Flyfunston

Dave Wills asked me to post this malfunction report that happened to his Laminar, but it might happen to other gliders as well.
Steve

>>>>>>>>>>>>>>>
I know there are quite a few Laminar pilots at Funston, so I wanted to post this here.

I've never seen or heard of this before, but yesterday my VG locked up in flight. During setup, I always pull on a little VG for launch. But I couldn't pull the line more than a few inches.
I checked inside my sail and the small, white (kevlar?) line that attaches to the nose cone had wrapped once around the front-most VG pulley. I unwrapped it and everything seemed fine.

After launching, I pulled and released my VG a couple of times. It seemed a little stiff, but not worrisome. Then, I went to release and it was jammed. After landing, I looked inside the sail and saw nothing out of the ordinary. But when I looked at the rear of the sail where the rear VG pulley is, I immediately saw the problem. The front pulley had twisted around itself a couple of times. This caused the six lines that go between the front and rear pulleys to twist up and prevent them from sliding between the pulleys.

It wasn't immediately obvious why this happened. I then pulled on the right-most line (looking forward from the rear of the keel) and pulled the line from the front. As I pulled that one line, it completely twisted up all by itself. The line looked as if you took the end between your thumb and forefinger and just spun it, twisting it many, many times.
Imagine how your telephone cord looks after many uses.

The twist in the line had eventually worked its way from the jam cleat end all the way to the 6 lines between the pulleys, and the overall affect on the 6 lines was to cause them to twist as a single line. Since the rear pulley is captured and the front pulley is not, the front pulley spun around itself and effectively locked the 6 lines together, preventing VG from working.

It took several iterations of untwisting the single line between the pulleys and working the twist out all the way up to the bottom of the down tube. When I was done though, VG worked fine again.

This is certainly something I'll have to look for periodically.

Also, I'm not very happy with the lock pin on the cross bar tension strap. The pin barely comes out of the keel far enough to lock the plate in the haul-back system, and sometimes it doesn't pop out of the keel far enough to effectively lock. Even when it is out all the way, I'm not convinced that the plate can't push the pin out of the way in very strong turbulence.

Dave