Launching challenges

Catapult bungee setup for launch

Launching wings has been a bit hit and miss for me, until I got my confidence I would often get a wing over and cartwheel them into the ground. Because of these past experiences I was quite nervous about following up on Stu's successful first launch of the Skywalker X5. Developing a system for launching it reliably by myself I knew was going to be a challenge and may possibly involve a few crashes.

I had a bungee catapult in the cupboard so thought it could be a way of getting airborne with the least amount of heartache. The thing with bungee catapults is that they help to give a more consistent launch, something that hand launching is not known for.

So Harry and I built it in the morning (didn't take long) and tested it on the back lawn. I loaded the bungee about half way, connected the X5 to it and got Harry to trigger the foot pedal on my command. The very first time we did it Harry got a little overzealous and stomped on the foot pedal as soon as I asked him to come over and get ready, lucky for me the bungee barely had enough in it to get the X5 off the frame and it flopped onto the grass unharmed. the couple of tests were a little more controlled and we got it to launch a metre or so into my open arms (very serious wicket keeper pose).

With initial tests complete we headed to the Woodbridge flying field for the real deal. It was 32 degrees, the wind was E/SE 19km/h gusting to 27km/h so we had a nice breeze to head into.
The bungee catapult launches were not that successful, all of them resulted in wing overs and one with the X5 doing three cartwheels over the grass, the only saving grace was that I had the wisdom to make them all no-power launches so the inertia was low.

Fed up the bungee catapult I decided to give the old hand launch a crack. Again I decided a few power off glide tests would be prudent before trying a full power launch. The first attempt resulted in a mild right hand wing over but I just managed to recover. I trimmed the aileron and tried again, success! Three more just to make sure I had the right system and all was looking good. I then went the 3/4 power hand launch and she went off like a dream.

She climbed quite quickly and I noticed that the up elevator I had set last week was too much as I could barely make her fly level. I gave her full down trim and the Skywalker X5 felt much better. I flew a couple more circuits, flying across in front of me where I could see how she was responding. Trimmed her up a little more and other than being bounced around a bit by the wind was happy with the end result. I'll now make the current trims permanent mechanical trims and put the Tx trims back to neutral.

It was an excellent flying session and I'm very pleased with what I have learnt. I was really hoping I would be able to reliably launch the X5 without a bungee catapult, for such a small airframe I thought it was going to be a shame to have to lug all the extra gear around. So I'm happy that the catapult didn't work for me but the hand held launching did. The catapult can go back in the cupboard and may come out when I get a much larger airframe to launch.

The next step is to continue to work on perfecting the hand held launch, confirm that the latest settings give a stable flight and practice landings. Hopefully I can get back to the field this week for a good 30min flight of simply taking off, flying a circuit or two then landing and repeating that process over and over again.