I flew with a friend to the Bay Area in Foxtrot today. It was a beautiful day, and I took the time to experiment with the standard autopilot a bit – the original Century II single axis wing-leveler. After 18 years of flying Pipers and never really using the autopilot to satisfaction, I discovered a few things today that may be useful…
1. Rudder Trim – When course deviation is small, the bank angle the autopilot provides is very small, and at some point was not even enough to make the plane turn. I discovered the obvious: you need to adjust rudder trim in combination with the AP to actually level the wings and hold course. What I discovered by trial and error is actually described well in the manual here: Century IIB Operating Manual
2. It takes some practice to maintain altitude with the AP on. It is different feeling, and in the beginning, I had 150ft swings both ways, while trying to really maintain altitude precisely. Practice, as in many situations, does bring improvement – and indeed I was getting better after doing this for a little while. Who would have thought flying with the autopilot requires additional practice in basic flying.
3. Having the AP do turns does not work without very significant assistance in keeping pitch. A 60 degree turn will significantly drop the nose, so you have to use the yoke to hold up the nose manually. More practice.
After reading the manual (finally), I picked up a few more things.
4. What I did learn about the AP during primary training was that in preflight, you need to test the AP, as well as the effective disconnection of the AP when you pull the breaker. The manual, in contrast, states that you need to test that you can overpower the AP with about 15lbs of force. That’s good, because we don’t have a breaker you can pull for the AP.
5. There is a non-trivial procedure for tracking navaids. For one, you need to put the OBS and the heading bug at the same course for it to work. Now I know why I couldn’t get that to work. The 4 available settings, I believe I now understand, are different dampening settings – and NAV can be used for enroute, OMNI for VOR approaches, LOC NORM for ILS/Localizer approaches, and LOC REV for localizer backcourses. Something to play with during a later flight.
Based on this experience, I am getting a better appreciation for the value that even a simple wing leveler can bring to flight. I also now think that autopilot use requires a lot more attention in primary training, and especially again in instrument training. Proper AP use doesn’t just require knowledge of how to operate the technology, but also requires some flying skills, that require practice to master. With that, I think the ubiquitous century wing leveler can be a great help in both VFR and IFR environments.