AUTOPILOT AWRY

jmk wrote:
Are you saying it doesn't work in ROLL mode, but does work in HDG mode?
Unusual, but if so then it's a pretty simple fix. The HDG switch
essentially disables the ROLL pot, so if it works okay in HDG but not
in ROLL, then either the switch is bad, or the POT is bad, not much
else involved.

Sorry, I should have clarified. Heading mode works, roll works (sort
of, I'll explain in a sec.). It is the other modes (NAV, OMNI, LOC, LOC
back course) that don't work.

For roll mode, if I turn the round roll knob slightly one direction, the
ailerons keep moving to the stops. If the knob is centered though, the
ailerons stay centered. I've only tried this on the ground. In the
air, heading mode works fine but none of the other modes mentioned above.


--
Jack Allison
PP-ASEL-IA Student
Arrow N2104T

"When once you have tasted flight, you will forever walk the Earth
with your eyes turned skyward, for there you have been, and there
you will always long to return"
- Leonardo Da Vinci

(Remove the obvious from address to reply via e-mail)

I thought that is the way it is supposed to work on the ground. I thought,
and I might be wrong on this, that the roll pot set a desired angle of bank,
not a desired aileron position. Next time I have some time, I will check
this out.

Just another data point for consideration: My auto pilot was not working
right on my arrow when I bought it ( or should I say it always worked
"right"). It would turn to the right in VOR/LOC modes. I had the shop look
at it along with other items on my squawk list. They fixed it with no parts
and about an hour of labor. I don't know what the problem was. Just goes to
show you that autopilots are not always expensive to get fixed. It is
definitely worth having someone look at it.

"Jack Allison" wrote in message
...
jmk wrote:
Are you saying it doesn't work in ROLL mode, but does work in HDG mode?
Unusual, but if so then it's a pretty simple fix. The HDG switch
essentially disables the ROLL pot, so if it works okay in HDG but not
in ROLL, then either the switch is bad, or the POT is bad, not much
else involved.

Sorry, I should have clarified. Heading mode works, roll works (sort of,
I'll explain in a sec.). It is the other modes (NAV, OMNI, LOC, LOC back
course) that don't work.

For roll mode, if I turn the round roll knob slightly one direction, the
ailerons keep moving to the stops. If the knob is centered though, the
ailerons stay centered. I've only tried this on the ground. In the air,
heading mode works fine but none of the other modes mentioned above.


--
Jack Allison
PP-ASEL-IA Student
Arrow N2104T

"When once you have tasted flight, you will forever walk the Earth
with your eyes turned skyward, for there you have been, and there
you will always long to return"
- Leonardo Da Vinci

(Remove the obvious from address to reply via e-mail)

Jack Allison wrote:
jmk wrote:

Are you saying it doesn't work in ROLL mode, but does work in HDG mode?
Unusual, but if so then it's a pretty simple fix. The HDG switch
essentially disables the ROLL pot, so if it works okay in HDG but not
in ROLL, then either the switch is bad, or the POT is bad, not much
else involved.

Sorry, I should have clarified. Heading mode works, roll works (sort
of, I'll explain in a sec.). It is the other modes (NAV, OMNI, LOC, LOC
back course) that don't work.

For roll mode, if I turn the round roll knob slightly one direction, the
ailerons keep moving to the stops. If the knob is centered though, the
ailerons stay centered. I've only tried this on the ground. In the
air, heading mode works fine but none of the other modes mentioned above.

That's OK - the autopilot rolls till the roll feedback
from the horizon gyro matches the request from the pot.

You're ordering a certain amount of roll. If the horizon
does not follow, turn more on the ailerons till the order
is fulfilled.

--

Tauno Voipio (CPL(A) - avionics engineer)
tauno voipio (at) iki fi