Trio Avionics EZ Altitude Control - Manual (Page 23)

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PCS
SELECT
VS
PCS
SELECT
AS
the encoder to enter a 500 fpm climb and press the LCD switch to engage the servo.
Once the aircraft is established in the climb, slowly retard the throttle until the airspeed
decays to the minimum airspeed that you have previously set. The LCD display should
flash red and indicate “MIN AS LIMIT”. Check to be sure that the system lowers the nose
of the aircraft so that the airspeed settles out at the minimum airspeed that you have set.
The display will flash green and display “MIN AS CAPT” as the autopilot continually
adjusts the elevator control to keep the speed at this limit.
The pilot should then check the maximum airspeed alarm limit by pressing the LCD to
return to the READY mode, then re-entering the VS mode by pressing the ENCODER
switch. Once the VS MODE message is displayed the pilot should dial in an appropriate
descent rate and then activate the command by pressing the LCD switch. When the
maximum airspeed limit is achieved the red LCD display should read MAX AS LIMIT and
the system should raise the nose of the aircraft to slow it to the prescribed limit. Here
again, as the speed slows, the display will flash a green MAX AS CAPT message after
the speed has decreased to the maximum airspeed setting. The autopilot will then adjust
the elevator to maintain a speed at the set limit.
8.1.4 Vertical Rate and Airspeed Track Pilot Command Steering (PCS)
The vertical rate and airspeed track PCS modes require that a remote servo disconnect
button be installed on the control stick or other location. If the aircraft is equipped with an
EZ Pilot autopilot, it is recommended that the same disconnect switch be used for the EZ-
2 (so that the common switch will disconnect both servos in the event of an emergency).
PCS operation is essentially the same as described in the EZ-1 section of this manual.
Pressing the remote disconnect switch disengages the servo. However, if the switch is
held down for 3 seconds it will “arm” the servo so that it will reengage when the switch is
released. Once released the autopilot will enter either the PCS VS mode (hold a vertical
rate) or the PCS AIRSPEED mode (hold the airspeed when released)
If the VS option (vertical speed) is selected in the SETUP menu, the
EZ-2 and EZ-3 allows the pilot to use the PCS function for vertical
speed (rate) climbs and descents. A typical scenario on using the
EZ-2 and EZ-3 for this function follows:
Assume that the VS option is selected; the system is in the ALT
HOLD mode and is maintaining a level altitude of 5,500 feet. If it is
necessary to climb to 7,500 feet the pilot may press and hold the
remote disconnect switch then manually fly the airplane at the desired climb rate. Once
the vertical speed is established and stabilized (and the system is armed), releasing the
switch will cause the system to engage the servo and continue the climb at that rate.
When the aircraft reaches 7,500 feet, pressing the LCD switch will put the system back
into the ALT HOLD mode.
PCS Airspeed Operation . If it is preferred, the pilot may use the PCS mode to
conduct a change in altitude based on airspeed rather than vertical speed.
The pilot must use the SETUP menu to configure the EZ-2 or EZ-3 PCS mode to use
airspeed instead of vertical speed. This is done by pressing and
holding the encoder knob until the system enters the SETUP
mode. Once in the SETUP mode, repeatedly press the encoder
until you arrive at a display that reads PCS SELECT VS.
Rotating the encoder knob will change the display to read “PCS
SELECT AS”. Once this display has been selected, exiting the
SETUP mode (by pressing and holding the ENCODER switch or