Sunday, May 30, 2010

Tehachapi Day 2 - Skunked Twice

My plan for today was to try for a very long local flight in the PW5, if weather conditions were favorable. I need a 5 hour flight to complete my Silver badge, and this was the first opprtunity where the glider availability, my preparation, and the weather might all come together. It looked possible according to the forecasts and models, with decent lift as high as 10,000' in the Tehachapi area (but not very far north), and light winds from the east: up to 15 knots on the ground, but only about 5 aloft. I planned to stay local if possible - I didn't see any reason to complicate the goal by going cross-country.

For a long flight like that, I made sure to take plenty of water, some snacks, fully charged battery, and a full oxygen tank. I planned to take off by about 11:30. A few other gliders launced before me, but no one had yet stayed up very long. I took off to the west (runway 27) at 11:15. I thought the tow pilot would take me over the mountains, but instead he took me over the valley upwind of the airport. The vario was all over the place - way up and way down. We encountered some lift, and I let off at 3100' AGL. I did a tight circle to "notch" the flight trace and to work the lift. Nothing but sink everywhere I went. I couldn't get up over the mountains so I tried to explore the valley. The sink was anywhere from 6 to 10 knots. Very soon I was forced to land, I think after 13 minutes.

I pushed the glider aside to think about the conditions and see if anyone else was staying up. Soon there was a line of about 8 waiting to launch. I was advised to try to get away from the valley and head north, that by this time of day often the thermals die off. This time I asked to go over the mountains, as I felt the chances were better there because I could see a couple of gliders. I took off to the east at 12:25. At 3000' AGL there was nothing. I held out until 3800' and let off in some lift. Again, I could not get back into the lift. I tried the bald spot - nothing. I tried the ridges, looking for anabatic lift (unlikely) or orographic (more likely). Sink over the foothills. Sink over the valley. At 2000' AGL I found one weak little thermal that I worked for quite a while but it only gave me 100'. This flight only lasted 27 minutes.

Another pilot took off in the PW5 at 2:07 and stayed up for two hours and reached 11,700' MSL. And some guys went up at 2:00 in the Grob and got 90 minutes. So I guess I was just unlucky.

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