Towhooks and COG and Mel

Mel

I found this.

It comes from this thread.

http://www.rcgroups.com/forums/showthread.php?t=1105190

Since it is an adjustable tow hook, you don’t even have to worry about where it goes as long as you are more or less centered on the CG. That is precisely due to the fact that your cg, and your tow hook location are not actually related. Whereever you put your tow hook becomes the CG during a launch. In other words, even if your tow hook is one inch behind the CG (Say you balanced your Supra at 90mm from the LE, and the suggested location is around 104mm) If you mounted the tow hook at 104, as long as that is not behind the wings center of pressure, you will get a nice clean stable launch. The tow hook location is the CG during launch. Also, true would be if you had an unflyable CG due to all of your nose weight falling out, your launch would still go fine while under tension. As soon as tension is relaxed or released you would have an unflyable or way tail heavy glider on your hands.

So, use the suggested CG as a guide, center your hook box on that point, install, fly, and adjust. Nothing to it.

Good luck

Mike

5 thoughts on “Towhooks and COG and Mel”

  1. Robert,
    Thank you so much for the info, I see your point while the model is under tension on the bungee then it does not really matter were the hook is as long as it`s not in a stupid position.

    Who is Mike?

    Mel.

    1. All that writing was copied from a thread in a forum. It was written by a man called Mike. Makes sense though doesn’t it. The whole thread is worth reading.

      Robert

    1. To aero tow I would think the tow would have to be from the front centre nose or just below it of the glider being towed, I say this because the glider would need to be “flown” while on the tow, unlike a bungee when you just hang on until the top of the launch.

  2. I have located the c of g for my Sonata, I did this by trial and error the plan shows a c of g point but in glide tests is was found to be to far back so another 10gms of lead added to the nose and the second test proved to be just about right.
    Once the c of g was found I then fitted the tow hook a few millimetres in front of it, the glider was flown from my bungee with no problems at all.
    I had forgotten what it was like flying this way, the model is quite sluggish on the controls because of the slow flight speed, need a thermal or three now.