FMA Direct
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Co-Pilot II reference manual
Operating details
About flight stabilization
Co-Pilot™ II “looks” at the horizon with infrared heat sensors
(this same technology is used in thermal imaging cameras). The
Earth is warm (even when covered with snow) below the hori
-
zon, while the sky is cold above the horizon. Co-Pilot II “sees”
this temperature difference. When Co-Pilot II senses changes in
aircraft attitude relative to the infrared horizon, it sends correc-
tive signals to the servos to keep the aircraft level.
Flying with Co-Pilot II is easy. When you center the control
sticks, Co-Pilot II automatically returns the aircraft to level flight.
Co-Pilot II works over a wide range of weather conditions. Con-
tinuous monitoring by the optional Vertical Sensor Module (or a
simple manual calibration) adjusts Co-Pilot II to the local envi
-
ronment.
Co-Pilot II is an excellent teaching aid because it maintains
stable flight while the student develops flying skills (the key is
to center the sticks to regain control). Advanced pilots find Co-
Pilot II is useful for flying—and landing—under windy condi
-
tions. Because it responds much faster than you can, Co-Pilot II
can help tame an unstable aircraft, and is ideal for maintaining
control during your first flights with a new model.
If your transmitter has an unused channel, you can control Co-
Pilot II from the ground. Turn it on when it’s needed, and turn it
off when it isn’t needed.
Co-Pilot II uses patented technology to sense the difference in
infrared temperature (heat) between the Earth and sky. The sky
is always at a relatively lower infrared temperature, while the
infrared signature of the Earth is always relatively warmer. The
Main Sensor Module (illustrated below) contains four infrared
sensors oriented at 90° intervals, with opposite sensors working
as a pair. When one pair of sensors sees a change in an aircraft’s
orientation relative to the earth’s infrared horizon, Co-Pilot II is-
sues signals to the control system to bring the aircraft back into
level flight.
2
3
4
1
main
sensor
120°
When the model is flying above the Earth (even a few feet), each
sensor surveys several square miles, all the way to the Earth’s in-
frared horizon. The infrared temperature seen for the Earth is an
average of infrared generated from all terrain features. Co-Pilot
II interprets input from the sensors and applies compensation to
the servos controlling roll and pitch.
Other optical flight stabilization systems work with visible light,
not infrared. Those systems are strongly affected by changes
in cloud cover and other weather conditions, and don’t operate
well at sunrise, dusk or in the dark. The heat (infrared) radiating
from the Earth measured by Co-Pilot II provides a more stable
and precise reference than light or other phenomena. This gives
Co-Pilot II much more precision than visible light stabilization
systems. For example, Co-Pilot II won’t cause the aircraft to
wander when a cloud comes into view.
Since the infrared environment is not affected by variations in
visible light levels, an airplane equipped with Co-Pilot II could
be flown at night (but we don’t recommend this!). Only sub
-
stantial changes in weather cause gradual variations in infrared
temperature throughout a day. Heavy fog, flying through clouds,
or snow on the ground cause the infrared signature to vary. Also,
as a model flies over the terrain, there is some variation in the
average infrared temperature. For this reason, Co-Pilot II’s Verti-
cal Sensor Module performs continuous calibration (not available
in other flight stabilizers) that fine-tunes performance for near-
perfect stabilization under all conditions.
Understanding infrared calibration
Co-Pilot II’s Main Sensor Module sees for many miles in all
directions when the model is airborne. Its field of view will
include grass, trees, buildings, pavement, people, cars, clouds,
water and many other objects with different infrared emissions.
The Main Sensor Module detects an average infrared temperature
sufficient for Co-Pilot II to carry out flight stabilization under
nearly all conditions.
If the optional Vertical Sensor Module is installed, Co-Pilot II
uses information from it to continuously monitor the temperature
difference between sky and ground.
If the Vertical Sensor Module is not installed, you must perform a
manual infrared calibration (the “DO FIELD CALIB.” option ap
-
pears in the IRNet Programmer’s Main Menu when the Vertical
Sensor Module is not detected). Manual calibration measures in
-
frared temperatures in the immediate vicinity of the model. This
means that you should calibrate over an area representative of the
general infrared environment—such as grass—the Sensor will
see when the model is airborne. Once calibrated, large variations
in terrain or weather can affect Co-Pilot II’s ability to stabilize
the aircraft. If these occur, you may need to perform another
manual calibration.
You should
not
manually calibrate, for example, over asphalt
(such as a taxiway, runway or parking lot). If you were to cali
-
brate over asphalt, the Sensor would detect the infrared generated
by the asphalt—not the average for the larger area in which the
model will be flying—resulting in a falsely high temperature dif
-
ference.
In its Preflight check, Co-Pilot II tells you about the infrared tem
-
perature difference it measures. In several years of testing flight
stabilization technology, we’ve made some important observa-
tions:
n
Co-Pilot II rarely measures a difference greater than 60°F
(33°C).
n
Co-Pilot II even more rarely measures a difference of less than
10°F (5.5°C).
