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http://www.eagletreesystems.com
Safety Mode Menu
NOTE: carefully read the Safety Mode Overview section before changing these settings!
•Run Safety Mode Wizard: This invokes the safety mode configuration wizard, described below.
•Reset Cruise Sticks & Throtl: Recaptures the model’s aileron/rudder, elevator, and throttle settings for level flight. These settings are captured
during the Safety Mode wizard, but sometimes these need to be recaptured, if you have retrimmed your plane. NOTE: the throttle needs to be
set at “cruising speed” position when this option is selected!
•Select Desired Safety Mode: Selects one of the safety mode options. None: no safety mode enabled. Failsafe: selects the failsafe mode. Rtrn
Home: selects the Return to Home safety mode.
•Choose Model Control Type: Selects the type of control surfaces you use on your model. For “traditional” fixed wing models, which use
ailerons/rudder and elevator, choose “Standard.” For models that use elevon or vtail mixing, such as “flying wings” choose “Elevon.”
•Choose Receiver Type: Sets the type of Radio/Receiver you are using. There are two options. PPM/No FS: this option should be chosen if your
receiver stops controlling the servos if you turn off your radio (or the servos start moving randomly). PCM/FS: this option should be chosen if
your receiver holds the last servo position (or goes into a failsafe position) when the radio is turned off. Most, but not all, 2.4GHz radios (such as
Spektrum
TM
and Futaba
TM
2.4GHz radios) are PCM. If you are unsure of the mode, turn off your radio, and gently move one of the servo arms
while the receiver is still powered. If the servo moves without resistance and stays in the new position, or your servos start moving randomly, select
“PPM/No FS” receiver mode. Otherwise, choose the “PCM/FS” mode.
•Number Failsafe Chans on RX: If your radio does not have any failsafe channels programmed, set this to “No FS Chs.” If your receiver only
supports throttle failsafe, and you have programmed a throttle failsafe position with your radio, select “1 FS Chns.” If your radio supports failsafe
positions on your elevator, aileron/rudder, and throttle channels, and you have programmed failsafe positions on all of these, choose “3+ FS Chns.”
WARNING: if you are using a PCM radio, and choose “No FS Chs,” the selected safety mode will activate whenever the radio sticks are
not moved for a short period of time. Therefore, it is strongly recommended that you program failsafes into your receiver, and select either
1 or 3+ failsafe channels in this menu item.
•Cruise Speed: This parameter sets the desired (optimal) cruise speed of your model (or set “0” to disable this feature). Set this parameter to the
approximate speed at which your model maintains level flight (either MPH or K/H, depending on units). This should be the speed of the model for
it to maintain level flight. Note that when you run the Safety Mode Wizard, and are prompted to set throttle for Cruise Speed, you should adjust
your throttle stick position so that it sets a speed at which the model maintains level flight, assuming no turns are being made. So, your throttle
setting during the Safety Mode Wizard should result in the approximate speed that you enter here for Cruise Speed. IMPORTANT: The primary
feature of this setting is to attempt to avoid throttling up in a dive, since during a dive the model’s speed would presumably exceed the Cruise Speed
setting. If you set this to a non-zero value, RTH will not throttle up to your “Climb” throttle setting if the present speed of your model is greater
than the value you set here for Cruise Speed.
•Cruise Altitude (300/120): Set this parameter to the desired altitude which the Return to Home feature should attempt to maintain. If there are
obstacles between your model and home that have higher elevation than this setting, the model may crash into them, so consider this in your setting.
Of course, never set this value above the legal flying limit for your area. This setting is in Feet if you have configured your system for English units,
or in meters if you are configured for Metric units. The default values for (English, Metric) are show in the menu item in parentheses.
•Altitude Error(100/40): This setting has two purposes. First, this setting controls the tolerable window of altitude above and below the Cruise
Altitude setting, referred to as the “Cruise Altitude Window.” For example, if Cruise Altitude is set to 300, and Altitude Error was set to 100, the
Cruise Altitude Window would be between 200 and 400. Never set this value so that this value, when added to “Cruise Altitude” parameter above,
exceeds the legal flying limit for your area. Secondly, this setting is also used as the limit to the input of the pitch PID controller. See below.
The default values for (English, Metric) are show in the menu item in parentheses.
•Pitch Proportional Gain (50): This setting adjusts the proportional input to the elevator PID controller. The default value is shown in
parentheses. The elevator PID controller examines the difference between the present altitude, and the desired Cruise Altitude. If the difference is
greater than the Altitude Error setting above, the difference is limited to Altitude Error. Then, the elevator controller multiplies this difference by
the Pitch Proportional Gain value.
•Pitch Derivative Gain (50): This setting adjusts the derivative input to the elevator PID controller. Higher values of this setting damp (reduce)
the climbrate. The effect of this parameter is increased as the Cruise altitude is approached, which reduces overshoot. Increase this parameter if
the model “porpoises” between too high and too low, during testing. Decrease the value if the model stops climbing too soon or too abruptly.
•Turn Proportional Limit (20): this setting controls the maximum error that the heading controller will accept as an input. The heading
controller examines the present heading, and the heading for home. If the difference in these headings is greater than Turn Proportional Limit, the
Turn Proportional Limit value is used instead. The default value is shown in parentheses.
•Turn Proportional Gain (50): This setting amplifies the proportional input to heading controller. The default value is shown in parentheses.
The heading controller determines the present heading, and the desired heading for home. The difference in headings (limited by Turn
Proportional Limit as described above) is then multiplied by Turn Proportional Gain.
•Turn Derivative Gain (50): This setting adjusts the derivative input to the heading PID controller. Higher values of this setting damp (reduce)
the rate of turn. The effect of this parameter is increased as the correct home heading is approached, which reduces overshoot. Increase the value
of this parameter if the plane continues to turn after reaching the correct home heading. Decrease the value if the model stops turning too soon, or
stops turning too abruptly.
•Turn Integral Gain (50): This setting controls the integral input to the heading PID controller. The heading PID controller examines how long it
is taking to turn to the correct home heading. As time passes during the turn, the aileron/rudder is turned more and more, to increase the rate of turn
over time. Normally the impact of the integral gain should be small. But, if a strong wind or other factor is keeping the plane from reaching home
in a reasonable amount of time, integral gain will continue to increase the turn rate.
