Setting Failsafe on Arduplane & Futaba T10CAP
The Problem: Switching my Futaba T10CAP Tx off wasn't engaging RTL on my HKPilot Mega 2.5 controlled Phantom FX-61 flying wing.
The solution: In this plane I'm using the Corona R8FA 2.4GHz Fasst Compatible Receiver for which the manual is found here. The failsafe functions of the APM board are defined here. By starting the APM Planner v2.0.0 and going to 'Initial Setup', 'Failsafe' you can see the values of the PWM signal the Rx sees from the Tx. In my case, at low throttle position I get 1096 value. Switching the Tx off the value jumps up to 1150.
Going into the Basic Menu on my Futaba Tx, then 'F/S' I found channel 3 failsafe was enabled and set to 20% so when the Rx lost signal from the Tx, the throttle was going up.
1.TX-failsafe feature: This method is to set failsafe on the FASST transmitter and has priority (works
on channel 3 only under FASST 7ch mode or on multiple-channels under FASST multi-channel mode)
while the receiver is working on, just like the FUTABA receivers
For the APM Failsafe function to work, I need the value to drop below 1000 (defined by the paramter 'THR_FS_VALUE') so I disabled the channel 3 F/S setting. Now the RX-Failsafe feature (if enabled) value will be set on Channel 3 one second after losing the link to the Tx. The value is set by following the procedure below. To get a value below 1000, I temporarily set the end point on my Tx for channel 3 to 140% which brings the throttle value down to 966. Set the Rx-Failsafe mode (as below) and then restore channel 3 endpoint to 100%.
2.RX-failsafe feature: Turn on FASST transmitter and turn on the CORONA 2.4GHz Spread Spectrum
Receiver, put all the sticks and switches to where give the control inputs you want if the receiver looses
signal and Press the F/S button down for about 5 - 6 seconds while the Green LED light solid (Rx in
normal operation), then release the button. You will see the Red LED will flash for about 4 - 5 seconds.
(Note: The Red LED will FLASH high speed to indicate the RX-failsafe is turned on OR FLASH low
speed to indicate the RX-failsafe is turned off). If you press the F/S button a second time while the Red
LED is flashing, the receiver will change its RX-failsafe status (on / off),then the LED will return to
Green solid again. If you not press the F/S button .Nothing will be changed and the LED will return to
Green solid again. If you want to cancel the RX-failsafe feature (not just turn it off), you can do it by
binding the receiver again.
OrangeRx Futaba FASST won’t centre
Setting up the Seagull Decathlon radio gear showed the twin elevator servos wouldn't centre when the sticks were released. Swapping out the HobbyKing OrangeRx Futaba FASST Compatible 8Ch 2.4Ghz Receiver for a genuine Futaba receiver showed that the problem wasn't with the servos as the genuine Futaba Rx worked fine. By default the HobbyKing FASST receivers are set to HS Mode for digital high speed servos which is not so great for the analog servos in the Decathlon. The Frsky manual shows how to change between the modes as does this YouTube video.
Inside the eHawk 1500
The eHawk is about ready to maiden. Inside the fuse I have a JR RS70 receiver velcroed to the side of the fuse, a HobbyKing 15-18A ESC to the other side and a Turnigy 1200mAh 3S Lipo in the middle with velcro on the bottom. I haven't checked the CG yet but it looks like I should be able to move the battery back and forth pretty easily. The trusty old Futaba FF7 36Mhz transmitter will provide control. I included pics of the Futaba Tx and JR Rx just because some people don't know that the two brands will happily work together. Why did I buy the JR Rx if I was using the Futaba Tx? Probably because the Futaba Rxs were too expensive (not that the JR was chickenfeed either).
