Navaid Devices AP-1, Руководство пользователя

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Obviously, putting in a fix at low speed can adversely affect high-speed response, and
vice versa. It may be necessary to accept a compromise.
CALIBRATING THE DISPLAY
For your information, the RIGHT and LEFT CAL trimpots affect nothing but the number
of bars lit for a given rate of turn. Also, the direction is opposite of what you probably
would expect: clockwise rotation of these two trimpots causes a decrease in the number
of bars lit for a given rate of turn.
Disengage the autopilot and make a 360 degree standard turn to the right. Keep six bars
lit out to the white triangle and time the turn. If it takes less than 2 minutes to complete
the turn, set the RIGHT CAL trimpot halfway between wherever it is and fully
clockwise; conversely, set it half way to fully counterclockwise if the timed turn takes
longer than 2 minutes.
Make another timed turn, and correct as before but with only half as much correction, i.e.,
about 30 degrees of trimpot rotation. If that is not close enough, repeat the process again
using half the previous correction. Three or four successive approximations for RIGHT
CAL ought to get the time fairly close to the desired 2 minutes for a right turn. Repeat the
procedure on standard left turns, this time adjusting the LEFT CAL trimpot.
The accuracy with which one can fly a timed turn is limited by the resolution of the
display, which in this case is plus or minus 1/4 degree per second, as well as pilot
technique and turbulence. The above procedure calibrates the readout so that a six bar
rum gives a turn rate fairly close to 3 degrees per second, and the pilot is a component in
the feedback loop, so this calibration method is probably as good as any.
MEASURING THE MAXIMUM TURN RATE
The maximum turn rate that can be commanded with the TURN CONTROL cannot be
adjusted, but it is repeatable and can easily be measured. The measured value ought to
turn out to be a little less than 3 degrees per second.
Measure the time required for a 360 degree autopilot turn with the TURN CONTROL
fully clockwise. Divide the time, in seconds, by 360. The answer is the measured turn
rate. You may want to placard the instrument panel with the required number of seconds
for a 180 degree turn each way.