Aerotow towrope instructions

I should have added, we also install a "Whiffle" ball (lots of holes) on the glider end to protect the tow ring and also have a short length of clear plastic tubing (couple of feet more or less) that covers the poly rope. This clear tubing slides easily on the rope so it can be inspected.

Tom

On Wednesday, April 6, 2016 at 6:39:33 AM UTC-4, wrote:
I should have added, we also install a "Whiffle" ball (lots of holes) on the glider end to protect the tow ring and also have a short length of clear plastic tubing (couple of feet more or less) that covers the poly rope. This clear tubing slides easily on the rope so it can be inspected.

Tom

Tom,

Is there an ideal location of the whiffle ball? When I saw your comment I got to thinking if there is an ideal distance from the tow ring. Our club has one on out tow rope but I have not measured the location of it.

I was speaking to someone a few weeks ago about tow ropes and they also use plastic tubing in the loop splice. But after cutting the tubing they melt the sharp edges to round them over with a soldering iron to prevent the tubing from chaffing the line.

Speaking of weak links: I was given some glider gear from a friend that her father passed away last year. In the stuff was a home made weak link. I tossed it away, but it was a length of poly with clear plastic tubing over it and fishing line weaved through it several times. I guess the fishing line test was known and the number of weaves made the strength of the weak link. I'm sure he had tested the break strength of them before using. And I'm sure he made those way before anything commercial was available. Anyone ever seen or heard of a weak link like that?

The whiffle ball is free to slide on the tow rope. It slides up against the nose of the glider, including the release and pitot tube, but does not affect the airspeed indication.

We use hollow braid rope. For most of the gliders, 1/4 inch is strong enough. A stronger rope is used for the big, heavy gliders. The short piece, serving as the weak link, on both ends of the entire tow rope is only 3 feet or so long, and loops back, then weaves in and out three or four times, ending up inside the hollow braid rope.

The resulting loop is fed through the larger of the double Tost rings we use, then the free end of the weak/link tow rope (without the loop) goes through the loop in the rope before weaving in and out of the 1/4 inch rope serving as the weak link.

The other end of this weak link is fished inside of the actual, much stronger tow rope. We make it come in and out 3 or 4 times to keep it secure so it does not slip. No knots are used.

Of course both ends of the tow rope are assembled in the same manner, but the tow plane end does not have the whiffle ball.

The weak link / tow ring on the glider end of the tow rope is subject to the most abuse, and is carefully inspected by the wing runner, and pilot before each launch.

Most landings of the towplane at Ridge Soaring Gliderport are on grass. If we landed on a hard surface runway, we would have to re-think this. As a minimum, it might be necessary for the towplane to drop the rope.

Tom

On Wednesday, April 6, 2016 at 5:44:11 PM UTC+3, wrote:
The whiffle ball is free to slide on the tow rope. It slides up against the nose of the glider, including the release and pitot tube, but does not affect the airspeed indication.

We use hollow braid rope. For most of the gliders, 1/4 inch is strong enough. A stronger rope is used for the big, heavy gliders. The short piece, serving as the weak link, on both ends of the entire tow rope is only 3 feet or so long, and loops back, then weaves in and out three or four times, ending up inside the hollow braid rope.

The resulting loop is fed through the larger of the double Tost rings we use, then the free end of the weak/link tow rope (without the loop) goes through the loop in the rope before weaving in and out of the 1/4 inch rope serving as the weak link.

The other end of this weak link is fished inside of the actual, much stronger tow rope. We make it come in and out 3 or 4 times to keep it secure so it does not slip. No knots are used.

Of course both ends of the tow rope are assembled in the same manner, but the tow plane end does not have the whiffle ball.

The weak link / tow ring on the glider end of the tow rope is subject to the most abuse, and is carefully inspected by the wing runner, and pilot before each launch.

Most landings of the towplane at Ridge Soaring Gliderport are on grass. If we landed on a hard surface runway, we would have to re-think this. As a minimum, it might be necessary for the towplane to drop the rope.

How does the pilot carefully inspect the rope, given that they should be strapped in checks done before the towplane arrives?

We have the wing runner quickly inspect the last third or quarter or whatever of the rope while bringing it in front of the glider, and hold up the last arms-span of it to show the pilot there are no knots in at least that part, but the pilot is several meters away and isn't going to be inspecting the rings of detailed condition of the rope.