Saturday, September 29, 2012

How can there be lift EVERYWHERE?

I haven't posted for a while, though I have flown. Things have been pretty busy... I'll catch up on some recent events in the next post (I hope).

Today's forecast looked good, but with one caveat: NWS listed "broken cirrus" starting about 2:00 pm. "Broken" is a technical term that means more than half the sky. If that much cirrus came in, it could shut down ground heating. The soaring forecast showed a convergence of winds right across the top of the San Gabriel mountains - that would be good! Driving up from the south about 9:30, I could already see clouds right on the top, and it was way to early for them to be CU from thermal heating. The local instructor I usually check with said they had had great conditions for the last two weeks, and expected more of the same today.

I prepped the Grob 103. The gliderport was hosting a bunch of Boy Scouts flights... between those, a down towplane, a wind shift which meant towing six gliders to the west end of the runway, and a line mixup, I didn't launch until 1:45. Fortunately the cirrus was staying scattered. The lower clouds looked great - more over the mountains than the desert, and cycling fast enough you could tell new ones (good lift) from old ones.

On tow, we had an "event" - I don't know if you'd call it a close call or not. After takeoff we did a 270-degree turn to head south. That took us over the downwind leg for the opposite-direction runway. Fairly abruptly, the towplane climbed, not the typical flying-through-lift jump - and I had to catch up. Looking down, I saw a glider on downwind leg about 100-200 feet below us. I don't know if it caught the tow pilot by surprise and this was "evasive action" or whether he had him well in sight... but it was closer than I've ever come to another glider while on tow.

I let off at 2700' AGL (6100' MSL) in good lift. I found good stuff right away, and took successive thermals up to 8,000, 9,500, and then 10,600 over the mountains. I overflew Mt. Baden-Powell, then went chasing ever higher clouds.
Some like the ones above looked nice and sharp on top, which indicated they were growing and would have lift underneath. But they were cycling so fast that they died before I got to them.

In the next pic you can see I'm close up under some smaller ones. The trick was to look for wisps of moisture that were just starting to condense, and quickly get under them.

The highest I could get was about 11,000 MSL under these clouds. I very rarely hit any serious sink between patches of lift. Eventually I headed out over the desert and... the lift got even better. Away from the mountains, with their moist lift, it was all blue, but there were long straight stretches that I assume were convergence lift. I went probably ten miles straight north and was usually in zero sink or minor lift. Eventually I reached some little lakes and I was still at 10,000+. Then... I hit even MORE thermal lift (with no cloud to mark it) and worked that up to 12,500! This was probably the first time I've found a higher lift ceiling over the desert than over the mountains. It really felt like the lift was EVERYWHERE today. That's not usually possible - what goes up must come down - but if there was a large-scale convergence due to the south wind coming over the mountains, colliding with the mild offshore wind that was building, maybe there was a widespread general uplift in addition to the great thermals.

I decided to come in after about two hours of great flying, and had to use spoilers to get down from 10,000 feet! As I got down near our "report-in" altitude of 5000' MSL, I could see there was a glider staging for takeoff, and a glider on the radio was getting ready to land. Now usually, we have limited ability to go into a "holding pattern", but as I circled just to the west of the airport, I found a wide, gentle thermal. I held there for 10-15 minutes while one glider took off and three landed - and I had gained 1,500' without even trying. Highly unusual!

I ended up with a total flight time of 2 hours and 25 minutes. Everyone I talked to on the ground agreed it was a terrific day for lift.