Sailplane Tow Hooks, Nov 2018

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There’s a number of tow hooks available for RC Sailplanes. I often find myself using some of these and some of the 2M planes being kitted from Europe offer some other interesting methods. As long as it’s simple, secure and robust it should work

Sometimes I see simple L shaped screw in brass hooks

Then there are the serrated bed hooks which seem to be infinitely adjustable and held in place with the mirrored serration like seen on a lot of F3J Models

Airtronics supplied in their kits a nice aluminum rail with hook and screws that worked very well, and in most cases appeared too be twice as long as needed If mounted correctly

The simple brass with wood , L shaped hooks were simple, too rudimentary for me though, as you need some wood around the thread to hold the hook thus making more accurate adjustment difficult, especially for those that are more particular


an older releasable hook, the upper lever when pulled forward allows the hook on the underside to pivot down and release the ring. These are often found on older planes, personally I wouldn’t trust the strength of these old plastics 🙂


Captive releasable tow hook popular perhaps 20 – 30 years ago, that had a arm from a servo to release the ring/ tow line


These are aftermarket tow hooks, the principle similar to that of the airtronics assemblies. The hook is slightly over 4 mm diameter and the channel is 3/4 inch wide. I like the length of these however find the proportions don’t fit for 120 inch and under wingspan planes. I also just notice the slot is wider then the width of the upper nut, so as one turns the hook itself  the top nut can turn.


I really like these smaller tow hooks, perhaps these are from the Ukraine


Here again the Standard Airtronics hook assembly


L hook, with screw in piece of spruce and lite ply load spreader


This is something I have been doing for quite a while now using 3 or 4 MM hooks The slot in the fuse bottom is sized for the hook a spreader plate fashioned from aluminum is on the underside with a tracking screw so the plate doesn’t turn Above inside the fuse is a spreader plate made from 1/8 aircraft ply, not the Lite PLy, with a slot to suite the size of the barrel of a T-Nut that fits the hook thread. These slots perhaps 1 ” long are located under the CG location, perhaps starting 1/4 inch forward of the indicated CG. The 3/4 ” movement rearward I have found has been suitable for my flying style and Launches.


Here’s a view of the inside of an Elio fuselage showing the spreader plate and t- nut. Simply loosing the nut on the underside allows adjustment of this hook


This is some of the hardware kit Airtronics supplied in there older kits the hook and aluminum bar can be seen on the right. A slot is cut in the center bottom of the fuse, and the aluminum extrusion is located for and aft below the CG. The nut on the hook was keep from rotating on the underside by the width of the slot and the hook could be located and locked anywhere along the length of the slot


Crosspieces and spacers are needed to locate the assembly and spread the load thru to the airframe


If you watch closely sometimes you can find these like new Tow Hooks , awesome


These hooks have a curved base the hook diameter perhaps 4 to 5 mm and work well in the larger more modern ships. These are very robust and I believe are available in two sizes . The smaller ones are pictured above


Tow hook assembly with crosspieces ready for a newly built Sagitta 900

4mm-hook 3-mm-tow-hook Aquila Grande