Shear line soaring

The NWS forecast called for winds gusting to 45 MPH so we thought we'd get shut down, but they never came. Just the usual moderate west winds, which actually can make for decent soaring in the valley. The wind enters the Tehachapi valley from the west around two sides of a mountain, and the colliding winds set up a convergence, commonly called a "shear line". I've tried to work it before but never had much luck.

Today another pilot wanted to fly dual with me in the Grob 103. We don't have an instructor this trip, so the newer pilots pair up with more experienced pilots and learn about flying this location, or get experience in the Grob, or whatever. T had had some flights in the Grob but is not signed off to fly it yet. He flew from the front and I from the back as PIC. Since I'm still working on becoming an instructor, it's good experience for both of us.

We released at 2800' AGL (7000 MSL) and fairly promptly found a thermal that took us up to nearly 8000 MSL. That seemed to be the top of the lift all day, both shear and thermal. We went back and forth and usually found narrow bands of lift along a northwest-southeast line. Often it was too narrow to circle in, so it was apparently mostly shear line. At times we could fly directly upwind and still gain altitude. That sounds like a really odd thing to be able to do without an engine, huh? But if the wind is coming at you and colliding with wind from another angle, it deflects upward and takes you up! Kind of magical.

We traded off flying from time to time. There were three or four other gliders in the area, and we all followed each other to the lifting areas. We saw a grass fire start and get put out a few minutes later, and observed how the wind carried the smoke different directions at different altitudes. Wind shear made visible!

We used soaring ravens to find lift, and we came within a hundred feet or so of a hawk, which quickly turned and dived away from us. It was brownish on top and black-and-white underneath, which in my bird book looks like a Rough-Legged Hawk. I'm still hoping to encounter an eagle in flight some time.

Eventually we got a bit tired and ran out of drinking water, so we came down after 2 hours and 8 minutes.