# AI.XIII.C — Demonstration of Effects of Various Airspeeds and Configurations during Engine Inoperative — Flight Instructor Airplane ACS

> AI.XIII.C from FAA-S-ACS-25, including the official objective, references, notes, and 27 exact knowledge, risk-management, and skill descriptions.

Canonical HTML: [https://www.check-ride.ai/acs/airplane/flight-instructor/ai-xiii-c](https://www.check-ride.ai/acs/airplane/flight-instructor/ai-xiii-c)

Site reference: [https://www.check-ride.ai/llms.txt](https://www.check-ride.ai/llms.txt)

## Official Task context

- FAA document: Flight Instructor for Airplane Category Airman Certification Standards
- Identifier: FAA-S-ACS-25
- Published source date: November 2023
- Aircraft category: Airplane
- Certificate or rating: Flight Instructor
- Area of Operation: Area of Operation XIII. Multiengine Operations
- Task: Task C. Demonstration of Effects of Various Airspeeds and Configurations during Engine Inoperative
- Task code prefix: AI.XIII.C
- Official references: FAA-H-8083-2, FAA-H-8083-3, FAA-H-8083-9, FAA-H-8083-25; FAA-P-8740-66; POH/AFM
- FAA source library: https://www.faa.gov/training_testing/testing/acs

## Official Task objective

To determine the applicant understands the effects of various airspeeds and configurations during engine inoperative performance, can apply that knowledge, manage associated risks, demonstrate appropriate skills, and provide effective instruction.

## Knowledge elements

- **AI.XIII.C.K1** — Purpose for and elements of demonstration of effects of various airspeeds and configurations during engine inoperative performance.
- **AI.XIII.C.K2** — Selection of appropriate altitude for the demonstration.
- **AI.XIII.C.K3** — Proper entry procedure to include pitch attitude, bank attitude, and airspeed.
- **AI.XIII.C.K4** — Effects on performance of airspeed changes at, above, and below VYSE.
- **AI.XIII.C.K5** — Effects on performance of various configurations including:
- **AI.XIII.C.K5a** — a. Landing gear extended
- **AI.XIII.C.K5b** — b. Wing flaps extended
- **AI.XIII.C.K5c** — c. Landing gear and wing flaps extended
- **AI.XIII.C.K5d** — d. Windmilling propeller on the inoperative engine
- **AI.XIII.C.K6** — Airspeed control throughout the demonstration.
- **AI.XIII.C.K7** — Smooth control technique and coordination throughout the demonstration.
- **AI.XIII.C.K8** — Common errors related to this Task.

## Risk management elements

- **AI.XIII.C.R1** — Altitude selection.
- **AI.XIII.C.R2** — Entry and recovery procedures.
- **AI.XIII.C.R3** — Loss of control or stall.
- **AI.XIII.C.R4** — Configuring the airplane.
- **AI.XIII.C.R5** — Collision hazards.
- **AI.XIII.C.R6** — Distractions, task prioritization, loss of situational awareness, or disorientation.

## Skills elements

- **AI.XIII.C.S1** — Demonstrate, describe, and explain effects of various airspeeds and configurations during engine inoperative performance.
- **AI.XIII.C.S2** — Demonstrate smooth control inputs when transitioning between various airspeeds and configurations, which include:
- **AI.XIII.C.S2a** — a. Landing gear extended
- **AI.XIII.C.S2b** — b. Wing flaps extended
- **AI.XIII.C.S2c** — c. Landing gear and wing flaps extended
- **AI.XIII.C.S2d** — d. Windmilling propeller on the inoperative engine
- **AI.XIII.C.S3** — Maintain appropriate airspeed, attitude, and altitude combinations for the various configurations.
- **AI.XIII.C.S4** — Return to normal cruise flight at the altitude and heading specified by the evaluator.
- **AI.XIII.C.S5** — Analyze and correct common errors related to this Task.

## Difficulty methodology

Difficulty calibration is ongoing for this Task. Observed difficulty is a privacy-thresholded check-ride.ai mock-oral practice proxy, not an FAA practical-test pass or fail rate. Underlying sample sizes and the private reporting threshold are not published.

## Official Task notes

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

## Use in practice

A mock examiner can ask a pilot to explain the published elements, apply them to the configured aircraft and airport context, identify risks, and defend a decision. Practice prompts are not represented as actual FAA examiner scripts or predictions of the questions a candidate will receive.