.V.A.K2 asks for recognition using sight, sound, or feel, and AC 61-67 catalogs the raw cues:

• Feel — a mushy feeling in the flight controls and less control effect as speed is reduced, attributed in part to reduced airflow over the control surfaces; kinesthesia — the sensing of changes in direction or speed of motion — warns of a decrease in speed or the beginning of a mushing
• Sound — a reduction in the sound of air flowing along the fuselage; in fixed-pitch propeller airplanes, a loss of rpm in power-on conditions
• Buffet — just before the stall: buffeting, uncontrollable pitching, or vibrations
• Synthetic — stall warning devices that alert the pilot 4 to 8 knots prior to the onset of the stall

When one or more of these indicators is noted, initiation of a recovery should be instinctive (AC 61-67, para 103) — which is the S5 standard in different words: acknowledge the cue, recover promptly.

AC 120-109 lists any one or combination of:

• An uncommanded nose-down pitch that cannot be readily arrested, possibly with an uncommanded rolling motion
• Buffeting of a magnitude and severity that is a strong and effective deterrent to further increase in AOA
• No further increase in pitch when the pitch control is held at the full aft stop for 2 seconds, leading to an inability to arrest descent rate
• Activation of a stick pusher

On the ATP practical test you are not being asked to produce any of these — a full stall in the partial flap configuration means you missed the cue.

121.423, Pilots: Extended Envelope Training. It requires instructor-guided hands-on experience of recovery from full stall and stick pusher activation, if equipped (121.423(c)), conducted in a Level C or higher full flight simulator (121.423(a)). Recurrent extended envelope training is required within 24 calendar months preceding service as a pilot for the stall, upset, slow flight, unreliable airspeed, and manual departure/arrival items, and within 36 calendar months for recovery from a bounced landing (121.423(d)). AC 120-109 explicitly reflects the full stall training requirement of Public Law 111-216.

• Windshear or a microburst on departure or a low approach — performance loss the crew tries to fly through with pitch
• Turbulence and high density altitude eroding the margin between the current and the critical AOA (AA.V.A.R6)
• A level-off or altitude capture with thrust still at climb and the flight director commanding pitch the thrust cannot support
• A premature or unbriefed flap retraction below the maneuvering speed for the next configuration
• Distraction and task saturation during a config change — the ACS names distractions, task prioritization, loss of situational awareness, and disorientation as risks (AA.V.A.R8). The emphasis is earned: stall/spin accidents account for roughly one-quarter of all fatal general aviation accidents, and NTSB statistics indicate most result when a pilot is momentarily distracted from the primary task of flying (AC 61-67)
• Sideslip from an unfeathered or asymmetric-thrust condition, which AA.V.A.K1 calls out specifically for this Task

Compare the knowledge elements: AA.V.A.K1 and AA.V.C.K1 both list sideslip effects among the relationships you must understand; AA.V.B.K1 (clean) does not. The reason is operational — the partial flap and landing configurations are the ones flown near the ground with asymmetric thrust, crosswind corrections, and rudder trim in play. Uncoordinated flight at high AOA is how an impending stall becomes a spin, and the ACS lists inadvertent stall, spin, and loss of control during takeoff or while on approach as the risk (AA.V.A.R1). The skill element answers it: coordinated flight throughout the maneuver (AA.V.A.S3).

AC 61-67 names the scenario directly: a go-around or short field takeoff — high pitch attitude, high power setting, and low airspeed — is the classic situation where P-factor (asymmetric propeller loading) can precipitate a stall/spin accident. At high AOA the downward-moving blade carries a higher AOA and more thrust, yawing the airplane left; insufficient or excessive rudder correction leaves the airplane uncoordinated. Two compounding traps apply (AC 61-67, para 109): in an uncoordinated maneuver the pitot/static instruments — especially the altimeter and airspeed indicator — are unreliable, so the stall warning may be your first honest cue that a critical AOA is approaching; and if a stall recovery is not promptly initiated, the airplane is more likely to enter an inadvertent spin, the primary cause of which is exceeding the critical AOA while applying excessive or insufficient rudder.

The jet-era version swaps P-factor for the underwing thrust couple, but the risk it grounds is the same one the ACS names: inadvertent stall, spin, and loss of control during takeoff or while on approach (AA.V.A.R1).

The entry changes; the recovery does not. AC 120-109 directs that training include disconnecting the autopilot and autothrottle/autothrust during stall prevention training and, where the autoflight integration permits, scenarios with the autothrottle/autothrust engaged. With the autopilot flying the entry, the airplane arrives at the stall warning already trimmed well nose-up, which is precisely the out-of-trim condition step 1 of the template warns about — you must ensure the pitch attitude does not increase when disconnecting the autopilot. Expect to need forward column force and nose-down trim.

The honest answer for the oral is type-specific — it belongs to your AFM and FSB report, not a memorized generality. AA.V.A.K4 requires knowledge of flight envelope protection in normal and degraded modes and of unexpected disconnects of the autopilot or autothrottle/autothrust: protections vary by manufacturer and by control law, and a degraded law may hand you an airplane with no alpha protection at all. AC 120-109 directs operators to consult the FSB report for the specific type, reviewing the Training Areas of Special Emphasis and any stall-related recommendations (para 2-6). Say what your airplane does; never generalize.

Treat it as a memory-item maneuver with a division of labor:

• The pilot flying announces the recovery ("stall — my controls" or the operator's phrasing), disconnects the autopilot and autothrottle/autothrust, and applies nose-down pitch until the warning stops
• The pilot monitoring confirms the disconnects, calls the airspeed and altitude trend, sets thrust as directed, and retracts speed brakes/spoilers
• Configuration changes are commanded and confirmed, not silent — the Task requires flaps and other lift/drag devices to the recommended setting, and the landing gear retracted after a positive rate of climb is established, if applicable (AA.V.A.S7)

Fly your operator's published callouts; the point is that both pilots must be able to state the sequence out loud.

Priority order (AC 120-109, para 4-2):

1. Recognize the stall and return the airplane to a controlled, safe state — the most important factor in surviving a stall event
2. Recover to a safe maneuvering speed and AOA
3. Re-establish the assigned heading, altitude, and airspeed
4. Return to the desired flight path as specified by the evaluator (AA.V.A.S7)

Chasing the clearance during the recovery is how a stall event becomes an accident.