Do you fly a FUTABA 9 ZAP Tx G? I have observed the following:
You know how when you turn the Tx on, it takes a few seconds to go through the "BOOT UP". Well, I used to get impatient and just hit the little "END" button. With both of my 9 ZAPs, if you have Fail Safe activated, and you don't let the Tx boot up undisturbed, the fail safe may not function. It seems that the Tx must boot up undisturbed to implement the FS, or it is at the beginning of the signal that it lets the Rx know what the FS settings are. I am not sure. What ever Tx you have try this test. Turn on Tx and hit the END button immediately to go to the menus. Turn on Rx and put the sticks in a corner and turn Tx off.... will your system go to FS? My system sometimes will... and sometimes wont.... usually not. I have had 100% success if I turn the Rx on first, then turn on the Tx and let it boot up undisturbed. I check this at the end of each flight by "Boxing the sticks" and then shutting Tx off... and watch plane for Control Surface response..... Is this a documented issue with FUTABA?