by Michael J. “Mick” Kaufman
© Copyright 2023. All rights reserved!
Published in Midwest Flyer Magazine December 2023 Digital Issue
It has been a busy summer flight training and finishing up three new instrument-rated pilots. Congratulations to Andrew Marso of Franklin, Wisconsin; Eli Judge of Whitefish, Montana; and Kevin Ermis of Conover, Wisconsin. I have two more students to finish yet this year. Along with the instrument ratings, there were numerous flight reviews and instrument proficiency checks, and several BPT flight clinics. During this training, I also learned a lot, especially, about using the latest state-of-the-art avionics, which is the center topic of this issue’s column.
It seems like it would take an entire volume of encyclopedias to document all the different combinations of avionics, which I have seen in the last several decades, so I will highlight one of my most recent encounters. I have addressed this topic before, and I will mention it again. If you have avionics in your airplane that are modern enough to handle WAAS GPS approaches and it works well, don’t upgrade!!!!!! I am talking about the Garmin 430/530 generation of avionics. In evaluating real-world IFR flying in this generation of avionics, there are only two practical applications in these boxes, which I consider missing… the capability to insert airways into your flight plan and the capability to create nonpublished holds when assigned by ATC. Everything else is just fluff.
Sadly, there are aircraft owners whose airplanes have been sitting in a shop for as long as two years trying to get avionics installed and working properly. As for glass displays, they are cool and work well if the pilot does not clutter the display with too much information. Real pilots fly steam gauges, tailwheel airplanes and gliders. As for touchscreen displays, they are great and easy to program in smooth air, but it is different to try and program one in heavy turbulence.
Now for the other side of me, I am a geek and I enjoy the challenge of helping pilots learn what their avionics package can do. One day we spent over 1.5 AMUs (aviation monetary units) or $1,500.00 in fuel to find out why sometimes the autopilot captured the glideslope and sometimes, it did not. It would be too lengthy in this column to discuss every incident I have experienced. Over the years, I have helped many pilots who read my column, troubleshoot their avionics, so if you have an issue, please let me know. Once I had a call from a pilot in Argentina who read one of my articles in Midwest Flyer Magazine, and we were able to help him solve his avionics problem. Proof positive that this magazine’s new “digital” format is now able to reach a lot of people who were not previously reached with its original print format.
For this issue, I have picked a recent training situation I encountered while flying with a pilot at the Fresno, California BPT Flight Clinic, which I am presenting as follows:
Aircraft = V-tail Bonanza.
Avionics = the following:
(1) Garmin GTN-750 GPS Navigator
(2) Garmin G-3X Display
(3) Garmin GFC-500 Autopilot with Garmin ESP-X and air data computer.
Using the above avionics, we were able to determine that some flight features have changed dramatically with this combination of equipment due to envelope protection with the Garmin autopilot, which Garmin refers to as “ESP-X.” In previous installations, if the approach could not be completed and the pilot decided to do a missed approach, he/she followed this procedure: Power UP, Pitch UP, Gear UP while pushing the GO-AROUND button. The flight director gave the pilot a pitch command of about 7 degrees (Bonanza) and disconnected all the autopilot functions, except the flight director command bars. The pilot was now hand flying the flight director command bars in pitch mode. If this approach was other than a GPS approach, the pilot needed to select GPS mode on the navigator, re-engage the autopilot, select the NAV mode, and turn the autopilot back on. If the aircraft was equipped with GPS steering, it was selected instead of the NAV mode for more accurate tracking of the missed approach course.
One last step was necessary after flying the first part of the missed approach… that was to unsuspend the navigator to proceed to the missed approach/holding fix. The reason for disconnecting the autopilot functions on the missed approach was to keep the aircraft from stalling on the climb-out if the pilot should fail to power up and clean up the aircraft.
So, what did our aircraft do in a similar situation with the above Garmin equipment? On the missed approach as the pilot pushed the “Go-Around Button,” the navigator switched to GPS mode for the-3X missed approach, the flight director pitched up, the autopilot went to roll mode, the servos stayed engaged, and the autopilot stayed on. The pilot needed to engage the NAV function on the autopilot and unsuspend the navigator to fly the published missed approach.
In the situation with our training, the missed approach was complex with several turns as the aircraft reached certain altitudes, finally leveling off at the altitude, which we set in the preselect window, all provided by an air data computer. The envelope protection Garmin ESP-X protected the aircraft from a stall in the case the pilot did not apply power and clean up the aircraft.
While training this pilot, I found several items I would consider a firmware glitch that pilots should be aware of with this or similar equipment.
During the ILS approach with GPS assist, the autopilot would disconnect when switching from GPS to VLOC mode and the aircraft appeared to go into autopilot roll mode. This was the normal procedure if you had a legacy King KFC 225 autopilot connected to a Garmin 430/530 navigator, and it was necessary to reengage the approach mode on the autopilot and it caught many pilots off guard.
Another glitch we found was that the vertical NAV function did not work on ILS approaches but did on GPS approaches. We did not have a chance to further test this function by using the NAV mode instead of the approach mode on the autopilot.
It is sometimes difficult to work through items that do not do what is expected when flying different avionics. For what happens with a Garmin GI-275, does not happen on a Garmin G3X or different firmware in any of the other boxes.
I found flying the Garmin GFC 500 autopilot with envelope protection a great experience and would like to share some more of its features.
The Garmin GFC 500 with ESP-X goes beyond providing pitch-and-bank envelope protection to also offer high and low-airspeed protection. In a high-airspeed situation while hand-flying the aircraft, ESP-X engages the autopilot servos to increase your pitch attitude, while built-in parameters further prevent the aircraft from exceeding G-limit load factors. In low-airspeed situations while hand-flying the aircraft, ESP-X engages to provide a gentle pitch-down force to reduce the likelihood of a stall. Both over-speed and under-speed protection also work while the autopilot is engaged should an aircraft performance limitation be reached from a pilot-provided autopilot command.
For example, if the pilot sets an aggressive climb, the aircraft cannot perform, and under-speed protection will limit the pitch attitude to help prevent a stall from occurring. In addition, pitch, roll and airspeed envelope protection parameters are all customizable, and for flight training or aerobatics, you can easily inhibit ESP-X within the automatic flight control system menu of G3X Touch, or with an optional switch in the panel. And in emergency engine power loss situations, the autopilot also supports the Smart Glide engine-out navigation capabilities offered by G3X Touch flight displays or any of the GTN Xi navigators. You may also find it interesting to read more about Garmin’s ESP-X flight envelope protection system, as I have only scratched the surface in its capability.
Fly safe, fly often, and learn what your aircraft equipment can do before flying in IMC.
EDITOR’S NOTE: Michael J. “Mick” Kaufman is a Certified IInstrument Flight Instructor (CFII) and the program manager of flight operations with the “Bonanza/Baron Pilot Training” organization. He conducts pilot clinics and specialized instruction throughout the U.S. in many makes and models of aircraft, which are equipped with a variety of avionics. Mick is based in Richland Center (93C) and Eagle River, Wisconsin (KEGV). He was named “FAA’s Safety Team Representative of the Year” for Wisconsin in 2008. Readers are encouraged to email questions to captmick@me.com, or call 817-988-0174.
DISCLAIMER: The information contained in this column is the expressed opinion of the author only, and readers are advised to seek the advice of their personal flight instructor and others, and refer to the Federal Aviation Regulations, FAA Aeronautical Information Manual, and instructional materials before attempting any procedures discussed herein.