Jana’s absolutely right about there being thermals on both approaches. There’s just more loose dust on the parking lot side because cars are driving over it. When I was actively grading the undershoot of the HG side of the LZ, we had some really magnificent dust devils going right up the training hill.
I also agree with Jerome that airspeed has nothing to do with the approach type of DBF or figure-8.
It has a *lot* to do with why we separate the patterns, though. Relatively speaking, PGs are slow, HGs are fast. We try to keep them separate so HGs don’t overtake PGs, and PGs don’t block HGs.
The other reason for flying an approach pattern is so that people will know your intentions. An approach is not just flying around randomly until it looks like you’ll impact close to the spot you desire. We’re a busy site. Other people need to be able to predict where you’re going to go, and have a safe alternative.
My glider is fluoro red, white, fluoro orange. It’s bright, and doesn’t blend in very well. The last three PGs that have cut me off in the HG approach all said the same thing: “I didn’t see you.” All three episodes had me losing my altitude off the southeast corner of the LZ before attempting a DBF approach. I have to assume either they’re not looking, or they don’t recognize the fact that I’m in the pattern. Which may be why I find it particularly annoying, because I do follow a pattern.
One thing I don’t understand is why so many people want to lose altitude downwind of the LZ. That’s just silly. I see PGs dragging in low from the east all the freaking time. Why?
Is there some reason not to stay over the lift-generating hill and conserve altitude until upwind/crosswind from the LZ?
Here’s my recommendations:
Blow off your excess altitude crosswind or upwind of the LZ, so you don’t run the risk of not being able to penetrate to the LZ. Get your initial point altitude for a DBF approach approximately right, fly that making corrections as needed. If you’re still too high, sure, a couple of figure-8s may be necessary, but you should be trying to minimize the time you spend in the low approach area.