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Failsafe notes (Old)


This document is deprecated, and is not being updated

It is kept for historical reasons only.

Do not rely on any information presented here.

Test failsafe without propellers. Arm the Quadcopter and shut the radio off. Full range receiver and Satellite behave diffently from brand to brand, read the operator's manual.

What is a failsafe?

Failsafe is a safety feature, it can be triggered by a switch, the loss of radio link or an unexpected RCcommand pulse. The flight controller will behave as set in the failsafe tab of the configurator. (Betaflight's default = Drop). Once configured, specific Failsafe behavior can be changed before flight. See the Betaflight GPS Rescue Mode page.

Why should I set my Failsafe?

Failsafe places the flight controller in a "safer" state. Typically, a small quadcopter can fall without severe damage but with bigger quads, it might be better to land. The basic rule: it is better to drop from the sky unarmed than have a flyaway, randomly chasing people.

You might want to set the RCcommand on failsafe for each channel. I usually set throttle to hold leaving pitch, roll and yaw to "auto". Auxilliary 1 switch to "unarmed", for me it is "set 1000" and AUX 2 "set 2000" ( I have a mini-Quad with a beeper which makes it easier to locate).

-Enable Expert Mode Failsafe Tab

Mode Tab

I leave throttle to "hold" for 0.4 second in the configurator tab, I can live with that. After 0.4s, the FC will put the RCcommand to the rx failsafe set value. This is why it is so important on binding process to have the correct stick position. You might feel anxious about it and uses auto, in this case the RCcommand set will be the one stored on binding of the receiver with no delay.

What can cause failsafes?

  • RX Signal out of range
  • Broken, damaged or not the right length antenna on RX and or TX
  • shadowing, multipathing, antenna conductor touching carbon fiber or signal blocked by carbon fiber
  • Too close of the VTX
  • With satelite, 3.3v regulator problem on FC
  • Broken or loose wire
  • Cold solder joint

Stage 1 and Stage 2

Basic Setups and Knowledge + Different Failsafe behavior

Quick and dirty troubleshoot: