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Old April 16th 19, 05:27 AM posted to rec.aviation.soaring
Steve Koerner
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Default Jonker JS-3 in Sagebrush

I know the pilot well and have had a lot of discussion with him about this. It turns out that this was the pilot's maiden flight in the JS3 and it turns out that the pilot has a bit of a thick brain and hadn't had enough opportunity to sit in the airplane and get familiar with the controls before setting sail.

After 16 years flying the ASW-27, muscle memory was involved. On downwind, the dive brakes were used to adjust appropriate pattern altitude starting from a high pattern entry from overhead, then somewhere on downwind the brakes were lastly put away. But, apparently not put away properly. The JS3 has several detent stops for holding the dive brake open at partial positions whereas the ASW-27 has only one detent at the closed and locked position.

By the time the poor SOB got to the base turn position he realized he was a bit lower than he expected and attributed that to sink. Bringing the turn around, he concluded that he was still in some pretty nasty sink. His split second decision was to get the airplane down on the deck for the dual purpose of getting into ground effect and secondly to get under the sink (sink always has to end at ground level when the ground is itself level). The intention was to attack the perimeter fence fast so as to be able to pop over it then on to runway 30. Plan C would be to land before the fence in the sagebrush if there wasn't positively enough energy to get over the fence.

As you already know from the original poster, plan C, landing before the fence was selected. Not surprisingly, speeding up with partially deployed air brakes caused energy to bleed all the more surely and quickly.

At touchdown a ground loop ensued that partly happened on top of the dense 4 foot high brush.

There's now a little bit of fix-it to be done on this beautiful new glider; nothing big enough to involve insurance companies.

When things go wrong there's takeaways... For JS3 flying, one must put eyeballs on the divebrake lever and its detents. It's not just push forward and lock anymore. We've learned that the hard way.

The other takeaway relates to adequate familiarizing with a new type. What I've done in the past with new gliders is to take them home to my workshop and sit in them for hours just playing with the controls and the instruments to make sure that I was totally familiar before taking flight for the first time. That was impractical this time. The program letter specifically required first flight at Minden and we were especially time squeezed because there were two of us who'd traveled long distance to get to Minden to pick up gliders and we needed to share one set of probes between two gliders (my JS3 arrived without probes); I was nominated to go first being the borrower in this instance.

Of course, that's all just sort of excuses. None of that should really have been a problem. I was properly briefed on the dive brake detents by a knowledgeable instructor and signed off accordingly. That little difference in the dive brake control design, though, just wasn't sufficiently engrained in this pilot's brain quite yet.

It's unusual to accidentally land out on your maiden flight with a brand new airplane. I'm feeling like a dodo for doing so and sad to have hurt my new bird.

Another big thank you to Mike and Tim and to Jim Lee for helping with my retrieve in that nasty sage brush.

As a postscript, I'm not so sure that having detent stops for open dive brakes is really a good idea. I'll think about that some more. I may decide to remove the detents. I suspect that there are other variations of the problem that I just had. It would be especially embarrassing if something like this happened to me again.