Launching from Planfait again, an inversion capped our climbs to 4,500 ft. Without the required 6,000 ft. over Dents de Lanfon , we weren't going anywhere. Mad Dog, Don and I had extended flights (3+00) working two thermals that produced consistent, reliable lift; over launch and over the medieval castle of Menthon-St.Bernard. It was an excellent opportunity to refine thermalling skills.
Three hours in two thermals gives you quite a bit of time to discover things you wouldn't normally pick up on while flying XC. I reminded myself that the upwind portion is the strongest portion of the rising air mass. It also has a friendlier transition into and out of the lift. It's almost feathery where the downwind side tends to give you a bump-and-drop as you leave it, which gets more prominent with more strength.
The light wind gave the thermals a nice drift that forced us to focus on centering over a moving air mass, as opposed to a ground reference. But the drift wasn't always as consistent as one might imagine. They actually meandered, and I know this because a little bird told me.
While flying in the upwind portion of the castle thermal, I spotted a flock of loosely organized sparrows above me. I imagined that these where the same birds that fly their aerobatic maneuvers over the grassy fields at sunset behind Mad Dog & Jeannine's hamlet. I've shared thermals with them over Rabbit Is. on Oahu as well. I suspect they were feeding; in pursuit of insects pushed upward in the lifting air. Or maybe they were just trying to climb up to the rocky cliff face of the Dents, like us. Either way, they were with me in this thermal, and they were showing me things. These little guys are extremely maneuverable, but don't appear to have much of a glide ratio. Their glide is so poor, I was able to match them with mine! I picked one out above me and followed him. Instead of looking down as I normally do, I was looking up. It was different. I could see every move of my wing and with it, I think I could see where the thermal was going. The sparrow made five or six turns with the same radius as I think I would have if he weren't there. I held him close, just in front of my inside leading edge. Then, I saw him twitch a little left, a little right and he went straight for five or six seconds in a direction I didn't expect. I followed and the beeps continued. Then he entered another turn, this time in the other direction. I followed, free to do as I pleased with no other gliders near me. Steady beeps all the way up to 5,000 ft. I'm not sure I could follow a thermal that way without a guide bird, but I might try looking up more instead of staring down, as I'm prone to do. And in doing so, I may find another one of my new favorite thermal buddies.
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