turbodakota
Well-Known Member
- Joined
- Jul 6, 2018
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Autopilot problems. 1979 Turbo Dakota has a Piper Autocontrol IIIB and a STEC 60 PSS for vertical. The STEC 60 PSS was put in in 2007. They have both worked well.
The IIIB started acting up in early December but started working fine again later in the month. Sometimes when activated it would rock side to side progressively in a steeper bank until turned off. The STEC worked fine and always engaged if the IIIB switch was on. The STEC is slaved to the IIIB. If you turn off the IIIB, the STEC disengages. Makes sense.
Two things have happened that could be contributing or a pure coincidence. My attitude indicator was overhauled. But after installation the IIIB worked fine for a month. The attitude indicator is connected to IIIB.
I just had a EDM 830 put in. A Garmin CDI/OBS connected to Nav2/430 was removed to make room.
Now when turning on the IIIB nothing happens. It should be in roll steering mode and when you move the roll steering knob I CAN hear the servo moving. But no aileron/control movement. Also and most interesting the STEC will no longer engage at all when the IIIB is on even though it passes all self tests with expected elevator movement. I also hear a squealing sound in my headset after turning ON the IIIB. It goes away after I turn it off.
Yeah. Weird. Any ideas before I take it to get looked at? [emoji857][emoji857][emoji857]
The IIIB started acting up in early December but started working fine again later in the month. Sometimes when activated it would rock side to side progressively in a steeper bank until turned off. The STEC worked fine and always engaged if the IIIB switch was on. The STEC is slaved to the IIIB. If you turn off the IIIB, the STEC disengages. Makes sense.
Two things have happened that could be contributing or a pure coincidence. My attitude indicator was overhauled. But after installation the IIIB worked fine for a month. The attitude indicator is connected to IIIB.
I just had a EDM 830 put in. A Garmin CDI/OBS connected to Nav2/430 was removed to make room.
Now when turning on the IIIB nothing happens. It should be in roll steering mode and when you move the roll steering knob I CAN hear the servo moving. But no aileron/control movement. Also and most interesting the STEC will no longer engage at all when the IIIB is on even though it passes all self tests with expected elevator movement. I also hear a squealing sound in my headset after turning ON the IIIB. It goes away after I turn it off.
Yeah. Weird. Any ideas before I take it to get looked at? [emoji857][emoji857][emoji857]
