UAV Flight Training, Round 1

A few months ago, I mentioned that my friend and I were going to start building a UAV. It’s taken us a little while, but I’m pleased to report that over the previous bank holiday weekend we were able to take it out for our first test flight.

This test flight was the first step in our move towards building a fully automated UAV platform using a Netduino. This flight, however, is 100% manual, with no auto-pilot assistance. The objective is to get to grips with manual flight as we need to be able to launch and land the aircraft and take over in the event of an autopilot failure.

Now, bearing in mind that neither of us have any flight experience whatsoever, below is a video clip of some of the flights during the day. There are, as you might expect, several crashes and some very unsettling flight patterns, but don’t worry, as neither I nor anybody else involved have any aspirations to become a commercial pilot. 🙂


Lessons learned

As the pilot, I gleaned some useful insight into the flight characteristics of the platform. Here are my initial thoughts:

  • The stock rudder is way too small to have any authority, particularly with the upgraded brushless motor. It has a control surface of just 2.5cm x 10cm (approx.). In light wind, it was pretty much uncontrollable and at speed, no chance. We later modified the rudder to 6cm x 15cm and are looking forward to testing that out next weekend.
  • After the first crash, the tail completely detached from the body. It was way too brittle and broke in the only place we hadn’t reinforced with glass tape. After fixing, we ended up with a plane that was, well, a bit ‘warped’. That’s fine for our trainer, but in a future version before we integrate the UAV electronics we’ll probably need to embed some carbon-fibre rods throughout the body to improve the rigidity.
  • Ailerons would make the model much more responsive, so we’ve added those too (I’ll probably blog about the modifications in a separate post) and these will be tested next weekend.
  • We should have taken time to balance the centre of gravity properly. This might account for some of the more ‘wild’ elevator action seen in some of the clips.
  • Even when flying into a headwind, very little motor input is required in order to maintain stable flight. I think I only used 100% throttle maybe once, just to see how it reacted.