Trio Avionics EZ Altitude Control - Manual (Page 22)

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Note: Because of the inertia of the airframe in any flight mode, the
system cannot correct instantaneously. It is therefore very important
that the Minimum and Maximum limits be set with a significant margin
to allow for some overshoot of the limit airspeeds.
MAX
AS
LIMIT
MAX
AS
SET
MAX
AS
CAPT
MIN
AS
SET
MIN
AS
CAPT
MAX
AS
LIMIT
MIN
AS
LIMIT
the aircraft will begin to climb. The pilot will likely advance the engine power to keep the
speed up during the climb. Now let’s assume that the pilot rotates the encoder to
command a 2,000 fpm climb. Most aircraft will not be able to achieve such a vertical rate
and the aircraft will approach a stall. As the airspeed falls to the Minimum Airspeed Limit,
the LCD display will flash red and display “MIN AS LIMIT” and the system will issue a
pitch down command to the servo to prevent a stall. Once the airspeed increases back
above the minimum alarm airspeed, the LCD will display a flashing green MIN AS CAPT
message and then track that minimum airspeed instead of the commanded vertical rate.
The aircraft will continue to climb, but will be adhering to the airspeed limit instead of the
commanded vertical rate.
Similarly, if a steep descent is commanded and the airspeed
reaches the Maximum Airspeed limit, the LCD display will flash
red and display MAX AS LIMIT and the system will reduce the
descent rate to keep the aircraft from exceeding the limit speed.
Once below the maximum alarm the LCD will display a flashing
green MAX AS CAPT message and then track that maximum
airspeed. In the ALT HOLD mode only the minimum airspeed
limit will be sensed. This allows the pilot to fly straight and level at airspeeds above the
maximum airspeed limit.
8.1.3 Setting Minimum & Maximum Airspeed
The MIN and MAX airspeed limits are set in flight by flying the aircraft manually to the
airspeed desired and then entering that pitot pressure value into the system. This is
done automatically by simply pressing the LCD switch as follows:
With the EZ-2 or EZ-3 in the “READY”
mode, press and hold the encoder
button until the system is in the SETUP
menu. Then momentarily press the
encoder button repeatedly until the
amber display reads “MIN AS SET”.
Slow the aircraft to the desired minimum
airspeed (giving plenty of margin before
a stall) and press the LCD switch. The
display will be green and read “MIN AS
CAPT” as the airspeed is captured in
nonvolatile memory.
Momentarily press the encoder button
again and the amber display will read
“MAX AS SET”. Now fly the aircraft to
the maximum desired speed and once
again press the LCD switch. The display
will read “MAX AS CAPT”.
Press and hold the encoder button to exit
the SETUP mode. Once the system is in
the READY mode, press the encoder
button to enter the VS MODE. Rotate