Navaid Devices AP-1, Руководство пользователя

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If your GPS or LORAN allows you to program in a course offset, you can do the
signal test on the ground. Program in a course offset to the right, followed by an
offset to the left, and see if the ailerons move in the proper direction. You can
accomplish the same thing if you can program in a point of origin for a trip other than
your present (ground) position, i.e., plug in an origination point 5 miles away.
Also you can check out a VOR signal on the ground, assuming you can receive a
VOR signal. Just move the OBS to sweep the needle toward, say, the "FLY RIGHT"
side of the dial and watch for right roll direction of aileron deflection.
If there is no signal at the AP-1, check to see if the shield, which is grounded at the
AP-1, could be shorted to either conductor. You may not be able to see it if this is the
case, but an ohmmeter will read zero resistance between the shorted signal wire and
the shield. Then check continuity to the receiver on both wires.
C) Check for problems in the aileron control system.
LongEZ, Varieze, and Cozy airplanes give the most trouble as a result of friction.
They all have a good bit of play in the linkage, which is not so harmful if the
relatively high pressure air on the bottom surface of the ailerons is sufficient to blow
the ailerons up and thereby take the slack out of the system. If you are still building,
please take all possible precautions to insure a friction free system.
When the airplane is tracking a GPS or LORAN in the standard cruise (1 mile per
dot) mode, it has to move out about 0.35 miles from the track centerline to transit the
dead zone. At about a half mile from centerline an unloaded servo will move the
max. radius crank arm hole only about 0.01 inch, which means that this movement
will be lost if there is any slack in the system. A maximum track error signal
(150mV) at the AP-1 input probably moves the max. radius crank arm hole only
about 0.17 inch (varies-depends on adjustments).
The "feel" of the ailerons is largely determined by the designer, but some airplanes of
a given species have unusually "heavy" ailerons. One way this can happen (there may
be others—I am not competent in this area) is by the builder increasing the thickness
of the control surface trailing edge. He will end up with a stiffer system than was
intended.
The problem with stiff ailerons is that the servo must exert extra force to move the
ailerons. This means that the airplane has to drift further from the desired coarse to
pick up a larger error signal to make the servo work harder.