# IL.X.B — Inflight Conversion During Straight-and-Level Flight — Flight Instructor Powered Lift ACS

> IL.X.B from FAA-S-ACS-27, including the official objective, references, notes, and 22 exact knowledge, risk-management, and skill descriptions.

Canonical HTML: [https://www.check-ride.ai/acs/powered-lift/flight-instructor/il-x-b](https://www.check-ride.ai/acs/powered-lift/flight-instructor/il-x-b)

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

## Official Task context

- FAA document: Flight Instructor for Powered-Lift Category Airman Certification Standards
- Identifier: FAA-S-ACS-27
- Published source date: November 2023
- Aircraft category: Powered Lift
- Certificate or rating: Flight Instructor
- Area of Operation: Area of Operation X. Performance Maneuvers
- Task: Task B. Inflight Conversion During Straight-and-Level Flight
- Task code prefix: IL.X.B
- Official references: FAA-H-8083-2, FAA-H-8083-9, FAA-H-8083-25; Flight Manual
- FAA source library: https://www.faa.gov/training_testing/testing/acs

## Official Task objective

To determine the applicant understands converting from thrust-borne configuration to wing-borne configuration, and returning to thrust-borne configuration, and can apply that knowledge, manage associated risks, demonstrate appropriate skills, and provide effective instruction.

## Knowledge elements

- **IL.X.B.K1** — Procedures for changing aircraft configuration.
- **IL.X.B.K2** — Aerodynamic effects of changing aircraft configuration.
- **IL.X.B.K3** — Flight control operation when converting from thrust-borne to wing-borne configuration, and when converting from wing-borne to thrust-borne configuration, while in straight-and-level flight.
- **IL.X.B.K4** — Aircraft performance and limitation charts.
- **IL.X.B.K5** — Factors related to weight and balance and center of gravity (CG) envelopes.
- **IL.X.B.K6** — Common errors related to this Task.

## Risk management elements

- **IL.X.B.R1** — Aircraft performance limitations.
- **IL.X.B.R2** — Powerplant failure during conversion.
- **IL.X.B.R3** — Aerodynamic stall.
- **IL.X.B.R4** — Effects of gross weight and CG.
- **IL.X.B.R5** — Rapid configuration or thrust vector changes.
- **IL.X.B.R6** — Altitude variation/vertical speed.
- **IL.X.B.R7** — Distractions, task prioritization, loss of situational awareness, or disorientation.
- **IL.X.B.R8** — Other hazards specific to the powered-lift make and model.

## Skills elements

- **IL.X.B.S1** — Convert from thrust-borne configuration to wing-borne configuration during straight-and-level flight.
- **IL.X.B.S2** — Convert the aircraft from wing-borne configuration to thrust-borne configuration during straight-and-level flight.
- **IL.X.B.S3** — Utilize proper control technique throughout the maneuver.
- **IL.X.B.S4** — Maintain awareness of aircraft performance, limitations, and relative position throughout the maneuver.
- **IL.X.B.S5** — Maintain altitude ±100 feet and specified heading ±10° throughout the operation. Achieve and maintain targeted airspeed ±10 knots.
- **IL.X.B.S6** — Use single-pilot resource management (SRM) or crew resource management (CRM), as appropriate.
- **IL.X.B.S7** — Use the appropriate checklist, if applicable.
- **IL.X.B.S8** — 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.

## 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.