What weight of tow loop line to use

[Hoot]

I've searched the Scale soaring site regarding tow loops but need to have an idea of what weight of braided line to use for a Baudis Diana 2. The plane should weigh approximately 18 to 20 pounds ready to fly. Knowing the tow loop is the weak link, I don't want a tow loop that is too strong or too weak. Are there guidelines for the weight of the tow loop material versus the weight of the sailplane?
Thanks !

[BryanB]

On the Front page there is a section about tow lines.

https://www.scalesoaring.com/how-to-make-a-tow-line

I think most of us just use the braided seine twine #30 and keep our finger on the trigger of the release.

BB

[Steve P]

Hi Hoot. Braided mason’s line will do the trick.

The “weak link” concept is more myth of days gone by than a practicable application. A bad name for the loop that speeds up sailplane pilots being able to attach their birds to the towline.

Hence, why both tow plane and sailplane must have functioning releases. Sizing a loop to be strong enough not to fail on initial tow acceleration or early in the tow at low altitude but not too strong that it couldn’t be forcibly broken with intent or out of control would demand a different loop for each sailplane, sailplane-towplane combo, wind conditions, tow speeds, etc. The theory that if all goes to $#!+ at altitude the loop will save the day is hope, not a strategy. Communication actively between both pilots throughout the tow is key, as is a willingness to let go if a tow begins to go bad. Combined tow plane and sailplane simultaneous release failures is an infinitesimally slight chance. When there is a “I can’t release” it has more to do with line tension, crappy servo and the opportunity for the tow pilot to throttle back. Again, communication prevents a world of issues.

Now, what we DO see is cheap, weak, slow to release servos employed by some sailplane pilots making every tow an adventure as they simply cannot release even a rather standard tow. We suggest alternatives and fixes and if they show up the next event not having solved the issue ... verbally humiliate those folks. ;-)

Braded NOT twisted line is key as it is much easier to insert. Mason’s twine, etc. all work well. Some us us fly 40lb+ sailplanes using much heavier stock. Just be certain when you walk out to the runway make your loop is in place and ready to tow and all will be well.

[Hoot]

Thanks for the recommendations on tow loops !