Hi everyone,
I thought I'd share my experience in upgrading my airplane with a GFC-500 autopilot system, a second G5, and removal of the vacuum system.
After hand flying for 2200+ hours in VMC and IMC, I decided to invest in an autopilot as safety measure. My panel already had a G5 configured as an attitude indicator, an upgrade that I made after a mechanical gyro failure in IMC in 2017 while flying over Hamilton, ON between Detroit and my home in Rochester, NY. Ever since, I've been completely enamored with the idea of adding a second G5 for redundancy and to eliminate the vacuum system because I never really trusted those balky pumps.
I configured the autopilot as a two-axis system (no trim servo and, probably not surprisingly, no yaw dampener). My shop took about three weeks to do the work, including a delay caused by them ordering the wrong mounting bracket for the pitch servo. There's one for mounting under the backseat and a different one for mounting in the tail next to the ELT -- my battery is under the back seat, which precluded mounting the pitch servo there.
Test Flight #1: I did the test flight with another pilot experienced in GFC-500 operation. Asking the AP for a gentle climb or descent resulted in a aggressive pitch in the opposite direction. When we tested the "LVL" button, the airplane promptly dove for the Earth. Fortunately, the AP disconnect button worked every time (I now call it the "nope" button). It was not a great start. Long story short, the shop programmed the system incorrectly. The problem was rectified within a few minutes of the technician making changes in the configuration menu on the G5. I've named the autopilot "HAL" on account of it trying to kill us a few times due to a programming error. Seemed appropriate.
Test Flight #2: Though I had been studying the manuals and had watched Garmin's training videos, I was still an autopilot newbie that had never actually used one before. I mention this only to emphasize how intuitive the system was to use. On that second test flight, I used several of the basic functions and had the autopilot fly a procedure turn and a portion of an instrument approach. The autopilot response was very smooth. After a sketchy first test flight, the system has worked flawlessly ever since.
Within a week of picking up the airplane, I took off from my home airport, activated the AP 800 feet off the ground, and flew a VOR, an ILS, and an RNAV w/ LPV approach without touching the yoke again (except to key the mic) until on short final for my home airport about 1.5 hours after launch. This included using heading mode, approach mode (for lateral and vertical guidance on the ILS and the RNAV), indicated airspeed climbs and vertical speed descents to preselected altitudes, using the go-around button at the DA/MDA of each approach, holds, and procedure turns. Ground tracks are extraordinarily crisp, though there was some wiggle when I used the VOR as guidance that was probably more about the fidelity of the VOR signal in that location than anything with my onboard equipment. Interceptions were very crisp and it flew the ILS and RNAV approaches like we were on a rail. No oscillations around the localizer. I did a -800 foot/min descent to a preselected altitude and the autopilot captured the target altitude very crisply and smoothly. All I had to do was manage trim and power.
I thought I'd share because it was a massive step up in terms of capability for me and the system performance truly exceeded my expectations.
Above: Work in progress
Above: All finished. Yes, I still have a 47 year old radio in my panel. I've been waiting years for it to die and it simply won't. The shop took it on themselves to repaint it and replace the ancient coax to the antenna. The KX-170B hasn't looked or sounded this good in years.
Above: Being vectored for the ILS-22 at KROC. I received one more vector and was cleared for the approach after this photo was taken, at which time I armed approach mode. Within a dot of the localizer, approach mode went active and the airplane intercepted the localizer. When we intercepted the glideslope at the FAF, altitude hold mode automatically cancelled and the AP annunciated "GS" to indicate that it was now following the glide slope. The unit intelligently sequences from mode to mode as needed.
I thought I'd share my experience in upgrading my airplane with a GFC-500 autopilot system, a second G5, and removal of the vacuum system.
After hand flying for 2200+ hours in VMC and IMC, I decided to invest in an autopilot as safety measure. My panel already had a G5 configured as an attitude indicator, an upgrade that I made after a mechanical gyro failure in IMC in 2017 while flying over Hamilton, ON between Detroit and my home in Rochester, NY. Ever since, I've been completely enamored with the idea of adding a second G5 for redundancy and to eliminate the vacuum system because I never really trusted those balky pumps.
I configured the autopilot as a two-axis system (no trim servo and, probably not surprisingly, no yaw dampener). My shop took about three weeks to do the work, including a delay caused by them ordering the wrong mounting bracket for the pitch servo. There's one for mounting under the backseat and a different one for mounting in the tail next to the ELT -- my battery is under the back seat, which precluded mounting the pitch servo there.
Test Flight #1: I did the test flight with another pilot experienced in GFC-500 operation. Asking the AP for a gentle climb or descent resulted in a aggressive pitch in the opposite direction. When we tested the "LVL" button, the airplane promptly dove for the Earth. Fortunately, the AP disconnect button worked every time (I now call it the "nope" button). It was not a great start. Long story short, the shop programmed the system incorrectly. The problem was rectified within a few minutes of the technician making changes in the configuration menu on the G5. I've named the autopilot "HAL" on account of it trying to kill us a few times due to a programming error. Seemed appropriate.
Test Flight #2: Though I had been studying the manuals and had watched Garmin's training videos, I was still an autopilot newbie that had never actually used one before. I mention this only to emphasize how intuitive the system was to use. On that second test flight, I used several of the basic functions and had the autopilot fly a procedure turn and a portion of an instrument approach. The autopilot response was very smooth. After a sketchy first test flight, the system has worked flawlessly ever since.
Within a week of picking up the airplane, I took off from my home airport, activated the AP 800 feet off the ground, and flew a VOR, an ILS, and an RNAV w/ LPV approach without touching the yoke again (except to key the mic) until on short final for my home airport about 1.5 hours after launch. This included using heading mode, approach mode (for lateral and vertical guidance on the ILS and the RNAV), indicated airspeed climbs and vertical speed descents to preselected altitudes, using the go-around button at the DA/MDA of each approach, holds, and procedure turns. Ground tracks are extraordinarily crisp, though there was some wiggle when I used the VOR as guidance that was probably more about the fidelity of the VOR signal in that location than anything with my onboard equipment. Interceptions were very crisp and it flew the ILS and RNAV approaches like we were on a rail. No oscillations around the localizer. I did a -800 foot/min descent to a preselected altitude and the autopilot captured the target altitude very crisply and smoothly. All I had to do was manage trim and power.
I thought I'd share because it was a massive step up in terms of capability for me and the system performance truly exceeded my expectations.
Above: Work in progress
Above: All finished. Yes, I still have a 47 year old radio in my panel. I've been waiting years for it to die and it simply won't. The shop took it on themselves to repaint it and replace the ancient coax to the antenna. The KX-170B hasn't looked or sounded this good in years.
Above: Being vectored for the ILS-22 at KROC. I received one more vector and was cleared for the approach after this photo was taken, at which time I armed approach mode. Within a dot of the localizer, approach mode went active and the airplane intercepted the localizer. When we intercepted the glideslope at the FAF, altitude hold mode automatically cancelled and the AP annunciated "GS" to indicate that it was now following the glide slope. The unit intelligently sequences from mode to mode as needed.
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