IL.XII.D — Accelerated Stalls

IL.XII.D for the Flight Instructor Powered Lift ACS: official objective, references, and 25 exact knowledge, risk-management, and skill descriptions.

FAA-S-ACS-27, November 2023. This study page does not replace the current FAA publication or an examiner's plan of action.

Official task context

IL.XII.D official ACS context
Certificate or ratingFlight Instructor
Aircraft categoryPowered Lift
Area of operationArea of Operation XII. Slow Flight and Stalls
TaskTask D. Accelerated Stalls
Task code prefixIL.XII.D
Official referencesAC 61-67; FAA-H-8083-2, FAA-H-8083-9, FAA-H-8083-25; Flight Manual
FAA documentFAA-S-ACS-27 — Flight Instructor for Powered-Lift Category Airman Certification Standards
FAA source libraryOpen the official ACS library

Official task objective

To determine the applicant understands accelerated stalls (power-on and power-off), can apply that knowledge, manage associated risks, demonstrate appropriate skills, and provide effective instruction.

What the ACS code means

  • IL identifies the ACS standard family used for this Flight Instructor Powered Lift document.
  • XII identifies Slow Flight and Stalls, the Area of Operation.
  • D identifies Accelerated Stalls, the Task within that Area.
  • K, R, and S identify knowledge, risk-management, and skill elements. The number selects the item; a trailing lowercase letter identifies a listed sub-element.

Knowledge elements

Official ACS knowledge items and mock-oral treatment
ACS codeOfficial descriptionHow a mock oral can probe it
IL.XII.D.K1Purpose of and procedures for accelerated stalls.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
IL.XII.D.K2Aerodynamics associated with stalls in various aircraft configurations, including the relationship between angle of attack, airspeed, load factor, power setting, aircraft weight and center of gravity, aircraft attitude, and yaw effects.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
IL.XII.D.K3Stall characteristics as they relate to aircraft design, and recognition impending stall and full stall indications using sight, sound, or feel.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
IL.XII.D.K4Factors leading to an accelerated stall and preventive actions.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
IL.XII.D.K5Fundamentals of stall recovery.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
IL.XII.D.K6Common errors related to this Task.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.

Risk management elements

Official ACS risk management items and mock-oral treatment
ACS codeOfficial descriptionHow a mock oral can probe it
IL.XII.D.R1Factors and situations that could lead to an inadvertent accelerated stall, spin, and loss of control.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
IL.XII.D.R2Range and limitations of stall warning indicators (e.g., aircraft buffet, stall horn, etc.).Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
IL.XII.D.R3Stall warning(s) during normal operations.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
IL.XII.D.R4Stall recovery procedure.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
IL.XII.D.R5Secondary stalls and accelerated stalls.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
IL.XII.D.R6Effect of environmental elements on aircraft performance related to power-on stalls (e.g., turbulence, microbursts, and high-density altitude).Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
IL.XII.D.R7Collision hazards.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
IL.XII.D.R8Distractions, task prioritization, loss of situational awareness, or disorientation.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.

Skills elements

Official ACS skills items and mock-oral treatment
ACS codeOfficial descriptionHow a mock oral can probe it
IL.XII.D.S1Clear the area.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S2Select an entry altitude that allows the Task to be completed no lower than 3,000 feet AGL or as recommended by the manufacturer, whichever is higher.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S3Establish the takeoff, departure, or wing-borne configuration, as specified by the evaluator, and maintain coordinated flight throughout the maneuver.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S4Set power as assigned by the evaluator.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S5Establish and maintain a coordinated turn in a 45° bank (or as limited by the manufacturer), increasing elevator back pressure smoothly and firmly until an impending stall is reached.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S6Acknowledge the cues at the first indication of a stall (e.g., aircraft buffet, stall horn, etc.).Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S7Recover at the first indication of a stall.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S8Configure the aircraft as recommended by the manufacturer and accelerate to VX or VY.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S9Return to the altitude, heading, and airspeed specified by the evaluator.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S10Use single-pilot resource management (SRM) or crew resource management (CRM), as appropriate.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
IL.XII.D.S11Analyze and correct common errors related to this Task.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.

Difficulty data

Difficulty calibration is ongoing for this Task. A difficulty estimate is published only with a sufficiently large, privacy-preserving first directly recorded assessment sample. Any observed difficulty comes from Checkride AI mock-oral practice assessments and is a practice-data proxy, not an FAA practical-test pass or fail rate.

Difficulty calibration remains ongoing until an item clears the private reporting threshold. Percentages, when available, describe the share who needed review on their first directly recorded assessment. Underlying sample sizes are never published, and historical final states are not backfilled into this measure.

Official task notes

  • Note: See Appendix 2: Safety of Flight and Appendix 3: Aircraft, Equipment, and Operational Requirements & Limitations for information related to this Task.

How to use this in a mock oral

A mock examiner can ask you to explain the published elements, apply them to the configured aircraft and airport scenario, identify risks, and defend a decision. The prompts are practice scenarios; they are not claimed to be actual FAA examiner scripts or a prediction of the questions you will receive.

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