Funny Story - Glider Tow

I flew my Fly'n King with a banner last week. Boy, did it work great. The tow point recommended by Bruce Tharp was perfect, right behind the
trailing edge of the wing, centered on the fuselage. I made the banner according to the design on Allen Tong's website, worked the first time.
We also towed a TT Windstar glider with less than desirable results. It was very funny. I piloted the FK and my buddy flew the glider. All went well until the first turn, then the glider started to buck like a mad horse. All kinds of slack got in the line and it just got more pronounced the longer we flew. The glider is an old beater, so I did not care if it did not survive. We had a length of surgical tubing in the tow line, but it did not seem to help very much. My buddy cut it loose and glided back to safety. I dropped the tow line over the runway and landed without incident. On the second try another member showed up who had flown full scale tow planes and gliders. He got volunteered to pilot the glider. This flight was far worse than the first flight. The glider eventually bucked so hard it broke the rubber bands holding it's wing on. The wing fluttered to the ground unharmed while I towed the "lawn dart" fuse of the glider all over the friggin field. We were laughing so hard because the glider pilot was still able to "fly" the lawn dart from time to time, and the whole mess looked so funny with the fuse dragging 80 feet below the tow plane. I circled a few times trying to figure what to do next. Finally I dropped the tow line and glider in the tall soft grass on the far side of the runway. It stuck in the soft soil about four inches, totally unharmed.
Wish we had a film of that. I would entitle it, "When Good Planes Go Bad". We are still laughing at ourselves on this one. We might make several darts and create a competitive sport out of this.
Tom
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I've had some good laughs at glider tow attempts as well. One old fellow at our field wanted to try getting his 2m sport glider towed up behind the Sr. Telemaster we were using for tow. He had it equipped with a release mechanism but it had never been used. So we gave it a shot - bearing in mind his sailplane piloting was not going to give Larry Jolly or the like any fits..
Anyway, I tried flying the tow plane as smoothly as I could, but he got so messed up that the glider ended up about 50-60 feet under the towplane, spiralling like a corkscrew. But this was not at an altitude where we figured he could recover it. So since the Sr. Telemaster could be slowed down and horsed around so much I put it in a steep spiral climb at bare minimum airspeed, basically lifting the glider straight up like it was under a helicopter. When we got up 400-500 feet he cut the glider and all was saved.
I think glider tow is one of the most entertaining things I've done in the last little while with R/C aircraft. That and my first adventures with flying off water.
Mike D.

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If I may add some of my info about this... I bet the length of tubing might have been the source of the bucking. I towed with a fuzzy cotton line of about 1/8th inch in size. The elastic/rubberband like tow lines have always caused me trouble.

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No, it was the glider pilot this time...
We used only a short section of strain relief, the rest was heavy monofilament scavenged from a high start. I had towed several gliders up already quite successfully with this setup including the one in question later on. I also towed up the same glider with a Sweet and Low Stik and Senior Kadet at different times. With the Stik I had to fly high angle of attack mode all the way up but it worked okay, the airplane was predictable enough to do that."Was" is due to slicing off the left wing on a distant approach over power lines sometime later - and not seeing the thin wire a few feet above the main lines. Oops.
Mike D.

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Tom Johnson wrote:

Well I dont feel so bad. I have never really had a sucessful tow yet. Lost a few tow lines in the corn. I tried towing a 2 meter glider with no ailerons. Going into the turn it started to do a Dutch roll(?) back and forth. Release at that point. Tried it a few times. Gave up. Bought a glider cradle for the tow plane that mounts above the wing. Took off and at altitude released the glider and it did a few loops .....and out of control inverted. Mabye too fast on the release. Mabye the glider should have ailerons when on a tow rope. ??
jim
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ailerons are a must...when we aero tow large scale gliders, the rudder is disabled from the ailerons. otherwise, the glider will start pulling against the towline, rather than simply correcting roll. as far the cradel, just throttle back and allow the tug to slow down before release. little 2m gliders have a small speed range, and they don't like to go fast.
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throttle back and allow the tug to slow down before release. little 2m gliders

You do not need ailerons on the glider. I flew and towed many a 2, 3 or 4 channel glider/sailplane up with a SIG Kadet and Kaviler, on up to larger sailplanes behind my SIG 1/4 Cub. The key is airspeed management, and avoid overcontroling. Far to many people fly overpowered airplanes and simply do not know how to fly slow. Keep in mind that both the aircraft you have now "tied" together fly at different airspeeds and the tow plane needs to fly slower then normal. We always used a release in the nose of the plane being towed and a line mount or release at the tail of the tow plane. Depending on what we were flying, spoilers open just a tad help a great deal in keeping your tow line taunt. In a simple rudder/elevator set up, gently turn the glider in the opposite direction of the tow plane. As an example, in a right turn, apply slight left rudder pressure on the stick for the aircraft being towed up. Keep in mind all you want to do is keep the line taunt (drag on the line in front of the glider helps also, such as a few pieces of paper ribbon). To much control with the glider will turn the tow planes tail, left or right, up or down provided you have the line attached there and I have had more then one glider jock all most take me to the ground (the reason I had a release in the tail).
Communication between both pilots is also very important. The first few times plan out the flight, even if it`s a straight line out to height and release. A very slow, large, turning climb is best. Match the aircraft up best you can and practice practice practice. What you get in return is a skill not to many have. rick markel
My Model Aircraft Home Page http://hometown.aol.com/aileron37/index.html
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Here I'm talking 2m or slightly larger gliders, but I agree, I've never had any problems towing rudder/elevator gliders up, on the tow plane or glider end - other than, as you mention below, when speed management got out of hand, or one pilot overcontrolled. You learn not to do that pretty quick. Never towed large scale gliders or flown them but I can imagine it may involve greater challenges. Dunno.
Mike D.

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I've had great success toting gliders up on a cradle above my Kadet Senior but always wanted to try a tow line. Where are the bet points for line attacment on the tow plane and or the glider? I would suspect that line attachment on the tow plane would be close to the rear of the main wing at the top of the fuse. My concern is that the line would contact the rudder / stab and cause a problem. Airplanes that I have that I think would work well for tow tugs. Kadet Senior, Saito 80.. Ugly stick 60, Webra .61 1/4 clip wing Cub, Saito 1.20
Most of the gliders my friends have are simple 2 meter but there is one 3meter Bird of Time and several slope gliders.
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When we first used a Kadet Senior for a tow plane, the toughest part was getting the glider to fly as slowly as the tow plane.. versus the more usual other way around! I can;t remember what the glider was, it was a 2m ARF of my buddy's and flew more quickly than a Gentle Lady or the like.
We rigged the tow line right behind the wing root as you suggested below. I can't say for sure it was needed, but what we did was rig a flying wire type arrangement from each stab tip to the top of the rudder, so that the line could, if needed, slip easily from one side to the other. Ideally you would not need this if you kept the glider properly situated relative to the tow plane, but things don't always go as planned do they? Esp. when experimenting.
Of the three aircraft mentioned, one and three would both be great tow planes. Is it an Ugly Stick or the Ultra Stick with flaps? I mentioned before I used my Sweet and Low Stik for a while to tow 2m gliders, but I really did need to keep it right at the bottom of its speed range with nose up and power on. With some flap dialed in on an Ugly/Ultra Stik it should work like a champ with less flying effort. I think you would be doing yourself a favor by tossing a low pitch prop on the nose - 4 or 5 inch pitch.
Slope gliders - hmm, never towed one, but why not? My first instinct would be a cradle, but depending how slowly they like to fly towing should be okay. They might be a candidate for the Ugly Stick if a little more flight speed is needed and you wanted to check it out as a tow plane, but the others should be able to fly fast enough to tow them too. Just a thought.. Maybe someone else has done this.
I've never flown a cradle, maybe I should give that a go.. time for something different again!
Cheers,
Mike D.

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That is all well received info.. I hate loosing an airplane when someone else's experiences can prevent it. My Ugly Stick is a 15 year old model...no flaps like the new sticks have. I put up a few photos on a temp page and attached them to my home site. http://www.flyinglindy.homestead.com/index1.html In the pics you will see my Ugly Stick ,60....1/4 scale Cub ( beside my electirc B-29 ) and a couple of my Kadet senior with 10 year old home made cradle... ( I'm adjusting my glasses in one photo ) You've helped a bunch, I hope you enjoy the shots I put up on the temp page.. http://www.flyinglindy.homestead.com/pictures.html
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FLyinglindy, What's the bird on the wing, that is, the glider in the cradle? mk

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page..
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That "thing" on the cradle is a slope soar / bungee launch machine usually. It belongs to a friend but I don't know the name of the aircraft..I can find out if you are interested. I may see him this weekend. If I can band it to the cradle I'll haul it up. : ) Lots of fun!
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