The MAAA has listed a few issues lately with large models using powerboxes where it appears that failsafe did not work properly. Losing a large model is heartbreaking, but smaller models would benefit from using failsafe as well. So would your wallet.
Hearing talk in the pits, it was apparent that people would like to use failsafe, but were worried that it was complicated and beyond them. I had a look at my own models, and the internet and thought a starter article would be of use to members. As always, test and retest on the ground. Being cautious is a good trait. It is quite easy, and only takes a few moments.
Below are listed the means to program in failsafe in three of the most popular transmitters and systems in use.
You SHOULD DEFINITELY read the manual that came with your tranmsmitter to make sure that these apply to your model transmitter. The internet is very good at propagating mistruths. YOU are responsible for your models.
In all cases, you should enlist the help of another person to restrain the model, and test before launching your beast into the air whenever anything is changed. Testing on the ground is vital, as it is easy to overlook something like a reversed throttle position if you have not verified this.
In any case, you have to assume that if the FailSafe is activated, the model becomes a large free flight model. Idle throttle, neutral or slight up elevator, level ailerons and a small amount of rudder should see a circular glide to the ground in the event it is activated. Much better than a full throttle bore into the distance.!.
All this assumes your model flies straight and true with no control input. If you haven’t trimmed out your model properly, the result may be spectacular but brief.
Where possible, I have cut and pasted directly from the manufacturers manual, but you owe it to yourself to confirm with your own manual!
None of these operations take much time. Heck, you may even learn about something that will save your model (or skin).
Hitec Aurora 9 Fail-Safe Setup
a. Switch on the transmitter, then the receiver, wait for the system to boot and you have control over the model.
b. Press and hold the receiver function button for 6 seconds, release the button. After 2 more seconds both red and blue LED’s blink rapidly.
c. From the moment you release the button, the receiver will count 5 seconds during that time move all the transmitter sticks and other controls to the desired Fail-Safe positions (e.g. motor idle, control surfaces neutral) and hold them there.
d. After 5 seconds the system will save the Fail-Safe position. Relax all the control sticks.
e. Turn off the receiver, then the transmitter.
f. Turn on the system to use it. Fail-Safe is now activated.
Testing the Fail-Safe setting
a. Move the sticks to positions other than the Fail-Safe settings, and then switch off the transmitter. he servos should now move to the Fail-Safe positions previously stored, after the HOLD period (1 sec) has elapsed.
SETTING THE FAILSAFE Futaba 8FG
The failsafe feature allows you to set the positions to which each control will move
should the radio signal to the model fail or be corrupted. While this may prevent a flyaway
or save the model from serious damage its main purpose is to minimise the risk to
people on the ground.
In 7-channel mode the failsafe is only available on the throttle channel. In the LINKAGE
MENU scroll to FAIL SAFE and tap RTN. You will see that, by default, the throttle is set to
HOLD . This means that the receiver will hold the throttle at whatever
setting it is on when the radio signal fails. It is strongly recommended that this should be
Scroll to HOLD next to Throttle and tap RTN. Scroll to
change HOLD to F/S and confirm with RTN. A % value
will now appear which shows the POSition to which
the throttle will move in the event of signal failure.
Scroll to this value. Move the throttle stick to its fully closed position and hold RTN for a second. The value
will change to reflect the position of the stick.
Check the operation by switching on the receiver.
Open the throttle by moving the throttle stick up.
While watching the throttle servo switch off the
transmitter. The throttle servo should move to its tick over position. Switch on the
transmitter again and the throttle servo should return to its original position. On an
electric model the motor should stop when the failsafe activates.
In MULT and MLT2 frequency modes failsafe positions can be set for every channel.
Spektrum Failsafe Settings
three settings really, Smartsafe and failsafe and hold last command
SmartSafe™ prevents unexpected motor startup when connecting the battery and shuts off the motor if the signal is lost. Failsafe positions for all channels are stored during binding. If the receiver is turned on before the transmitter, the receiver will not output a signal to the throttle channel, preventing the ESC from arming. When the transmitter is turned on and the throttle is placed in the low throttle position, the receiver transmits a low throttle signal to the throttle channel, allowing the speed control to arm. After connection, if the signal is lost, the throttle will go to its preset failsafe position (low throttle), while all other channels will hold their last command.
Preset Failsafe The Preset failsafe moves all channels to their programmed failsafe positions. We recommend using Preset failsafe to deploy spoilers on sailplanes to prevent a flyaway if the radio signal is lost.
To program Preset failsafe:
1. Insert the bind plug in the bind port on the receiver and power on the receiver. 2. Remove the bind plug when the orange LED on the main receiver and all attached remote receivers flash rapidly. The orange receiver LEDs will continue flashing.
3. Move the transmitter control sticks and switches to the desired Preset failsafe position. Power the transmitter on.
4. Failsafe programming is complete when the orange LEDs on the transmitter and all receivers turn solid.
The Hold Last Command failsafe maintains the last command on all channels except throttle. If the radio signal is lost, the aircraft maintains the commanded heading until the receiver regains signal. To program Hold Last Command, follow the provided binding instructions in the instruction manual.
To Test Hold Last Command:
1. Power on the transmitter and receiver.
2. Move one of the control sticks to the desired Hold Last Command position and hold the input.
3. While holding the control input (for example, a small amount of rudder) power off the transmitter. The rudder should maintain the input command
– Peter Rebbechi … [email protected]