Tug conversion
 

hi everyone

im currently bulding 3 Mam'selle 52's (all in different stages of completion) and was wanting to turn one into a glider tug.

its designed to run on anything from .090 to .15 two stroke glow (im running an OS MAX .15 on my first one, turning my other one leccy and the tug will probs be glow aswell) the plan is designed for a 3ch with dihedral, but ive flattened out the wings and added dual ailerons to my first one, i may do the same on the tug for more control

any ideas/photos of your conversions are welcome

RE: Tug conversion
 

I would STRONGLY recommend ailerons on a tug.

I would also recommend using a larger plane for more dominance over the glider.

Also, it is best to attach the pull string to the top of the wing at the CG. Attaching it to the tail can be disastrous because if the glider rises above the plane (Which they are notorious for doing since they have so much lift) it will pull the tail up - which will force the tug down - which will result in more speed - which will result in the glider producing more lift - etc

With the tow line at the CG, if the glider rises above the plane, it will just lift the tug at the CG

RE: Tug conversion
 

thanks minn, wont the tow line gut in the way of the tail surfaces though?

RE: Tug conversion
 

heres some pics of the first one, btw

http://i57.photobucket.com/albums/g2...y/IMAG0632.jpg
http://i57.photobucket.com/albums/g2...y/IMAG0631.jpg
http://i57.photobucket.com/albums/g2...y/IMAG0630.jpg

RE: Tug conversion
 

No if the glider stays in high tow the entire tow and what is normally done, unlike full scale towing where the glider normally drops into low tow for climb efficiency and the tow pilot does not have to trim exceessive up elevator.

The gliders are far easier to handle in high tow and definately use a topside CG hook on the tow plane. I would also recommend for the glider also to have ailerons, without which at least with two meter or larger gliders severe whipping manges to manifest and lurk around the next circuit. Have tried rudder and elevator only ships and most tows end up wiping so bad that it is difficult to get a lot of altitude because of early releases.

The CG hook also allows the glider to help the tow plane off the water or ground Have done some tow off of water with a powered set of launch floats for the glider that drops off. senario is after the glider reachs around thirty degrees tow angle the addition lift component on the tow plane helps the tow plane up. This was a vital factor in the water tows.

Here is some vidio of the Oxy Moron actually a twin engined Seniorita with quick removable nacelles doing some tows and a photo of the the powered float launch Water Walkers for launching gliders off water:


John


http://video.google.com/videoplay?do...06427302&hl=en

RE: Tug conversion
 

a twin seniorita, quite ingenious...

ive got an old trainer that is probably more suited to towing... hmm... now the ideas are flooding in :P

RE: Tug conversion
 

Here is the home made pelican hook servo actuated along side the nose wheel. The hook is centered and the nosewheel offset to the side.

RE: Tug conversion
 

i dont see any pics... methink something gone wrong? :P

RE: Tug conversion
 

How do you get the glider to release the tow line?

RE: Tug conversion
 

Here is the home made pelican hook servo actuated along side the nose wheel. The hook is centered and the nosewheel offset to the side.

RE: Tug conversion
 

You have to install a releaseable tow hook in the nose of the glider. Also to be ideal, the tug should be able to cut the glider loose as well.

Size is good :D here's the one we've been using.

RE: Tug conversion
 

Actually, there's a better way to do it.

What I did was to build a cradle that mounts to the top of the wing on the tow plane.

The glider sits in the cradle and is held in place by rubber bands.

When you're ready, the rubber bands are released and away goes the glider.

Two big advantages to this system are:

1) you don't have to worry about what position the glider is in (Too High, Too Low, etc)

2) you can use ANY glider - IT doesn't need any type of release mechanism

RE: Tug conversion
 

Piggyback launchs are cool and a lot of fun as well as easier but I would not neccessarily call it a better way. Thats because it does not offer challange and skills that must be acquired with aerotow on both ends of the towline.

Aerotow for those five or six that I have mentored into the technique becomes the whole point of the flight and some will circle down quickly to get in another tow.

Here are some of the wheeled launch dollys I built for the guys using conventional gliders:

RE: Tug conversion
 

Pretty neat! Does that pivot up to allow the rubber bands to snap off? Do you actually tie the bands off so that you don't lose them?

RE: Tug conversion
 

Cradle launch is safe but boring after you've done towing :D

We have been there done that too.

On ours the rubber bands are secured on the back so they just flop around after the glider lets loose.

RE: Tug conversion
 

I've also used both ways and had fun with both, most of mine were before internet and we had to figure it out ourselves which made it even more fun.

I hope Wild Foamy intends using SMALL foamy gliders with his tug. I wouldn't bet on his set up being able to tow much more then foam gliders using only a .15 size engine, or did I read it all wrong ?????
ENJOY !!! RED