• Skip to primary navigation
  • Skip to main content
General Aviation News

General Aviation News

Because flying is cool

  • Pictures of the Day
    • Submit Picture of the Day
  • Stories
    • News
    • Features
    • Opinion
    • Products
    • NTSB Accidents
    • ASRS Reports
  • Comments
  • Classifieds
    • Place Classified Ad
  • Events
  • Digital Archives
  • Subscribe
  • Show Search
Hide Search

Bonanza pilot surprised by autopilot

By NASA · July 6, 2022 ·

This is an excerpt from a report made to the Aviation Safety Reporting System. The narrative is written by the pilot, rather than FAA or NTSB officials. To maintain anonymity, many details, such as aircraft model or airport, are often scrubbed from the reports.

On short final to a visual landing, the autopilot (which was turned off) pushed the nose towards the ground. I was surprised. I pushed and held the autopilot disconnect, recovered, and landed.

I was familiar with the ESP (Electronic Stability & Protection) feature on my recently installed Garmin GFC 500 autopilot in theory, but seeing it in practice was scary.

Landing speeds for my Bonanza 33 are 64 to 70 knots depending on weight per the POH. I was light, winds were light, and I intended on landing at 68 knots. The GFC 500 ESP pushes the nose down below 70 knots.

Note that a V Tail bonanza with the exact same flight characteristics has a GFC 500 ESP speed of 65 knots, which is better.

This is a hazard that needs a software modification to correct.

Primary Problem: Aircraft

ACN: 1873529

About NASA

NASA's Aviation Safety Reporting System (ASRS) captures confidential reports, analyzes the resulting aviation safety data, and disseminates vital information to the aviation community.

Reader Interactions

Share this story

  • Share on Twitter Share on Twitter
  • Share on Facebook Share on Facebook
  • Share on LinkedIn Share on LinkedIn
  • Share on Reddit Share on Reddit
  • Share via Email Share via Email

Become better informed pilot.

Join 110,000 readers each month and get the latest news and entertainment from the world of general aviation direct to your inbox, daily.

This field is for validation purposes and should be left unchanged.

Curious to know what fellow pilots think on random stories on the General Aviation News website? Click on our Recent Comments page to find out. Read our Comment Policy here.

Comments

  1. Adam says

    August 6, 2022 at 2:13 pm

    I have now had this happen twice to my Vans RV 12 with Dual Garmin g3x.

  2. Tim says

    July 9, 2022 at 9:11 am

    I had a very similar experience, also in a Bonanza with a GFC500. The avionics had been recently installed, and I had only a few hours flying it. I had read the book, and knew about ESP and the fact that it’s always lurking, even with the autopilot disengaged. That level of knowledge didn’t help at all during the event. ESP aggressively pushed the nose down on final approach although the speed was entirely safe for the aircraft weight and configuration, and it was surprising how much force was required to overcome it. I didn’t think about disconnecting the autopilot, because it already was… It’s the only time my wife has ever been scared in an airplane. I’ll note that with my system, which has a G3X, the ESP engagement parameters can be changed in the G3X setup mode.

  3. Craig Sooter says

    July 8, 2022 at 2:16 am

    Folks… when you install new technology in an old bird ya better Fully understand the systems. Too many jump on the bandwagon of being ignorant and blaming the system design. The ESP is a good design and one must fully understand it if installed.

  4. Bob says

    July 7, 2022 at 1:00 pm

    Wow, sounds like the 737 TCAS issue. That would be scary, you think when something is turned off, it is disabled.

    • Wylbur Wrong says

      July 7, 2022 at 5:09 pm

      Exactly what I thought when I first read this. I just didn’t want to be the first to say it.

    • Robert Hartmaier says

      July 9, 2022 at 5:08 am

      I have never heard that the 737 had any issues with the “TCAS” system, which is for traffic avoidance.

      • Wylbur Wrong says

        July 9, 2022 at 7:54 am

        Too many TLAs in this industry.

      • Bob says

        July 9, 2022 at 8:24 am

        Sorry, meant MCAS.

  5. Jimmy says

    July 7, 2022 at 5:03 am

    I have a plastic zip tie around the circuit breaker for my autopilot in order to make it very easy to identify the autopilot circuit breaker: for positive disabling if there is interference in flight controls. No trouble shooting needed.

    Autopilot has both electric and auto-trim plus Yaw damper.

© 2025 Flyer Media, Inc. All rights reserved. Privacy Policy.

  • About
  • Advertise
  • Comment Policy
  • Contact Us
  • Privacy Policy
  • Writer’s Guidelines
  • Photographer’s Guidelines