Garmin's GFC 600H helicopter flight control system is now available in an IFR configuration with a stability augmentation system (SAS). This configuration includes collective control, bringing four-axis capability to the GFC 600H system for the first time. Leonardo Helicopters' AW109 Trekker is the first platform to incorporate the GFC 600H with IFR and collective axis capabilities, providing operators with an advanced flight control solution that reduces pilot workload and improves mission effectiveness.

"We are very excited to now offer a four-axis, IFR flight control system for the helicopter market. This technology will provide IFR operators with advanced automated flight capabilities and bring added protections to one of the most challenging flight categories in aviation. We're confident AW109 Trekker operators will be impressed with the performance of GFC 600H," says Carl Wolf, Garmin vice president of aviation sales and marketing.

The GFC 600H features a console-mounted mode controller with push-button controls and a night vision goggle-compatible display. Digitally controlled, high-performance servos and Garmin-developed linear actuators allow for faster, crisper, more powerful responses, enabling the GFC 600H to perform with smooth handling throughout the flight envelope. Autopilot modes supported include altitude acquire, altitude hold, approach auto-level, radar height hold, as well as vertical speed, indicated airspeed, heading select, attitude hold and more. Using navigation system inputs, GFC 600H can also fly various approach types.

The IFR configuration of the GFC 600H consists of a GMC 605H mode controller, GFS 83 smart servos in each of the four axes and three GLA 85 smart linear actuators (pitch/roll/yaw) resulting in a reliable digital system that is lightweight, yet rich in features. Unlike traditional IFR helicopter flight control systems, the GFC 600H uniquely leverages its smart servos to eliminate the need for dual linear actuators in each axis along with flight control computers, resulting in a digital system that is lightweight and cost-effective while still the providing redundancy required for IFR flight.

The GFC 600H SAS functionality improves the helicopter's basic flying characteristics throughout the flight envelope, as well as enhancing pilot handling and precision. Using the smart linear actuators, the GFC 600H provides rate damping without moving the cyclic, providing a highly capable SAS solution for operators.

In addition to pitch, roll and yaw axis control, the GFC 600H can now control the collective. Power management enables additional functions that can enhance safety and reduce pilot workload. For example, the GFC 600H can allow a pilot to cruise, transition to hover and hover, all completely hands-off. New safety features available with fourth axis include low height protection and power limiting. Low height protection can help prevent controlled descent into terrain by automatically raising the collective to reduce descending vertical speed. Power limiting can keep engine parameters below maximum limits by lowering the collective, in order to prevent engine exceedances.

The new capabilities in the IFR configuration of GFC 600H expand a portfolio of previously certified features in the VFR configuration of GFC 600H available for AS350 and Bell 505 helicopters. Safety tools such as Garmin's Helicopter Electronic Stability and Protection (H-ESP) help the pilot remain within a safe flight envelope when hand-flying the helicopter. A dedicated LVL button can be engaged by the pilot to return to straight-and-level flight, helping to avoid potential disorientation in degraded visual environments (DVE) or inadvertent entry into instrument meteorological conditions (IMC).

The IFR configuration of the GFC 600H flight control system has received EASA approval on the AW109 Trekker helicopter. FAA approval is expected later.