The Road to Certification: GFC 500 for the Retractable 182s

Garmin’s GFC 500 autopilot is still very new, and supported aircraft are being added all the time. TROY WHISTMAN, a Cessna Flyer Association member, was selected and agreed to loan his 1980 Cessna TR182 Turbo Skylane RG as a test aircraft for Garmin’s certification of the autopilot in retractable Skylanes. Here is his story, including tips for how you might improve the chances of your aircraft being selected, too.

The morning of Monday, July 15, 2019, dawned over Olathe, Kansas, with a beautiful sunrise, as I awoke with a burst of excitement. Today, with any luck, I’d be picking up and flying home our 1980 Cessna TR182 Turbo Skylane RG with a newly installed 3-axis GFC 500 digital autopilot. 

Exactly 116 days (almost four months) earlier, on March 21, I had flown our airplane from the Dallas area to New Century AirCenter Airport (KIXD) in Olathe, Kansas, home of Garmin’s Flight Test group. I left the TR182 in their care while they used the airframe as a certification test vehicle to make the autopilot available for all retractable Cessna 182s. This story covers that journey.

A game-changing autopilot 

Like many who fly older Cessna aircraft, my 39-year-old airframe was equipped with a Cessna Nav-o-Matic single-axis autopilot—the 300A, to be exact. While it held course/heading just fine, it couldn’t fly a glideslope, handle vertical descents, or capture (much less hold) an altitude during cruise flight. 

One might argue that Cessna 182s are stable aircraft, and you really don’t need an autopilot to hold altitude when properly trimmed. In fact, I made that same argument to my friends for several years as I flew single-pilot IFR in this excellent airframe.

Then, Garmin announced the GFC 500. 

I looked at the feature list: IAS mode climbs (often called FLC, for “flight level change”); VNAV capabilities to automate step-downs on approaches and arrival procedures; full GPSS capability for holding patterns, entries, and turn anticipation; ILS/LOC/BC/VOR/GPS/RNAV approach capabilities; envelope protection; and the LVL button. This thing had it all. 

While I wanted one installed yesterday, Garmin certifies these units by make and model. When the Cessna 182 was finally announced as ready and available, I tried to make the case with them that the R182 and TR182 were covered by the same 3A13 Type Certificate Data Sheet, and thus the R182/TR182 should be covered by their standard Cessna 182 certification work, to no avail. 

Due to the CG shift with the gear in transit, the Lycoming versus Continental powerplant, and the higher service ceiling, the TR182 would need to be certified under its own program of test flights.

Like many of you who are interested in the GFC 500 program, I religiously followed Garmin’s Supported Aircraft matrix showing which aircraft are currently covered by STC, which aircraft they are currently working on certifying, and which programs they plan to begin in the next 12 months. I also filled out Garmin’s online form expressing my interest in seeing the TR182 certified. (The links to a list of supported aircraft and Garmin’s request form for additional models can be found in Resources. —Ed.) 

Not to be deterred, I emailed way back in July 2017 to log my interest and received the same default message that many of you have received:

 “Thank you for reaching out. Your request has been received and we will use this information to evaluate the marketplace for future certification efforts.”


Improving my odds

I had no idea what criteria Garmin uses to select certification program candidates, but I knew my name was in the hat because I filled out the form. (NOTE: There is a separate form to complete if you’re interested in allowing Garmin to use your aircraft to certify their GFC 500 or 600 autopilot, versus just interested in buying one when it’s ready. See Resources. —Ed.)

However, I did know that the GFC 500 requires a Garmin G5 to be installed, as the G5 has the “brains” of the autopilot. So, in the winter of 2018, I undertook a panel renovation with the help of a good friend, supervision by an A&P/IA, and advice from a booked-through-2020 avionics shop owner. 

We did the work ourselves, gutting the old 1980s plastic panel and associated wiring, and over the course of two months transformed the airplane with a laser-cut flat metal panel with laser-etched labels (see sidebar at right), new glareshield and instrument lighting, dual recessed G5s, flush-mount JPI 830, custom warning LEDs for alert conditions and a new avionics electrical panel with extended main bus. 

Through our avionics contact, we obtained the wiring diagram for the GFC 500 install and pre-wired the airplane for the GMC 507 (that’s the GFC 500’s control head in the radio stack; the box with the blue LVL button), breakers for the autopilot servos, dual inputs to the audio panel for autopilot alert tones, yoke wiring for the trim switches and disconnect switch and more. 

The plan: get the airplane as close to “ready” as it could be, with the goal of improving our odds of being selected by minimizing the work Garmin would have to do if we were selected. 


Getting lucky

From the moment the program had been launched, I used web monitoring tools to let me know the instant any change was made to the “available/working on it/coming soon” list on Garmin’s website. 

When I’d see that a new plane was available, even though it wasn’t the R182/TR182, I’d often post a positive message to the North Texas Aviators Facebook group, alerting others that flew whatever newly certified type was just announced. One member who flew the Grumman Tiger got his Garmin autopilot installed just after it was certified. I drooled over his installation for some time. 

Then, one day in February 2019, after posting yet another “not for my R182/TR182 but YOUR aircraft type is now available” message on Facebook, I received a private message from someone who happened to be a North Texas representative of Garmin that had seen my posts. 

He and I spoke over the phone, and then he made an email introduction to the certification team at Garmin about me and my plane. I never got a reply from that team… it was as if the email went into a black hole.

Later, I discovered they weren’t being rude but rather, were and are laser-focused on the projects they’re currently certifying. They simply file away incoming emails/requests for future reference.

Once I completed the panel upgrade project. I sent the Garmin team another email, with pictures of the work we’d done and all the pre-wiring that was in place. Still, crickets.

In mid-March, out of the blue, while working from my home office, my cellphone rang. The caller ID showed the number was from Olathe, Kansas, and my heart skipped a beat. Could it be?

I answered the phone and on the other end of the line was the lead Garmin Autopilot Certification Program manager. He told me that they’d reviewed the list of eligible aircraft for the R182/TR182 certification program and were ready to begin that project. Would I still be interested in letting them use my airplane?


I answered without hesitation.

I learned it would take about 10 weeks and that the autopilot and installation would be at no cost to me in exchange for allowing them to use the airframe. That sounded like a swell deal to me!

In the two weeks between that call and delivering the airplane to Garmin, there was a flurry of activity: legal forms needed to be reviewed and completed, allowing Garmin to use the airplane and defining what each of us was responsible for, discussion of liability, insurance coverage and so on. 

I utilized my AOPA Legal Services Plan to have the contract reviewed before I signed it. Garmin then sent one of their A&P/IAs to Texas to do a thorough pre-acceptance inspection. He checked logbooks, annuals and conducted a thorough review of the airframe. 

And when I say thorough, I mean thorough. He didn’t find much wrong with this well-maintained airplane but did note, for example, that “the washers on the bolts securing the rear bench seat to the floor might not be the correct ones.” Did I mention he was thorough?  

Garmin expected the certification effort to take about 10 weeks, until about June 6, 2019, so they verify before accepting your airframe that its annual won’t expire in the middle of their work. My annual was set to expire June 30, so we were good to go.

That’s how it came to be that on March 21, 2019, I flew our airplane to Olathe, Kansas, and flew home commercially.

For the next four months, I followed flight test progress on FlightRadar24 and FlightAware; and eagerly consumed email updates with pictures sent by the team at Garmin. 

At one point, test flights were suspended for a couple of weeks due to a servo failure during heavy ground tests. The GFC 500 is so popular in the market, however, that it took Garmin themselves a couple of weeks to get a replacement. 

As it turned out, they were right and I was wrong—the 3A13 TCDS, which covers all the 182 series, wouldn’t have been enough to certify the TR182, which flies as high as FL200. The air is so thin that high that control pressures become exceedingly light. 

Garmin had to have the G5 team make software changes to the gain range for the GFC 500, which allowed them to configure it to work as it should at the TR182’s service ceiling. That software change happened quickly, demonstrating the responsiveness of this great team of individuals.

I was pleasantly surprised that they equipped my airplane with the yaw damper feature. It’s optional when you buy the autopilot, but they can’t sell it if they haven’t certified it for your make and model. So, when your airplane is selected for the STC program, you end up with a yaw damper. “Oh, well, if you insist!”

My airplane didn’t come with electric elevator trim when it left the factory, but it has it now, thanks to the automatic electric trim installation Garmin added. All told, I received a modern 3-axis digital autopilot with four servos: yaw, pitch, roll, and automatic electric pitch trim.

“It’s done!”

While it seemed like forever being without my airplane, the day finally came when Garmin called to say, 

“It’s DONE!”

And that’s how I came to be standing in the hangars of Garmin’s Test Flight Center doing final inspections and picking up my airplane. I arrived at 8 a.m. and brought doughnuts as a thank you for the team. 

The install was completed, but the final FAA paperwork and STC were still in progress. I wondered if I’d get out Monday or would need to wait until Tuesday. While all the paperwork was being done, Garmin dedicated a shop crew to washing and detailing the plane, even using leather cleaner on the interior. 

The certification team worked hard and got all paperwork finished by early afternoon. I signed paperwork and they turned the airplane back over to me. The plane was returned better than I left it: clean, with a full tank of 100LL, and I enjoyed a relaxing IFR flight home with the new autopilot guiding the way. 

It locked onto altitudes, headings and nav courses like it was on rails, and handled updrafts and downdrafts without wavering or disconnecting. I’m very pleased with the outcome.

Afterward, as I was looking through the logbook entries, I stumbled on another surprise. While Garmin was in possession of the aircraft, they had discovered that the wet wing’s fuel tank top access plates wept a bit when the tanks were completely full. 

I had never discovered this as I typically run the tanks at the tabs (65 gallons) for more useful load. During the time the plane was waiting for the failed servo replacement, Garmin drained the tanks, removed and then resealed those covers. 

The story: Garmin takes care of you. They are great people at a great company. While I felt they were doing me a favor by “giving me a free autopilot,” their behavior was as if I were doing them a favor by letting them use my airplane.

How do YOU get selected?

I don’t have any magic answers. There’s a bit of luck in this. But I will share something the program manager told me as I picked up the plane. 

When it comes time to make the selection, Garmin staffers sift through many online submissions and paper interest forms filled out at Oshkosh and other events. 

On a recent project startup (not mine), while looking through the paper forms submitted at EAA AirVenture Oshkosh, one had “YES! YES! YES!! PLEASE PICK ME!!!” written in big bold capital letters at the bottom where this question was asked: “Would you consider letting us use your airframe to certify the autopilot?” 

Any idea who got picked? 

You guessed it. 

If your airplane is as close to stock (conforming with the original type certificate) as possible, that improves your odds of selection. If you have STCs that alter flying characteristics significantly such as vortex generators, a STOL kit, and/or engine/prop upgrades, that may reduce your chances.

My odds were slightly improved by having the turbo example of the R182/TR182 series, due to filter-down effect. If Garmin certified the autopilot for the TR182, it would also apply to the R182, but the reverse was not true.

So, my advice to those who want to be selected is to show some public enthusiasm for the product, go where you might meet Garmin people, be genuine and shake some hands. As with many things in life, it’s not what you know, it’s who you meet and how you interact with them that influences opportunities that come your way. 


That’s my story! I hope you get to experience flying your plane with the awesome GFC 500 soon, whether you get it for free or pay to have it installed.

In closing, I must say “Thank you!” to the entire team at Garmin for a positive experience and a fantastic autopilot.


Troy Whistman is the father of three grown daughters and has been married 30 years to his lovely redhead bride, affectionately called “Lady Red.” Together, they base their airplane at the Mid-Way Regional Airport (KJWY) south of Dallas, Texas. Whistman holds a commercial airplane SEL certificate with instrument airplane rating. When not flying for fun to catch a sunrise or sunset, he enjoys using his toys as tools to help others: he flies for and is on the board of directors for Angel Flight South Central, and thinks flying kids for Challenge Air is some of the most rewarding flying he does. Send questions or comments to .



Cessna Flyer Supporter

Garmin Ltd. 
Supported Aircraft List (GFC 500)
Autopilot Interest Form (GFC 500/600)
Autopilot Certification Aircraft Loan Form (GFC 500/600)
Resources: Other