Monday, March 22, 2021

HAL Is My Copilot

Statute of Limitations

It is a little recognized fact that application of nicknames is subject to a statute of limitations. Nicknames must be bestowed when a relationship is relatively new or else they never stick. Case in point: I failed to name Warrior 481 when I acquired her 17 years ago. Any nickname that I give her now will feel forced after a long relationship without one. Imagine not naming a child for 17 years. Awkward.

However, it is a different story for newly installed equipment. "I named the autopilot HAL because it tried to kill us a couple of times," I explained to Ray while describing the first test flight with the new Garmin autopilot.

"I hate test flying autopilots," the mechanic declared with a passion forged by many years of experience.
Final Exam

I have a hard time learning anything deeply by reading the manual alone. I read initially to get the basics, go off and experiment with the actual thing, then read more to pick up the nuances I was unprepared to absorb on the previous round. It’s a cycle I repeat until it all clicks. Sometimes YouTube provides some useful intellectual spackle to fill in the gaps.

If only her designers from the mid-1970s could see her now...

Learning to use the Warrior's autopilot (HAL) proceeded exactly this way. A week after receiving my airplane back from maintenance, I decided that I was ready to put my understanding of the system to the test. While the autopilot's basic modes are not difficult to understand, some strategic thinking is required in transitioning between modes and navigational data sources. Basic cruise flight does not present much opportunity to really test this, but flying instrument approaches seems like an ideal stress test for "navigating" (pun intended) HAL's various capabilities. 
Back To Basics, the VOR-A
Date Aircraft Route of Flight Time (hrs) Total (hrs)
22 Mar 2021 N21481 SDC (Sodus, NY) - 5G0 (Le Roy, NY) - ROC (Rochester, NY) - SDC 1.7 2223.1

Before launching from runway 28 at the Williamson Sodus Airport, I pressed the TOGA (takeoff / go around) button. This brought the magenta chevron of the flight director's command bars to life on the G5 primary flight display (PFD), appearing at a typical takeoff attitude of 8° above the artificial horizon. The command bars were "hollow" to indicate that HAL was still sleeping.

I taxied onto the runway, slowly applying full power as I lined up on center line. At 55 knots, I pitched the nose to a takeoff attitude and, moments later, left the Earth to rise above the treetops. I activated HAL about 800 feet above the ground and removed my hands from the yoke. I would not touch it again until over an hour later while on a short final approach for home.

In takeoff mode, the airplane simply climbs straight ahead with wings level. I programmed the Le Roy Airport as my destination in the GPS, then loaded and activated the VOR-A instrument approach starting at the initial approach fix of the Geneseo VOR. I activated HAL's NAV mode to follow the magenta line of the GPS to Geneseo and programmed an indicated airspeed (IAS) climb to 4,000 feet at 90 knots. HAL responded by smoothly banking Warrior 481 to the southwest on a direct heading to Geneseo while pitching to 90 knots in the climb. [Note: I later realized that altitude pre-select works with TOGA mode.]

While HAL flew the airplane, I contacted Rochester approach to request flight following. Along the way, Warrior 481 reached 4,000 feet and leveled herself off. HAL transitioned from an indicated airspeed climb (IAS mode) to an altitude hold (ALT mode) and I verified the correct annunciations on the PFD.  I made some corresponding trim and power adjustments to set the airplane up for cruise.

ForeFlight ground track of HILPT and VOR-A approach to Le Roy

At the Geneseo VOR, HAL flew a textbook hold-in-lieu-of-procedure-turn (HILPT) maneuver using a parallel holding pattern entry. For VOR approaches, GPS guidance may be used up to the final approach fix (FAF), but the last five miles to the destination airport must be flown following the VHF radio beam emanating from the VOR. Outbound from Geneseo, I throttled back and instructed HAL to descend to 2600 feet (the FAF crossing altitude) with a -800 foot per minute descent.

One of HAL's quirks is that changing the navigation source (i.e., from GPS to VOR or vice versa) disengages NAV mode. I made the switch from satellite to terrestrial navigation, transforming the course deviation needle on the G5 flight display from magenta (GPS) to green (VOR/localizer) and re-engaged NAV mode. HAL continued to track toward the airport, now riding the radio beam from Geneseo.

HAL flew a perfect VOR approach to Le Roy, minus a few wiggles that I believe have more to do with the fidelity of the VOR signal itself than anything on board my ship. Not to be outdone by the fancy new box in my panel, I even remembered to start the timer from the FAF inbound! This made me feel useful while HAL did all the work. Humanity for the win! Once reaching the airport, I pressed the TOGA button and pushed the throttle all the way forward to climb away from my former home base.

Success! One down.

Once More, With Precision!

Being vectored for the ILS-22 at Rochester on a 030° heading

Back in two-way communication with the friendly neighborhood approach controller, I requested a practice ILS-22 instrument approach to Frederick Douglass-Greater Rochester International. I was assigned a heading of 030°, a course that took me west of Rochester on a slightly divergent line from the target runway. HAL handled this in HDG mode while I set up the rest of the approach and verified the Morse code identifier for the localizer. This was all much easier to do with “someone else” flying the airplane.

Heading 130° while being vectored for the ILS approach

I followed my usual workflow of activating the full approach in the Garmin 430W GPS and eventually activated the leg to the FAF once it was clear that Rochester was going to vector me to final. Overall, I found that HAL fit right into my usual procedural flow. Rochester then instructed a right turn to heading 130, roughly perpendicular to the final approach course. With the turn of a knob, I set the new heading and HAL smoothly banked Warrior 481 to follow. 

"This is just way too easy!" I exclaimed to no one, laughing. I reflected back on my days of instrument training and being task saturated while hand flying my first few approaches. Instead, I was doing the job of system manager while HAL flew the plane and I had lots of time to gawk at the world passing beyond the windows. The paradigm shift that came with this level of automation was jarring.

Established on the final approach course with HAL tracking localizer and glideslope

Then the magic words came, "Cherokee Four Eight One, three miles from MAPES, turn right heading two zero zero, cleared ILS 22 approach, maintain VFR."

After more twisting of the heading bug knob, HAL swung Warrior 481 onto an intercept course for the approach. I pressed the APR button to arm HAL's approach mode that would capture and track both the lateral guidance of the airport’s localizer array and the vertical glide slope. Approach mode would activate once interception of the final approach course was imminent.

Near the final approach course, approach mode automatically activated (with a LOC annunciation) and Warrior 481 turned an additional 24° to intercept the localizer. A few moments later, I reached the FAF at MAPES to the sound of the outer marker pulsing in my ears. Altitude hold automatically disengaged and HAL pitched the nose down to follow the glideslope to the runway (with a GS annunciation). I started the timer (photo above for proof!), eased the power back to the 1700 RPM necessary for a 90 knot, -500 foot per minute descent, and added a notch of flaps.

On the ILS for runway 22 at Frederick Douglass - Greater Rochester International

Under HAL's control, Warrior 481 flew that ILS like she was riding on a rail. It was nothing short of amazing. Usually I am under the hood while practicing approaches, so watching the big runway grow in my windscreen as I sat in my airplane with my hands on my knees was a very novel experience.

Two hundred feet above the runway, I pushed the TOGA button, added full power, and eased the flaps out. As HAL put the Warrior into a climb, I was switched to Rochester Departure.

Meet Up

"Cherokee Four Eight One, Rochester Departure, fly heading zero seven zero, vectors to Sodus." Back in HDG mode, I set the new course while HAL obligingly turned my ship toward home. I had just popped the side window open to capture a photo of the Rochester skyline when Departure called again.

"Cherokee Four Eight One... Chris, is that you?"

Why is it that these kinds of calls immediately make me think that I've just done something wrong?

Tentatively: "Affirm, Cherokee Four Eight One."

"Hey, it's Erik!" A couple of years ago, I organized a tour of Rochester's Air Traffic Control facility for the Williamson Flying Club. Erik was my primary contact and, in 2020, I vouched for Erik to join the Club. 

"Thanks for helping me test my new autopilot," I responded.

"How's it working?"

"Awesome," I said. Nonstandard radio phraseology, perhaps, but it made the point.

Irondequoit Bay

Recovering the Satellites

Passing the Williamson Sodus Airport. I can see my car! I wish I saw more green.

Once back in the vicinity of Sodus, I set up to fly the RNAV (GPS) 28 approach to wrap up the day and test approach mode using a GPS-generated glide path. Once again, HAL flew the approach procedure with aplomb.

A few hundred feet above the ground while on the approach, I hit the "nope" button to disengage HAL and hand flew my airplane to a passable landing at the Williamson Sodus Airport. It was my first time back on the controls since departure and I actually felt a little guilty logging the entire time aloft as piloting time. After all, there is no category for "systems management" time in the logbook.


As shown by ground track data from ForeFlight, HAL flies more precisely than I do. Kristy says that she can see the difference in FlightAware. In my time aloft, I tested HAL's takeoff and go around mode, performed indicated airspeed climbs and vertical speed descents to preselected altitudes, flew a procedure turn (HILPT), and executed three approaches using different navigation sources (VOR, localizer / glideslope, and GPS). The ILS and GPS approach procedures were an excellent opportunity to test HAL's approach mode that simultaneously tracks lateral and vertical guidance. It all worked perfectly.

While I expect that I will continue to learn nuances of the system, it is so intuitive that my comfort level with it is already very high. This is impressive considering that I had never touched an autopilot before HAL was installed.

Spa Day

Still grinning ear to ear from the success of my test flight, I reheated some leftover chicken with garlic sauce in the airport microwave and ate while lounging in the warm sun irradiating my south-facing hangar door. I realized that it was my first time using chopsticks at the airport. So many firsts that day.

I pampered my airplane with a well-deserved bath. I had moved her annual inspection with Ray back to February and she went directly from that to the avionics installation with Jake in Batavia. As a result, there were lots of greasy handprints on the airframe from the two shops. On top of that, the first good bath after a long winter is always truly satisfying.

For amusement and situational awareness, I tuned my handheld radio to listen on the Unicom frequency as I cleaned. Entertainment came courtesy of an apparently non-local aviator who entered the traffic pattern at nearby Canandaigua while repeatedly broadcasting his intentions to "Canon-dee-dee-wah". I stopped my scrubbing to giggle each time he said it. For the record, Canandaigua is pronounced exactly the way it's spelled despite a spectacular concatenation of vowels; it is certainly no Skaneateles ("skinny atlas").

"PhDs aren't supposed to do that," a quiet voice from an unseen speaker teased. I was on a creeper scrubbing oil and exhaust stains off the Warrior's belly and had not heard Denny approach. I turned to find him grinning at me kindly from his bicycle. "You're supposed to hire someone to do that."

I shrugged. "It's therapeutic." I had a nice catch up chat with Denny and earned a big smile from him when I restored his range rings display in ForeFlight. Sometimes, it's the little things.


Date Aircraft Route of Flight Time (hrs) Total (hrs)
22 Mar 2021 N21481 SDC (Sodus, NY) - ART (Watertown, NY) - SDC 1.6 2224.7

With the airplane thoroughly cleaned, I decided to reward us both with a little excursion to the northeast along the Lake Ontario shoreline. HAL remained dormant for this flight and the resulting ground tracks proved Kristy right. Though I fly reasonably precisely, the difference between my flying and HAL’s is definitely apparent in FlightAware.

There was still ice covering part of Henderson Bay

When the flying was done, I closed the hangar door on my clean, capable aircraft and departed the airport after one of my most satisfying vacation days in a long time. It is hard to believe that a year ago, the Warrior was stricken in Dansville and the path back home was unclear. The intervening year has been quite a journey.


  1. Excellent PIREP on Hal's operation. It's amazing just sitting there watching or managing systems, providing even more time to stay ahead of the plane. Briefing an approach plate will never be the same, read a complete section check system and traffic, proceed to the next section, completely review and then back to the systems.
    I really like the altitude pre-select, the one thing my Stec 60-2 is missing. The LVL button is a great safety feature too, overall an excellent unit.

    1. I’m still kind of dazzled by it, Gary. And the bang for the buck compared to the older autopilots is nothing short of amazing!

  2. my friend have missed your calling in creating stories for all of us to read. As always a very detailed should I say anal? - account of your endeavors. I wish I was in the Roc to chat w you. I seriously need to get off my butt and finish my journey to ascertain my license......the amount of days for flying down here would leave you broke for avgas!!!! Thanks yet again for a very informative review of your worthy endeavors!!!!

    1. Thanks, man! I remember that you soloed, but was wondering if you ever finished. Do it! There’s no time like the present!

  3. Well now I really want to get the Garmin AP! Love the G5s in the 182 but man would that level of integration be great.

    Likely an early to-do should we end up jumping onto the true ownership bandwagon here in the next couple years.

    1. It’s like having a completely different airplane.