CH.VIII.E — Vortex Ring State (VRS)

CH.VIII.E for the Commercial Pilot Rotorcraft ACS: official objective, references, and 18 exact knowledge, risk-management, and skill descriptions.

FAA-S-ACS-16, November 2023. This study page does not replace the current FAA publication or an examiner's plan of action.

Official task context

CH.VIII.E official ACS context
Certificate or ratingCommercial Pilot
Aircraft categoryRotorcraft
Area of operationArea of Operation VIII. Emergency Operations
TaskTask E. Vortex Ring State (VRS)
Task code prefixCH.VIII.E
Official referencesFAA-H-8083-2, FAA-H-8083-21, FAA-H-8083-25; POH/RFM
FAA documentFAA-S-ACS-16 — Commercial Pilot for Rotorcraft Category Helicopter Rating Airman Certification Standards
FAA source libraryOpen the official ACS library

Official task objective

To determine the applicant exhibits satisfactory knowledge, risk management, and skills associated with main rotor Vortex Ring State (VRS).

What the ACS code means

  • CH identifies the ACS standard family used for this Commercial Pilot Rotorcraft document.
  • VIII identifies Emergency Operations, the Area of Operation.
  • E identifies Vortex Ring State (VRS), 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
CH.VIII.E.K1Elements of vortex ring state.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
CH.VIII.E.K2Effects of wind, weight, temperature, and density altitude.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
CH.VIII.E.K3Requirements for the formation of VRS.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
CH.VIII.E.K4Aerodynamics and indications of VRS.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
CH.VIII.E.K5Flight scenarios under which VRS can occur.Explain the element, apply it to a scenario, and connect the answer to current references or aircraft information when relevant.
CH.VIII.E.K6Effective recovery techniques.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
CH.VIII.E.R1Pilot recognition and response to VRS.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
CH.VIII.E.R2Entering the maneuver at a lower altitude than planned.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
CH.VIII.E.R3Application of power or exceeding powerplant limitations.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
CH.VIII.E.R4Collision hazards.Work through a scenario by identifying the hazard, evaluating the risk, and explaining a practical mitigation or decision.
CH.VIII.E.R5Distractions, 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.
CH.VIII.E.R6Loss of tail rotor effectiveness (LTE).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
CH.VIII.E.S1Complete the appropriate checklist(s).Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
CH.VIII.E.S2Clear 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.
CH.VIII.E.S3Select an altitude that allows recovery to be completed no lower than 1,000 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.
CH.VIII.E.S4Establish conditions leading to VRS entry.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
CH.VIII.E.S5Promptly recognize, announce, and recover at the first indication of VRS.Describe the procedure, interpretation, or decision process that can be discussed during an oral. Physical aircraft performance remains part of the practical test.
CH.VIII.E.S6Use 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.

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 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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