Ultimate Guide: Smart Features of Garmin GFC Autopilots for Aviation
If you have already flown a Garmin GFC-equipped aircraft, you have had the opportunity to experience first-hand the benefits of these digital autopilot systems. They are designed to provide pilots with the tools they need to fly their aircraft with confidence and ease, offering a range of advanced features that make flying safer, more efficient, and more enjoyable. All this while being a cost-effective retrofit autopilot solution with a lower cost of ownership coming from the design of the systems.
The GFC 500 is designed for less complex single-engine piston aircraft, and the GFC 600 is intended for high-performance piston single and multi-engine as well as turbine-powered aircraft. They are attitude-based rather than rate-based (AHRS-based technology). As a standard, the systems have full pitch and roll axis control capabilities (2 axes), with the option of adding a third servo for the yaw axis and even a fourth for the pitch trim. Additionally, installation of the yaw axis option unlocks the Smart Rudder Bias safety feature for GFC 600 in select twin-engine piston aircraft.
In this article, you can take a closer look at some of the essential features of Garmin's autopilot systems, explore how they work and what benefits they can bring to enhance your flying experience.
What Do the Systems Offer?
Electronic Stability and Protection (ESP)
This safety feature will help you avoid uncomfortable and risky in-flight situations. To do so, it provides you with flight envelope protection while hand flying. Although it uses the same control servos as the autopilot, this ESP feature works independently of it to correct for the bank, pitch, and airspeed exceedances. The greater the exceedance, the greater the corrective force.
If you happen to be in such situation where the ESP is active for a predetermined time period (10 seconds), it engages LVL mode during the next 20 seconds with an aural alert "ENGAGING AUTOPILOT" to bring the vertical speed to zero and the wings to level.
Assistance also comes in a visual form. With the compatible display, you can see the 45° bank limiter mark indicating the area in which the servos will be activated to bring the plane back towards level flight. Once at a bank angle of less than 30°, the corrective force deactivates.
Pitching up or down beyond airframe-specific limits is discouraged by the system, too – again with increasing corrective force applied. The ESP also provides high-speed and low-speed protection. If the aircraft is exceeding VNE, the nose is pitched upwards to reduce airspeed. When properly equipped with a valid terrain database, ESP can provide low-speed protection. As the aircraft approaches a stalled condition, the stall is prevented by lowering the nose (this feature is always disabled below 200 feet AGL).
It’s like having an instructor next to you who always nudges you in the correct direction. Of course, there’s an option to disable ESP for those times when you want to go out and practice steep turns or lazy eights.
Stay Within the Speed Limits of Your Aircraft
The systems have Overspeed Protection active when the autopilot is ON and in certain modes while descending if the aircraft exceeds VNE. Let’s say you forget to reduce thrust during the descent – the nose will automatically pitch up, the MAXSPEED message will display, and the vertical mode of the autopilot will change to indicated airspeed (IAS) while changing the previous vertical mode to ARMED (until you correct that overspeed condition and the previous vertical mode becomes active again).
Underspeed Protection is also active when the autopilot is turned on, and it's intended to discourage operation below established speeds in order to avoid a stall. When this happens, a visual alert of MINSPEED displays, the nose is pitched down to increase airspeed, the autopilot’s active vertical mode changes to IAS mode, and when in altitude critical modes, there's an aural alert of "AIRSPEED". When you increase the airspeed, the previous mode becomes active.
You Have Control
Both systems have System Health Monitoring, which is constantly monitoring and comparing values within the system between components. If a fault is sensed, it disengages the autopilot while providing the pilot with visual and auditory alerts.
This function makes sure you are never taken hostage midair by your autopilot and that you are always in control of your aircraft.
Equipped with onboard microprocessors and connected to your aircraft's control surfaces, the Smart Servos are used to apply control inputs as commanded by the autopilot. Digitally controlled speed and torque limits on these inputs allow for a faster, crisper, and more powerful response. For maximum reliability and safety, the servos feature brushless motors and no mechanical slip clutch.
This design result is improved reliability over older solutions, and you pay less for maintenance.
Smart Rudder Bias (GFC 600)
Safety-enhancing technology for select twin-engine piston aircraft brings you another level of comfort and safety. Twin-engine aircraft inherently have aircraft controllability concerns in the event of an engine failure and pilots can expect significant yaw toward the inoperative engine, resulting in an unstable aircraft state.
In addition, due to a sideslip condition and a windmilling propeller, there may be reduced lift on the wing associated with the inoperative engine and simultaneously an increase in drag. All of these factors contribute to degraded performance and a critical loss of airspeed.
When your aircraft reaches the manufacturer's published minimum control speed (VMC) during the takeoff roll, Smart Rudder Bias is automatically armed. Smart Rudder Bias continuously monitors engine parameters using Engine Indication System (EIS) data displayed on a G500 TXi or G600 TXi flight display and activates when the system detects a predetermined power differential between each engine. Once activated, the rudder force is dynamically adjusted to aid you in providing enough force to the rudder to help control a sideslip.
This gives you time to take the proper action required in order to better maintain positive aircraft control and help keep the aircraft in a safe flight condition.
What Do Pilots Say?
Many pilots have praised the autopilot's ability to safely and accurately navigate planes, with some citing its easy-to-use interface and intuitive features. Many pilots have also commented on the autopilot's ability to quickly adjust to changing conditions, such as turbulence and wind gusts, and its ability to recognize terrain and landmarks. Overall, the reports from real use have been overwhelmingly positive.
Become a Safer Pilot
Garmin autopilots are a cost-effective retrofit solution. They offer a lower cost of ownership, provide a precise and smooth flying experience, and offer safety features you simply won't find elsewhere, especially in a retrofit autopilot system.
Are you interested in upgrading your flying experience with Garmin GFC digital autopilot system? Contact us to get more info about the installation options.