Garmin Autoland/Autothrottle: Enhancing Safety While Reducing Workload

Upgrading aircraft, especially avionics and automation, enables owners to reinvest in an aircraft that may already be fully depreciated rather than purchasing new or late-model aircraft for significantly more money—if you can afford the downtime.

Earlier this year, FLYING provided an in-depth look at the new Beechcraft King Air Garmin Autoland. The industry waited a long time to have the ability for a GA aircraft to land itself, but it’s here now and it was worth the wait because it’s so much more.

Autothrottles will help reduce pilot workload, improve fuel economy, and provide a level of safety protection in situations such as underspeed, overtorque, or even when an engine fails. The fact that some of the autothrottle safety features engage when one engine is inoperative may be all the sales pitch needed to get this valuable upgrade.

For example, loss of one engine will direct Garmin’s electronic stability and protection (ESP) system to limit pitch and roll inputs while hand-flying. ESP limits the roll to 10 degrees on the failed engine side and 40 degrees on the other. A visual indication of these limits automatically appears on the PDF. Pitch limits are also set at 10 degrees nose up and 5 degrees nose down. It also keeps the aircraft 15 knots above VMCA.

That is not to say the pilot cannot bank or pitch beyond those limits—it just means there is envelope protection in the form of heavier control forces to overcome to exceed those limits manually. Think of this as a lane departure warning in a vehicle—you can still change lanes; you just get sensory feedback that demands your attention.

However, if any of the limits are exceeded for a prolonged period, the autopilot reverts to wings level. If no pilot intervention happens within two minutes, the autoland feature is triggered and a computing process begins to determine the safest place to land based on parameters including fuel, terrain, weather, airport environment, and more, and then the aircraft flies itself there to land while communicating with ATC and passengers.

Garmin now offers autoland/autothrottle functionality for the iconic King Air if you happen to own one that meets specific parameters:

• King Air 200/B200 model

• Pratt & Whitney PT6A-42, -52, or -61 engines

• Four- or five-bladed propellers

• Hydraulic landing gear 

• Garmin G1000 NXi Flight Deck

That last bullet requires a bit more explanation. If your King Air is an older configuration with an analog panel or the basic G1000, that system must be upgraded to an updated NXi to be eligible for the STC.

The King Air is a popular corporate aircraft, given its wonderful performance and operating cost making it a versatile platform—but it can be labor intensive to fly.

In a series of instructional videos, Garmin demonstrates the use, benefits, and effectiveness of the new King Air autoland/autothrottle to reduce pilot workload and give passengers peace of mind. Unlike larger corporate aircraft that might have a cockpit door or more space between crew and passengers, there are no secrets in a King Air. If something goes wrong up front, everyone in the cabin will know about it.

Garmin’s autoland system helps keep everyone informed and as calm as can be expected if, for example, the pilot becomes incapacitated.

​​Garmin’s autothrottle reduces workload by managing power levels and can even show mode annunciations and airspeed targets on the flight display.

The system is engineered to help manage the flight path, focusing on vertical path speed and energy control. It operates the power levers across their entire range, from idle to maximum power, and is usable throughout all phases of flight—from the takeoff roll to the landing rollout. 

Garmin autothrottle sets and holds power levels based on manufacturer recommendations or user-configured climb, cruise, and descent schedules, including key engine parameters such as interstage turbine temperature limits. Autothrottle also brings added protections by automatically reducing power if the system senses an over-temp/overtorque of the engines, or in the event of a flap, overspeed.

In an under-speed condition, the autothrottle will automatically engage and add power to get the aircraft back toward an optimum state of flight of 15 knots above VMCA. Garmin autothrottle can also aid the pilot during an engine failure.

The autothrottle reduces pilot workload, freeing up mental resources for managing active threats while minimizing opportunities for error. It also allows pilots to conduct procedures more precisely during routine and abnormal situations, enhancing operational effectiveness and likely improving fuel economy by automatically adjusting power to match flight conditions.

This system is priceless when the pilot or crew must maintain control of the aircraft while performing non-normal checklist tasks. The Garmin autothrottle greatly eases the pilot’s workload during a go-around in a King Air, one of the highest workload phases of flight, especially in single-pilot operations or challenging IFR conditions. 

The autoland feature for King Air (and other GA aircraft with the feature) is quite different from an autoland feature in a commercial airliner.

While many commercial aircraft use autoland systems coupled with instrument landing procedures routinely to assist the crew in safe, smooth landings to minimums, the Garmin feature is for emergency use only. Whereas autothrottles are designed to assist the pilot and reduce workload, autoland is a safety feature of last resort—like pilot incapacitation.

As mentioned earlier, when autoland is activated, it selects the best airport and runway, considering factors such as fuel level, weather, runway dimensions, terrain, and obstacles. But it also handles ATC communications and begins squawking 7700—the universal emergency code—from the transponder to signal that immediate assistance is required.

Additionally, Garmin Autoland provides clear visual cues to passengers, informing them of the airport where the aircraft will land.

Garmin’s King Air solutions web page offers a glimpse of its offerings for the legendary platform, each designed to reduce workload and reaffirm crew confidence. 

To start at the beginning, the FAA defines an STC as a type certificate (TC) issued when an applicant has received agency approval to modify an aeronautical product from its original design. The STC, which incorporates by reference the related TC, approves not only the modification but also how it affects the original design.

The STC identifier covering this upgrade is SA01535WI-D. Garmin provided the following detail on the autoland/autothrottle STC for King Air 200 operators who wish to upgrade their analog instrumentation to an all-digital Garmin G1000 NXi avionics suite with this STC.

In July 2023, the G1000 STC was updated to include options for Garmin Autothrottle and Autoland and new G1000 NXi features.

Full autothrottle integration with the G1000 NXi reduces crew workload in the cockpit by managing aircraft speed and power, and provides engine protection against potential engine exceedances. In an emergency where the crew can no longer perform its duties, Garmin autoland can control and land the aircraft without human intervention.

The G1000 NXi-integrated flight deck in the King Air also includes a new GFC 700 digital autopilot, new weather radar, synthetic vision, and more—all of which is needed for the autoland system to function properly.

An avionics upgrade of this scale is a major maintenance event. Eric Smith, MRO technical sales manager for Banyan Air Service in Fort Lauderdale, Florida, explained how he works with clients to ensure a smooth maintenance visit.

“In today’s information-rich world, customers often clearly know what they’re looking for before reaching out,” Smith said. “After our initial conversation, I gain a thorough understanding of their objectives. Using the tail number, serial number, equipment list, and a cockpit picture, I guide them toward the systems that best match their aircraft and mission requirements, including options they may not have considered.

“I’ll outline the essential components needed for the installation and equipment and recommend additional options that could enhance their setup, though they are unnecessary. Following our discussion, I’ll research the relevant STCs for the equipment, airframe, and serial number range.

“Once I’ve prepared the quote, it undergoes an internal review to ensure all necessary parts and DERs [designated engineering representatives] are included and everything integrates seamlessly. After making any necessary adjustments, I send the finalized quote to the customer and arrange a follow-up conversation to review the proposed package. I’ll also check if any maintenance is required during the installation process.”

Each shop has its nuances, but the business of aircraft maintenance is relatively universal. The deal begins with an initial scope of work, followed by a maintenance action plan (MAP), implementation, testing, and return to service. Other work desired by the owner, including unrelated squawks, upgrades, and manufacturer’s recommended service advisories to be completed while the aircraft is in for service, need to be agreed upon beforehand.

There may also be compatibility issues with other equipment installed in the aircraft that also may have been done via STC.

“Quoting an STC can be very tricky, especially for a larger complex aircraft,” said Kirk Fryar, vice president and owner of Sarasota Avionics & Maintenance in Venice, Florida. “There are many variables to consider.”

Once the scope of work and compatibility issues are resolved, the fun begins.

Maintainers develop a plan and map out the installation beginning with guidance for Garmin about install requirements.

King Air 200/B200 Garmin Autothrottle and Autoland STC require Garmin’s G1000 NXi-integrated flight deck with Phase 2 hardware on models powered by Pratt & Whitney PT6A- 42, -52, or -61 engines with four- or five-bladed props. GSA 87 servos for the autothrottle and autoland are also required. Additionally, the aircraft must be equipped with PT6A-42, -52, or -61 engines and four- or five-bladed props. 

Avionics upgrades are potentially fraught with pitfalls, and success requires extreme attention to detail.

“Upon the aircraft’s arrival, we conduct a comprehensive inspection, including checks of all avionics systems and the interior,” Smith said. “We document our findings, take photographs, and send them to the customer. We also ensure the aircraft is fully protected in our care and custody. We then inform the customer of any issues we’ve identified and offer the option to address these repairs during the installation.

“Once the initial inspection and documentation are completed, we remove and protect the aircraft’s interior, which is then moved to secure storage to prevent any damage. Next, we access and remove the parts and panels required for the installation.

“Our installation supervisor, lead technician, and engineer have reviewed the STC instructions and held a meeting to plan the necessary tasks. We have often prefabricated some of the wire harnesses to streamline the process. Once access is fully gained, we can commence the installation.”

Like most upgrades at home or hangar, things are going to look bad before they get better. A major upgrade like autoland/autothrottle is going to require access throughout the airframe, exposing all manner of wiring, rigging, and equipment. It might be best if the customer doesn’t visit to check on progress. Regardless, the end result will be worth the downtime.

With the installation complete—and before the aircraft is reassembled—exhaustive testing and checking of each wire, pinning, and splicing occurs. This would be followed by power and ground checks to verify the correct voltage levels.

Once these steps are complete and an inspector has approved, reassembly begins. Then another inspection ensures the systems are working correctly and everything is properly closed and installed.

Upon final completion, the pilot meets with the installation team to review the system’s operation and ensure they are entirely comfortable before taking the aircraft for a test flight.

FAA Order 8110.54A-Instructions for Continued Airworthiness Responsibilities, Requirements, and Contents states the purpose of ICAs in Chapter 2, Section 2: “The purpose of the ICA is to keep products airworthy. The ICA documents recommended methods, inspections, processes, and procedures. The ICA must contain information on each item or part, as appropriate, installed on the product.”

Operators who choose to equip their King Air with Garmin Autothrottle and Autoland will receive a document ensuring proper maintenance and checks. Continued airworthiness instructions are also provided to the authorized Garmin dealers performing the installation. This document outlines maintenance procedures for autothrottle and autoland and other maintenance procedures associated with the G1000 NXi. The STC documentation and the ICA provide checks to ensure proper operations.

Another consideration is the aircraft flight manual supplements (AFMS), which document additions to the aircraft flight manual (AFM). This record covers equipment or data added to the aircraft after initial delivery, such as the Garmin Autothrottle/Autoland STC. Inserted into the back of the AFM, the supplement details operation, limitations, and emergency procedures.

Once the aircraft is returned to service, it’s always wise to test the systems in fair weather repeatedly so there are no surprises and it performs exactly as you expect in conditions less than ceiling and visibility unlimited. 

This feature first appeared in the December Issue 953 of the FLYING print edition.