In this tutorial I will guide trough the steps for scratchbuilding a freeflight glider, powered by a HiStart
Step 1: What Is a HiStart?
A HiStart uses the combination of a elastic tube attached to some chord and them eventually to the aircraft's nose hook. You should have about 25% elastic tubing and 75% Nylon. As elastic tubing I used Thera-band, widely available in Europe and America. Make sure you choose the right strength for the aircraft you want to launch. I used the blue one, which worked fine for my glider. The connection links are established by keychain rings you can almost find anywhere. So once you have all that, you can shoot almost any plane in the skies
Step 2: Starting With the Glider: Wings
I used foamboard to create my wings, I won't put any plans up here, because it's a more personal choice, to choose the wing you want, if you take a quick look on the internet you will find loads of plans en wing profiles, suited for your type of flying. My wing has a wingspan of 1m40, which is wide enough to go stable on the HiStart.
Remember, if you choose to use smal wings, the chances of your aircraft tiping over during launch are way higher. It isn't suited for gliding as well. I have also put an angle on the wingtips to make the wings polyhydral, which will give you better flight performances and glide ratios. It's important you make everything very precise, because imperfections can make the glider become unbalanced, which gives you more work. Also precision working will reward you in flight times
Step 3: Fuselage
I used 20mm thick balsa wood to create a massive fuselage . A jigsaw has been used to make fast and clean cuts in the balsa, I used a chisel to make space for later weights when balancing the plane before flying. I had to put 4 used batteries in the fuselage to make it balanced, for a total of 80g, Which was quite a lot, but the wing was also way more to the front. You can also see that a hook has been attached for the HiStart, make sure it is located in front of the CG (centre of gravity) which is generally at 30% of the wing. After this has all been done, it was time for glueing, the carbon tube was attached with the hot glue pistol, the fuselage with ordinary wood glue.
Step 4: Cutting Carbon Fibre
First, to protect yourself use a mask with a filter, as there are fine dustparticles coming free when cutting carbon fibre, I also strongly recommend to put some gloves on, as you can be hurt by sharp edges, and the fines dust particles can be irritating on your skin. Make sure you put a small cut around before cutting it in half, if you don't do this, chances are you will be disintegrating the fibres and thus, losing strength.
I made a simple tail for the glider, this has been a redesign using 3mm foamboard, because the other tail was to heavy. Notice that I made groove, the enlarge the contact surface with the carbon fibre tube, this will improve strength.
Step 6: Attaching the Wings to the Fuselage
I used simple rubbers to attach the wings, to 2 carbon tube left-overs in the fuselage. First you make a cross pattern and then the same side over.
Step 7: Maiden Voyage
Now it's time to let it fly. First make sure your plane is well balanced by checking it with hand launches.
Once it's balanced you can hook up your glider to the histart.
You hold the Nylon in your one hand and the plane in the other one, when you feel it's firm enough, you hook up the glider and throw it in a 30° angle. Now you can see it fly and enjoy the view of it. If you feel comfortable you can stretch the rubber even further and have higher altitudes to play with
If you have any questions, feel free to ask