Pedal launcher video

[Jason T]

This is a pedal launcher that I build from someone else's design. I did have permission to use their design.

In the video I am launching my Turn Left pylon racer. Its getting heavy from all the fuse repair work so this makes the launch a non issue. Even though this video is short I like sharing this stuff because "a picture is worth a 1000 words" so video has to be better.

Jason

http://www.atltaylor.com/files/turnleft_bungee.wmv

[Jason T]

Okay, here is video from a different angle of the first launch. We were experimenting with the bungee tension and it wasn't enough on this launch and I almost lost the Turn Left.

http://www.atltaylor.com/files/TLbungee.wmv

[luc]

lots of torque...
here is mine (in french but with pics and vid)
http://www.geocities.com/lucchev/bungee.htm

[Jason T]

Luc,

Actually, the bad launch was just not enough tension in the bungee.

I have seen your video before. Nice job!

Jason

[luc]

here is a vid of my sokol launch (around 130 mph...)
http://lucchevaillier.free.fr/sokol.mov

[Foamiesrfun]

Originally Posted by luc

here is a vid of my sokol launch (around 130 mph...)
http://lucchevaillier.free.fr/sokol.mov

Dont think the dog was expecting that LOL,those are neat guys.

[fdix]

wow cool vids!
Did you guys some way calculate where to put the bungee hook or is the position not so critical?

[Jason T]

Luc,

Your dog almost keeps up with the launch.

[Jason T]

fdix,

I did not calculate the position of mine. However, I did put it in front of the c/g. I think if you put it too far forward the launcher would have a tendency to pull it toward the ground and too far back (behind the c/g) it would be very squirely on launch.

The position of the hook on my Turn Left was TLAR (that looks about right) based on the above statement. For example, my hook is about 2.5" in front of my c/g and the hook is about 4.5" from the spinner. The TL fuse is pretty long.

Hope that helps. Maybe some others can chime in with how they chose the hook position.

Jason

[luc]

The hook should be around 1/3 from the front of the plane to the CG.
The more aft and the steeper the climb, which is not really needed, as it is not a glider.

[fdix]

Thanks to you both for the info!

[mrstormy]

Gents, where are good places to get info on bungee launching and planes. This looks really cool and I can't believe I hadn't seen this stuff since I started flying three years ago.

Thanks

[RichTheBikeRider]

Hi go to http://www.ezonemag.com/, there are plans to build one or two there also mine is plastic pipe I had a wood one but in wet grass it warped, I added safty stuff to mine when a kid almost got it from a friends launcher. I Lock the peddle and the bungie also make sure the stake is well set. I really like this style cause you can fly alone in safty.
Rich

[Jason T]

Here is another video of the pedal launcher with a little more video of the Turn Left.
http://atltaylor.com/files/TL-08-27-05.wmv (2.3MB)

[RichTheBikeRider]

Looked OK to me like I said the only difference in mine is the rails slide in or out to accommodate landing gear. Our field is dirt and the city won't let us improve it. My hot liner spinner is repolished from landing, I also use carpet tape on the bottom to keep the paint nice.

Rich

[ericthetree]

what diameter is the cord you are using for this launch system? thank you, ericthetree

[RichTheBikeRider]

For small planes 5/16 bungee for larger planes a second bungee set is added note the break is a 1" ID x 1 foot piece of split insulation foam wrapped with duck tape I'll take picks so you can see construction the whole launcher is made from parts you can get from Ace or Home depot, and a drill press and a file.
Rich

[Jason T]

I am not sure what the diameter of my tubing is. Mine came from the tubing in a high-start which I think was 10 pounds tension. We cut two pieces about 20' long to double them up. My Turn Left weighs about 32 oz and it has not problem launching it.

[ericthetree]

Thank you for the quick responses guys. Rich I would very much like to have some pics, I really like the idea of a rail type slide that is adjustable. pic is what I've come up with design wise so far. adjustable rate of ascent. I will probably make slide sides out of 1x2 pine board. Rich how long is the rail on your avatar pic.

[RichTheBikeRider]

OK here are the Pic'sFor the catapult note it's designed for hi and medium stab's, weight up to 30 Oz. or so. You must spike it down in the rear by the release.

Rich

[RichTheBikeRider]

Here is the pic's of my launcher
Rich

[RichTheBikeRider]

here is a pic of Zigi note the dammage you get when friends use the catapult and wiggle the ailerons in the catapult.
Rich

[RichTheBikeRider]

OK I am going to give you a few pointers on the Catapult.
There are 1-1/2x1/8x8 aluminum under the plywood for strength. The arms that fit over the wing are for anti-blowback.
You need thick enough foam tape to prevent the ailerons on your plane from hitting the back of the launch box.
I keep the square tube lubed with pledge.
note the "Y" for the front legs could be made as a "U" instead. If I can awnser anyother questions just ask.
Rich

[ericthetree]

thanks Rich, I like this design,I don't have any flying partners so I am in need of a launch mechanism.

[luc]

look also at the ez one I use (in french, but includes pics and vid)
http://www.geocities.com/lucchev/bungee.htm