Irresponsive Controls! Failsafe triggered! Apm

Hi guys!!! I was flying with my drone the other day and I lost control of it. It started drifting sideways and going down and the controls became irresponsive. When I checked the apm the red light was blinking as if it had lost radio bind.

I tried flying it low again and as soon as I took off it triggered failsafe.

Here was the first Error for it. Does anyone know what this means?

and this was the second,

Log File C:\Users\renat\OneDrive\Documents\Mission Planner\logs\QUADROTOR\1\2018-04-15 13-52-48.log
Size (kb) 195.06640625
No of lines 2912
Duration 0:01:03
Vehicletype ArduCopter
Firmware Version V3.2.1
Firmware Hash 36b405fb
Hardware Type
Free Mem 0
Skipped Lines 0
Test: Autotune = UNKNOWN - No ATUN log data
Test: Brownout = GOOD -
Test: Compass = GOOD - No MAG data, unable to test mag_field interference

Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERR found: FS_THR
Test: GPS = GOOD -
Test: IMU Mismatch = UNKNOWN - No IMU log data
Test: Motor Balance = UNKNOWN -
Test: NaNs = GOOD -
Test: OpticalFlow = FAIL - ‘FLOW_FXSCALER’ not found
Test: Parameters = GOOD -
Test: PM = GOOD -
Test: Pitch/Roll = FAIL - Roll (-152.71, line 1982) > maximum lean angle (45.00)
Test: Thrust = GOOD -
Test: VCC = FAIL - VCC below minimum of 4.6v (4.505v)

I appreciate any help! Thank you in advance

You will need to post a log file from the FC for anyone to more than guess at the problem.

My bad Mike, here is the link for logs:

Thank you for your time.

As the report says you had a FS:Throttle event, in other words you lost radio.

As you don’t have your voltage and current configured, and the loging is at a bare minimum, that is about all that I can glean from the logs.
Here you can see the event against RCin.

Check your radio setup, that seems to be the problem area.

I agree. Radio failsafe with no attempt to either RTL or Land.

My next question is what brand and model of radio do you have?

Thank you guys for the help. My radio is the Flysky Th9x with a R9b receiver.

Could it also be something related to wiring with the apm? Or should I just set the radio up again?

The TH9X is a half decent radio, but I don’t trust the stock TX module or receiver. One of the things I don’t like about the stock TX and RX is that even though Fail Safe is listed in one of the Setup/Menu options in the radio, the stock RX does not have any fail safe functionality. BTDT…

The only way I know of to get a working fail safe is to upgrade to a FrSky XJT TX module and a compatible receiver like an X8R, X6R, etc.

This, coupled with the fact that the TH9X does not support flexible switch/knob channel assignments is why I bought a Taranis.

With that said, you need to make sure the receiver antenna is not being blocked or shaded by any carbon fiber and do a range check before each flight…

I will try and do that, it seems like the flysky th9x has been having a lot of signal problems.

The FrSky XJT TX may be the solution in this case!

Thank you all for taking your time to help me!

If you change the TX module you also have to change the receiver.