turns

I just built a new quad with a spracingf3 flight controller and I have a problem where motor 1 will randomly turn off when i give it power... , I have checked all solder connections... I have tried to flash cleanflight firmware to try to fix it but it says lost connection, and something about...

Hey everyone, I have been wondering about this for a few days now: What do planes use their rudder for when they have ailerons? I understand that 3D planes need rudder for their awesome crazyness, but what do 'normal' planes use it for? A plane can turn using it's ailerons right? Or can only...