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  • Tow line recovery

    At every aerotow, tow lines get lost. Either dumped to preserve the tug and or glider, or they break away. Seldom does anyone ever see the lines descend. We have had some issues with our tow lines being "found" by the farmers machinery in corn or bean fields. A tow line wrapped around a moving shaft, gathers strength every time it's wrapped and can cause damage in the thousands of dollars to the farmer. A bearing for a John Deere combine can come with a big price tag.

    Our club has been working on some small devices used by falconers to help locate wayward birds that allows you to track the bird. The devices are very small and can easily be attached to a tow line. We could track the line using a locator. Since these devices are strapped to a birds leg, they are very lightweight and can handle being tossed around a bit.

    In the mean time, we have taken small tough parachutes, like the ones used on the end of a winch, and have studied putting them inline with the tow line. Yesterday, we tested out the theory. We placed the parachute about 2 feet aft of the tow planes tail. The parachute is facing the same direction of the tugs so that it won't open while towing. I flew my tow plane yesterday to about 200 feet and released. My spotter could easily watch the tow line descend to the ground, and recover the line. The winds were light so I was able to drop the line right on the runway.

    A second flight, I flew to about 400 feet and released. I was able to complete my landing pattern, land and shut the plane down and still watch the descent of the tow line. The line drifted a little more than the first attempt and landed in a tree but I would rather have a line in a tree than in a farmers combine.

    This system is obviously not going to be fool proof. Lines will drift and could cause the lines to drop vertical and pile into a small area. But at least the brightly colored parachute would make visual recovery a little easier. The parachute might lay on top of corn or beans making spotting easier.There is also the case where the tow plane releases because the glider cannot release. But, I don't think the parachute would give enough resistance to the glider to make it un flyable.

    Just some ideas of others are facing the same issues of not wanting to become an enemy of nearby farmers.

    --Tim

  • #2
    Maybe a better option would to use a F3J/F3B chute..alot smaller but should give the same result..I have a few as I practice F3J quite a bit and I can bring a couple to Sled where we could try out if you like.

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    • #3
      Pretty good ideas! Theoretically speaking, if there is any breeze then the tow line should 'lay out' in the wind direction increasing the chance of recovery. Bow string silencers (archery item) might be useful on the tow plane end, too. Enough of them could slow the descent. They come in bright colors, too!

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      • #4

        Thanks Tim and Mike...Would love to borrow a few of the smaller chutes JIm, and I have no idea what a Bow String Silencer is but will try to find some...
        Saving flying fields has to be a very high priority for us...

        Comment


        • ARUP
          ARUP commented
          Editing a comment
          Kevin- just Google 'bow string silencers' and click the 'images' tab. Some look like fuzzy Tribbles of Star Trek fame and others look like spiders of sorts. There are many variations upon a theme, naturally. They weigh nothing and would hardly affect tow plane performance, come in may colors and are easy to install. What is nice is that enough of them on tow plane end would act just like a parachute.

      • #5
        I'll chime in some ideas.
        When I used to tow full size gliders we put a plastic wiffle ball on the glider end of the tow line mainly to help keep the end of the line higher as our glider field ended at an interstate and we didn't want to drag our tow hook across someones windshield and it helps spot the end of the line to hook up the next plane. In flight it made it easier to see the tow line as well. I thought about putting a large styrofoam ball on the end of our scale towlines but don't think it would last very long. Those large plastic wiffle balls are fairly inexpensive and don't weight much so that may be an option.
        Our local tow pilot ties a wad of fabric streamers about 2/3 back from the tow plane just for his own towline reference so he can see it in the air and they also help the line ride a little higher on approach so he has better runway end clearance.

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        • #6
          Good topic, Tim. I talked at length with Mark at HH Aerotow about his towline winder. I think that is a great option but the idea of a ‘chute, bow silencers or Bryan’s waffle balls are great ideas. I’ve had property owners “demand” lost towlines be recovered and the reasons you enumerated are obvious. Good stuff........

          Comment


          • MarkRobbins
            MarkRobbins commented
            Editing a comment
            yes, but I'm still going to dump the glider if that means saving the tow plane. I don't think the winder will make a difference on occasions when the lines get lost.

        • #7
          Thanks all..the tow line rewinder is perfect to reduce tow line snagging and crashing on landing but adds nothing to the lost tow lines at height, which regardless of set up...releases the 100 foot of line at a thousand feet and it is next to impossible to see where it lands. We are pursuing all the suggestions as well as parachute and GPS tracking devices...we spent nearly 90 minutes at HH aero tow looking for a line in the beans and never found it. In corn even more impossible...
          Really hoping this pans out and can share what works and what doesn't at SLed Works in a few weeks....we can't afford to lose any more flying fields !!!

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          • #8
            What BryanB said is what we do at our full scale soaring club. I have been using neon ping pong balls. Now commonly known as beer pong balls.
            Now take this one step further and mount a Marco Polo "dog tracker" device into an elongated ping pong ball and if the line got lost you can track it with a hand held device. The device is small and light weight... Maybe Jeff D. Can chime in with more details and some pictures of the said device.
            Gunny
            Aviation Concepts rc

            Comment


            • ARUP
              ARUP commented
              Editing a comment
              Ping pong balls work great but I remember poor Al Clark's tow line... somebody stepped on the ping pong ball and he didn't have a replacement.

          • #9
            I currently use a shuttlecock on the end of the tow line, it helps hold the line high and also protects the snap hook once on the ground, I just drill a hole thru the end and thread it on before the snap hook, it can slide on the line so when attaching to the glider, just slide it up a bit hook to attach the glider, Works well and can be seen when released. I do like the parachute idea placed just behind the tug. I'll try this option also.

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            • #10
              I remember seeing these before. Found an image of them in fluorescent plastic. Don't know how they would work and these are white, but a can of paint could fix that.

              https://www.academy.com/shop/pdp/tou...dCatid=5252756

              Smaller (scale) version of what BryanB mentioned.
              Mark

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              • #11
                I like the shuttlecock idea but maybe make a simple plastic cone pop riveted or stapled together? Use a day glow color and make it around 8-10 inches in diameter? Polyvinyl or Polyethylene? Something tough but flexible.

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                • #12
                  Brilliant BryanB

                  I did something like that 10 years ego.
                  I have used Falconry Tx and plastic cone to house it
                  These TX were popular to use in glider clubs. We had transmitters in the models. Club had an Expensive Rx Locator
                  cone was made of white 1/32" ABS
                  Cone alone had specific performance
                  If CG was low and attachment point in the front bottom (like on picture)
                  cone was getting angle of attack and actually lifted end the of rope significantly during the flight and landing
                  I did not have a chance to fly this set up for long and give more experiments ( like sweet attachment point) a try. I have crashed my Pegasus due to aileron reversal on RC TX (2007)

                  and Hey
                  I still got that towing rope winder (retriever ) to finish
                  anybody interested?

                  Mike

                  Comment


                  • BryanB
                    BryanB commented
                    Editing a comment
                    There you go! As the saying goes..."There's nothing new under the sun!"....just updated technology....

                • #14
                  It is definitely a "go".
                  At least for me
                  you can trim it to desired size and shape.
                  it would make our ropes fly high
                  I will probably put that perforated white ball in the nose to prevent grass and dirt getting caught inside
                  ordered both
                  Thanks for an inspiration

                  Mike

                  Comment


                  • #15
                    We received the stuff from Marshall...the transmitters are really small...Larry plans to thread their antennae up into the Neon Pink Paracord and then heat shrink the actual unit and place inside the orange golf whiffle balls that I found at Target....got the yellow cones suggested...not sure yet if that will be too much drag though...especially through corn etc...
                    Will be putting it all into motion a week from today at Sled Works Aero Tow...have small parachutes on each tow line as well...
                    wish us luck.
                    kevin

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