AutoPilot Modes & Features

This section provides a brief overview of the AutoPilot’s capabilities. More detailed descriptions and the operating procedures will be provided in the Pilot’s Flight Manual Supplement and upon request. For more information contact us at [email protected] or 1.204.318.7544.


Aircraft Stability Modes

The basic stability modes are available for use from liftoff to landing. They provide a high level of aircraft stability, both transparent and visible, to the pilot. These modes provide a much more stable aircraft and allow a much lower pilot workload while increasing the ability for precise maneuvering.

The stability Augmentation is performed through dedicated in-line actuators whose high speed, high bandwidth and high accuracy provide rapid and precise reactions to any instability and perturbation including wind gusts, rough air and turbulence. The unrivaled responsiveness of the stability augmentation system contributes to an unmatched ride quality for pilots and passengers

ATRM mode provides basic heading hold and turn coordination on the yaw axis. When below 50kts, or when the roll angle is less than 4 degrees, the AutoPilot will utilize yaw inputs to maintain the heading. When the roll angle exceeds 4 degrees above 50kts the AutoPilot will automatically control pedal position as required to maintain coordinated flight. This allows the pilot to easily perform coordinated turns with simple cyclic inputs while keeping their feet on the floor. Additionally, the manual pedal input normally required with large collective changes is managed automatically by the ATRM function.


Basic AutoPilot Modes

The basic flight director AutoPilot modes are available to the pilot to allow true hands-off flight. The modes may be combined such as engaging Heading, Altitude, and Airspeed holding simultaneously or individually as the pilot may desire.

The heading mode enables the AutoPilot to select, capture and track a desired aircraft heading. The heading hold mode is engaged by pressing the HDG button on the control panel. When the mode is engaged, the aircraft will turn to and follow the HSI heading bug.

The IAS mode enables the AutoPilot to capture, maintain and adjust a desired indicated airspeed. The pilot may adjust the speed target by pressing the forward or aft cyclic beep trim switch and releasing when the new desired speed is attained. Should the current airspeed lie outside of the normal operating envelope the AutoPilot will bring the new target back into limits

The ALT mode enables the AutoPilot to capture, maintain and adjust a desired barometric altitude. The pilot may adjust the altitude target by pressing the beep trim switch and releasing when the new desired altitude is attained or using the collective Force Trim Release button for larger changes of the altitude reference.

The VS mode enables the AutoPilot to capture, maintain, and adjust a desired rate of climb or descent speed. The pilot may adjust the vertical speed target by holding the beep trim switch and releasing when the new desired vertical speed is attained or by using the force trim release switch for larger changes.

The RHT mode enables the AutoPilot to capture, maintain, and adjust a desired Radio Altimeter height. The pilot may adjust the height target by pressing the collective beep trim switch or holding the collective force trim switch and releasing when the desired height is attained. The RHT mode is performed by AutoPilot inputs on the collective axis control and may be simultaneously engaged with pitch and roll modes.

The Hover mode enables the AutoPilot to capture, maintain, and adjust a desired ground referenced velocity or a stationary position. When a stationary hover is commanded, the AutoPilot will make the corrections necessary to hold the position regardless of changes in wind speed and direction. The heading of the helicopter will be held automatically and can be adjusted by providing pedal inputs or inputs on the collective beeper.

The Go Around mode enables the AutoPilot to perform a fully hands off wings-level climb at the best rate of climb speed with a single button push. The mode is available for use when airspeed is greate than 50kts. It may be used to terminate an approach procedure, during a departure, or any time the pilot desires to automatically transition to a Vy wings level climb, such as recovery from spatial disorientation or inadvertent IMC encounter. The GA mode is performed by AutoPilot inputs on the pitch, roll, yaw, and collective controls.

The departure mode enables the AutoPilot to perform a straight, steady acceleration and climb from low speed (<50kt) and hover flight conditions with a single button push. This mode is very valuable for automatic recovery from inadvertent loss of visual reference conditions such as white-out and brown-out in hover. It is activated using the same button as Go Around.


Navigation (NAV) Modes

This mode provides capture and tracking of the lateral guidance from a GPS/FMS system that is selected as the navigation source by the avionics system. This mode is used to provide a full hands-off following of any route defined in the FMS/GPS.


Approach Modes

The AutoPilot provides full hands-off guidance on Localizer, ILS, LP, and LPV approaches. Both the lateral and vertical guidance will be tracked down the approach. When the GS mode is engaged and a valid RadAlt signal is available, the AutoPilot will perform an automatic level off at 50 feet height and continue flying down the runway centerline. Automatic tracking of the approach centerline is performed with roll control inputs, and the glideslope is tracked with inputs to the collective axis. The airspeed hold mode (IAS) may also be engaged during these approaches for a fully hands-off automatic approach to the runway.

When the AutoPilot is engaged in APPR & GS modes on an ILS or LPV approach and the DCEL mode is armed, it will automatically engage during the approach profile to provide a smooth deceleration from any initial approach speed to 70KIAS at approximately 200ft AGL (for ILS) or 300ft AGL (for LPV). The pilot may use the airspeed hold (IAS) mode to fly the initial portion of the approach, then let the AutoPilot automatically engage DECEL and perform a comfortable deceleration to the approach minimums altitude.

The AutoPilot is able to perform a fully hands-off approach from initial approach conditions to a stationary hover at specific RadAlt height. The ATH mode is intended to provide an automatic, hands-off, predictable profile descent & deceleration to hover. The ATH mode is based on a capture and hold a line principle so that the aircraft decelerates in level flight (if necessary, to join the descent profile) and then descends & decelerates using a constant slope relative to the ground. This constant angle approach enables the pilot to easily predict the final hover point. Once the hover targets are reached, the HOV & RHT modes are automatically engaged allowing for a fully hands-off hover. At the end of the description add: The pilot can adjust the descent slope and heading with the collective beep trim switch to precisely direct the aircraft to the desired hover point.


Other Protection Modes

When coupled, the system can automatically limit upward collective movement to ensure engine power limits are not exceeded, or to automatically limit downward collective movement to prevent the helicopter from entering autorotation and high rotor RPM.

The TAWS mode reduces CFIT hazards by automatically commanding an avoidance maneuver upon receipt of an alert from a separately installed Terrain Warning System and when no evasive action is performed by the pilot. TAWS mode is available while the helicopter is in cruise conditions.


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