There have been discussions before calling for reliable and accurate alternatives to GPS. The Vikings may have had the answer without knowing the physics. They were adept navigators at latitudes where frequent cloudiness and low sun angle(winter) could have made direct observation of the sun difficult. Legend has it that they had a magic stone, called a…

Here's the plane I will install my Arduimu and Ardupilot(legacy) into.  I still need to build a motor mount and wind the motor.  It should be stable as it is based on a previous version which was very stable.  I'm aiming for 10-12 ounces AUW and around…