Keep all your fingers with the new Betaflight 3.2 pre-arm feature!

Keep all your fingers with the new Betaflight 3.2 pre-arm feature!

Posted by Jaxon on 3rd Oct 2017

Betaflight 3.2 is the latest update to one of the most popular versions of flight controller software. It introduces a lot of features for smoother flight, and brings a lot of hidden commands out to the surface for everyone. One of my favorite features though, is Prearm. It's basically a way to arm your quads with two switches, which is far safer than just one. In this blog I'm going to explain it's benefits, and how to set it up. Let's gooooo!

For a long time, it's been popular to set up logic switches in your radio as a kind of two switch arming technique. The way to do this is basically tell your radio to not let a switch be registered until an additional switch has been flipped. Radios usually have a momentary switch that goes back to it's original position when you're not holding it. That is the switch that is used for this type of arming the most.

Now, the logic switch setup can be complicated, and if you do it wrong, it can be a little dangerous too. That's why I'm stoked for this Prearm feature! It works the same, and it's easy to setup! I'll use some screeshots to show you how.

You'll need the Betaflight 3.2.1 GUI, or if you can get the 3.2.2 beta GUI, that'll be even better. But 3.2.1 is fine for this.

You'll also need to be running betaflight 3.2. Joshua Bardwell (Of course) has made an awesome guide on getting the new firmware, and I'll link it here for you.

If your FC doesn't power your receiver through USB, you should take your props off if you're playing around with arming!

What you have to do now, is go to the receivers tab. Find the AUX channel of the switch you want as Prearm. Mine is AUX 2, because that's my momentary switch.

After that, you'll go to your mode tab, scroll all the way to the bottom and you'll see "PREARM". Drag the bar to where your AUX channel is activated, and you're all set! 

So now you're setup for safer arming, without having to mess around with logic switches! 

One thing to keep in mind, is how many AUX channels you use. You don't want to have more than 8 switches being used in betaflight because it can add latency, so if prearm is on your 9th switch, maybe consider moving some switch functions to share on a 3 position switch or something like that. Get all the features, without adding latency!

Thanks for reading! I hope this can help some of you out there!